Service
public abstract class Service
extends ContextWrapper
implements ComponentCallbacks2
Known Direct Subclasses
AbstractInputMethodService,
AccessibilityService,
CallScreeningService,
CameraPrewarmService,
CarrierMessagingService,
CarrierService,
ChooserTargetService,
ConditionProviderService,
ConnectionService,
CustomTabsService,
DreamService,
HostApduService,
HostNfcFService, and
21 others.
AbstractInputMethodService |
AbstractInputMethodService provides a abstract base class for input methods. |
AccessibilityService |
Accessibility services are intended to assist users with disabilities in using Android devices and apps. |
CallScreeningService |
This service can be implemented by the default dialer (see getDefaultDialerPackage() ) to allow or disallow incoming calls before they are shown to a user. |
CameraPrewarmService |
Extend this class to implement a camera prewarm service. |
CarrierMessagingService |
A service that receives calls from the system when new SMS and MMS are sent or received. |
CarrierService |
A service that exposes carrier-specific functionality to the system. |
ChooserTargetService |
A service that receives calls from the system when the user is asked to choose a target for an intent explicitly by another app. |
ConditionProviderService |
A service that provides conditions about boolean state. |
ConnectionService |
An abstract service that should be implemented by any apps which can make phone calls (VoIP or otherwise) and want those calls to be integrated into the built-in phone app. |
CustomTabsService |
Abstract service class for implementing Custom Tabs related functionality. |
DreamService |
Extend this class to implement a custom dream (available to the user as a "Daydream"). |
HostApduService |
HostApduService is a convenience Service class that can be extended to emulate an NFC card inside an Android service component. |
HostNfcFService |
HostNfcFService is a convenience Service class that can be extended to emulate an NFC-F card inside an Android service component. |
InCallService |
This service is implemented by any app that wishes to provide the user-interface for managing phone calls. |
IntentService |
IntentService is a base class for Service s that handle asynchronous requests (expressed as Intent s) on demand. |
JobService |
Entry point for the callback from the JobScheduler . |
MediaBrowserService |
Base class for media browse services. |
MediaBrowserServiceCompat |
Base class for media browse services. |
MediaRouteProviderService |
Base class for media route provider services. |
MidiDeviceService |
A service that implements a virtual MIDI device. |
NotificationCompatSideChannelService |
Abstract service to receive side channel notifications sent from NotificationManagerCompat . |
NotificationListenerService |
A service that receives calls from the system when new notifications are posted or removed, or their ranking changed. |
OffHostApduService |
OffHostApduService is a convenience Service class that can be extended to describe one or more NFC applications that are residing off-host, for example on an embedded secure element or a UICC. |
PrintService |
This is the base class for implementing print services. |
RecognitionService |
This class provides a base class for recognition service implementations. |
RemoteViewsService |
The service to be connected to for a remote adapter to request RemoteViews. |
SettingInjectorService |
Dynamically specifies the enabled status of a preference injected into the list of app settings displayed by the system settings app For use only by apps that are included in the system image, for preferences that affect multiple apps. |
SpellCheckerService |
SpellCheckerService provides an abstract base class for a spell checker. |
TextToSpeechService |
Abstract base class for TTS engine implementations. |
TileService |
A TileService provides the user a tile that can be added to Quick Settings. |
TvInputService |
The TvInputService class represents a TV input or source such as HDMI or built-in tuner which provides pass-through video or broadcast TV programs. |
VoiceInteractionService |
Top-level service of the current global voice interactor, which is providing support for hotwording, the back-end of a VoiceInteractor , etc. |
VoiceInteractionSessionService |
An active voice interaction session, initiated by a VoiceInteractionService . |
VpnService |
VpnService is a base class for applications to extend and build their own VPN solutions. |
VrListenerService |
A service that is bound from the system while running in virtual reality (VR) mode. |
WallpaperService |
A wallpaper service is responsible for showing a live wallpaper behind applications that would like to sit on top of it. |
|
Known Indirect Subclasses
InputMethodService |
InputMethodService provides a standard implementation of an InputMethod, which final implementations can derive from and customize. |
|
A Service is an application component representing either an application's desire to perform a longer-running operation while not interacting with the user or to supply functionality for other applications to use. Each service class must have a corresponding <service>
declaration in its package's AndroidManifest.xml
. Services can be started with Context.startService()
and Context.bindService()
.
Note that services, like other application objects, run in the main thread of their hosting process. This means that, if your service is going to do any CPU intensive (such as MP3 playback) or blocking (such as networking) operations, it should spawn its own thread in which to do that work. More information on this can be found in Processes and Threads. The IntentService
class is available as a standard implementation of Service that has its own thread where it schedules its work to be done.
Topics covered here:
- What is a Service?
- Service Lifecycle
- Permissions
- Process Lifecycle
- Local Service Sample
- Remote Messenger Service Sample
Developer Guides
For a detailed discussion about how to create services, read the Services developer guide.
What is a Service?
Most confusion about the Service class actually revolves around what it is not:
- A Service is not a separate process. The Service object itself does not imply it is running in its own process; unless otherwise specified, it runs in the same process as the application it is part of.
- A Service is not a thread. It is not a means itself to do work off of the main thread (to avoid Application Not Responding errors).
Thus a Service itself is actually very simple, providing two main features:
- A facility for the application to tell the system about something it wants to be doing in the background (even when the user is not directly interacting with the application). This corresponds to calls to
Context.startService()
, which ask the system to schedule work for the service, to be run until the service or someone else explicitly stop it.
- A facility for an application to expose some of its functionality to other applications. This corresponds to calls to
Context.bindService()
, which allows a long-standing connection to be made to the service in order to interact with it.
When a Service component is actually created, for either of these reasons, all that the system actually does is instantiate the component and call its onCreate()
and any other appropriate callbacks on the main thread. It is up to the Service to implement these with the appropriate behavior, such as creating a secondary thread in which it does its work.
Note that because Service itself is so simple, you can make your interaction with it as simple or complicated as you want: from treating it as a local Java object that you make direct method calls on (as illustrated by Local Service Sample), to providing a full remoteable interface using AIDL.
Service Lifecycle
There are two reasons that a service can be run by the system. If someone calls Context.startService()
then the system will retrieve the service (creating it and calling its onCreate()
method if needed) and then call its onStartCommand(Intent, int, int)
method with the arguments supplied by the client. The service will at this point continue running until Context.stopService()
or stopSelf()
is called. Note that multiple calls to Context.startService() do not nest (though they do result in multiple corresponding calls to onStartCommand()), so no matter how many times it is started a service will be stopped once Context.stopService() or stopSelf() is called; however, services can use their stopSelf(int)
method to ensure the service is not stopped until started intents have been processed.
For started services, there are two additional major modes of operation they can decide to run in, depending on the value they return from onStartCommand(): START_STICKY
is used for services that are explicitly started and stopped as needed, while START_NOT_STICKY
or START_REDELIVER_INTENT
are used for services that should only remain running while processing any commands sent to them. See the linked documentation for more detail on the semantics.
Clients can also use Context.bindService()
to obtain a persistent connection to a service. This likewise creates the service if it is not already running (calling onCreate()
while doing so), but does not call onStartCommand(). The client will receive the IBinder
object that the service returns from its onBind(Intent)
method, allowing the client to then make calls back to the service. The service will remain running as long as the connection is established (whether or not the client retains a reference on the service's IBinder). Usually the IBinder returned is for a complex interface that has been written in aidl.
A service can be both started and have connections bound to it. In such a case, the system will keep the service running as long as either it is started or there are one or more connections to it with the Context.BIND_AUTO_CREATE
flag. Once neither of these situations hold, the service's onDestroy()
method is called and the service is effectively terminated. All cleanup (stopping threads, unregistering receivers) should be complete upon returning from onDestroy().
Permissions
Global access to a service can be enforced when it is declared in its manifest's <service>
tag. By doing so, other applications will need to declare a corresponding <uses-permission>
element in their own manifest to be able to start, stop, or bind to the service.
As of GINGERBREAD
, when using Context.startService(Intent)
, you can also set Intent.FLAG_GRANT_READ_URI_PERMISSION
and/or Intent.FLAG_GRANT_WRITE_URI_PERMISSION
on the Intent. This will grant the Service temporary access to the specific URIs in the Intent. Access will remain until the Service has called stopSelf(int)
for that start command or a later one, or until the Service has been completely stopped. This works for granting access to the other apps that have not requested the permission protecting the Service, or even when the Service is not exported at all.
In addition, a service can protect individual IPC calls into it with permissions, by calling the checkCallingPermission(String)
method before executing the implementation of that call.
See the Security and Permissions document for more information on permissions and security in general.
Process Lifecycle
The Android system will attempt to keep the process hosting a service around as long as the service has been started or has clients bound to it. When running low on memory and needing to kill existing processes, the priority of a process hosting the service will be the higher of the following possibilities:
If the service is currently executing code in its onCreate()
, onStartCommand()
, or onDestroy()
methods, then the hosting process will be a foreground process to ensure this code can execute without being killed.
If the service has been started, then its hosting process is considered to be less important than any processes that are currently visible to the user on-screen, but more important than any process not visible. Because only a few processes are generally visible to the user, this means that the service should not be killed except in low memory conditions. However, since the user is not directly aware of a background service, in that state it is considered a valid candidate to kill, and you should be prepared for this to happen. In particular, long-running services will be increasingly likely to kill and are guaranteed to be killed (and restarted if appropriate) if they remain started long enough.
If there are clients bound to the service, then the service's hosting process is never less important than the most important client. That is, if one of its clients is visible to the user, then the service itself is considered to be visible. The way a client's importance impacts the service's importance can be adjusted through BIND_ABOVE_CLIENT
, BIND_ALLOW_OOM_MANAGEMENT
, BIND_WAIVE_PRIORITY
, BIND_IMPORTANT
, and BIND_ADJUST_WITH_ACTIVITY
.
A started service can use the startForeground(int, Notification)
API to put the service in a foreground state, where the system considers it to be something the user is actively aware of and thus not a candidate for killing when low on memory. (It is still theoretically possible for the service to be killed under extreme memory pressure from the current foreground application, but in practice this should not be a concern.)
Note this means that most of the time your service is running, it may be killed by the system if it is under heavy memory pressure. If this happens, the system will later try to restart the service. An important consequence of this is that if you implement onStartCommand()
to schedule work to be done asynchronously or in another thread, then you may want to use START_FLAG_REDELIVERY
to have the system re-deliver an Intent for you so that it does not get lost if your service is killed while processing it.
Other application components running in the same process as the service (such as an Activity
) can, of course, increase the importance of the overall process beyond just the importance of the service itself.
Local Service Sample
One of the most common uses of a Service is as a secondary component running alongside other parts of an application, in the same process as the rest of the components. All components of an .apk run in the same process unless explicitly stated otherwise, so this is a typical situation.
When used in this way, by assuming the components are in the same process, you can greatly simplify the interaction between them: clients of the service can simply cast the IBinder they receive from it to a concrete class published by the service.
An example of this use of a Service is shown here. First is the Service itself, publishing a custom class when bound:
public class LocalService extends Service {
private NotificationManager mNM;
// Unique Identification Number for the Notification.
// We use it on Notification start, and to cancel it.
private int NOTIFICATION = R.string.local_service_started;
/**
* Class for clients to access. Because we know this service always
* runs in the same process as its clients, we don't need to deal with
* IPC.
*/
public class LocalBinder extends Binder {
LocalService getService() {
return LocalService.this;
}
}
@Override
public void onCreate() {
mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
// Display a notification about us starting. We put an icon in the status bar.
showNotification();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i("LocalService", "Received start id " + startId + ": " + intent);
return START_NOT_STICKY;
}
@Override
public void onDestroy() {
// Cancel the persistent notification.
mNM.cancel(NOTIFICATION);
// Tell the user we stopped.
Toast.makeText(this, R.string.local_service_stopped, Toast.LENGTH_SHORT).show();
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
// This is the object that receives interactions from clients. See
// RemoteService for a more complete example.
private final IBinder mBinder = new LocalBinder();
/**
* Show a notification while this service is running.
*/
private void showNotification() {
// In this sample, we'll use the same text for the ticker and the expanded notification
CharSequence text = getText(R.string.local_service_started);
// The PendingIntent to launch our activity if the user selects this notification
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
new Intent(this, LocalServiceActivities.Controller.class), 0);
// Set the info for the views that show in the notification panel.
Notification notification = new Notification.Builder(this)
.setSmallIcon(R.drawable.stat_sample) // the status icon
.setTicker(text) // the status text
.setWhen(System.currentTimeMillis()) // the time stamp
.setContentTitle(getText(R.string.local_service_label)) // the label of the entry
.setContentText(text) // the contents of the entry
.setContentIntent(contentIntent) // The intent to send when the entry is clicked
.build();
// Send the notification.
mNM.notify(NOTIFICATION, notification);
}
}
With that done, one can now write client code that directly accesses the running service, such as:
private LocalService mBoundService;
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
// This is called when the connection with the service has been
// established, giving us the service object we can use to
// interact with the service. Because we have bound to a explicit
// service that we know is running in our own process, we can
// cast its IBinder to a concrete class and directly access it.
mBoundService = ((LocalService.LocalBinder)service).getService();
// Tell the user about this for our demo.
Toast.makeText(Binding.this, R.string.local_service_connected,
Toast.LENGTH_SHORT).show();
}
public void onServiceDisconnected(ComponentName className) {
// This is called when the connection with the service has been
// unexpectedly disconnected -- that is, its process crashed.
// Because it is running in our same process, we should never
// see this happen.
mBoundService = null;
Toast.makeText(Binding.this, R.string.local_service_disconnected,
Toast.LENGTH_SHORT).show();
}
};
void doBindService() {
// Establish a connection with the service. We use an explicit
// class name because we want a specific service implementation that
// we know will be running in our own process (and thus won't be
// supporting component replacement by other applications).
bindService(new Intent(Binding.this,
LocalService.class), mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
}
void doUnbindService() {
if (mIsBound) {
// Detach our existing connection.
unbindService(mConnection);
mIsBound = false;
}
}
@Override
protected void onDestroy() {
super.onDestroy();
doUnbindService();
}
Remote Messenger Service Sample
If you need to be able to write a Service that can perform complicated communication with clients in remote processes (beyond simply the use of Context.startService
to send commands to it), then you can use the Messenger
class instead of writing full AIDL files.
An example of a Service that uses Messenger as its client interface is shown here. First is the Service itself, publishing a Messenger to an internal Handler when bound:
public class MessengerService extends Service {
/** For showing and hiding our notification. */
NotificationManager mNM;
/** Keeps track of all current registered clients. */
ArrayList<Messenger> mClients = new ArrayList<Messenger>();
/** Holds last value set by a client. */
int mValue = 0;
/**
* Command to the service to register a client, receiving callbacks
* from the service. The Message's replyTo field must be a Messenger of
* the client where callbacks should be sent.
*/
static final int MSG_REGISTER_CLIENT = 1;
/**
* Command to the service to unregister a client, ot stop receiving callbacks
* from the service. The Message's replyTo field must be a Messenger of
* the client as previously given with MSG_REGISTER_CLIENT.
*/
static final int MSG_UNREGISTER_CLIENT = 2;
/**
* Command to service to set a new value. This can be sent to the
* service to supply a new value, and will be sent by the service to
* any registered clients with the new value.
*/
static final int MSG_SET_VALUE = 3;
/**
* Handler of incoming messages from clients.
*/
class IncomingHandler extends Handler {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_REGISTER_CLIENT:
mClients.add(msg.replyTo);
break;
case MSG_UNREGISTER_CLIENT:
mClients.remove(msg.replyTo);
break;
case MSG_SET_VALUE:
mValue = msg.arg1;
for (int i=mClients.size()-1; i>=0; i--) {
try {
mClients.get(i).send(Message.obtain(null,
MSG_SET_VALUE, mValue, 0));
} catch (RemoteException e) {
// The client is dead. Remove it from the list;
// we are going through the list from back to front
// so this is safe to do inside the loop.
mClients.remove(i);
}
}
break;
default:
super.handleMessage(msg);
}
}
}
/**
* Target we publish for clients to send messages to IncomingHandler.
*/
final Messenger mMessenger = new Messenger(new IncomingHandler());
@Override
public void onCreate() {
mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
// Display a notification about us starting.
showNotification();
}
@Override
public void onDestroy() {
// Cancel the persistent notification.
mNM.cancel(R.string.remote_service_started);
// Tell the user we stopped.
Toast.makeText(this, R.string.remote_service_stopped, Toast.LENGTH_SHORT).show();
}
/**
* When binding to the service, we return an interface to our messenger
* for sending messages to the service.
*/
@Override
public IBinder onBind(Intent intent) {
return mMessenger.getBinder();
}
/**
* Show a notification while this service is running.
*/
private void showNotification() {
// In this sample, we'll use the same text for the ticker and the expanded notification
CharSequence text = getText(R.string.remote_service_started);
// The PendingIntent to launch our activity if the user selects this notification
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
new Intent(this, Controller.class), 0);
// Set the info for the views that show in the notification panel.
Notification notification = new Notification.Builder(this)
.setSmallIcon(R.drawable.stat_sample) // the status icon
.setTicker(text) // the status text
.setWhen(System.currentTimeMillis()) // the time stamp
.setContentTitle(getText(R.string.local_service_label)) // the label of the entry
.setContentText(text) // the contents of the entry
.setContentIntent(contentIntent) // The intent to send when the entry is clicked
.build();
// Send the notification.
// We use a string id because it is a unique number. We use it later to cancel.
mNM.notify(R.string.remote_service_started, notification);
}
}
If we want to make this service run in a remote process (instead of the standard one for its .apk), we can use android:process
in its manifest tag to specify one:
<service android:name=".app.MessengerService"
android:process=":remote" />
Note that the name "remote" chosen here is arbitrary, and you can use other names if you want additional processes. The ':' prefix appends the name to your package's standard process name.
With that done, clients can now bind to the service and send messages to it. Note that this allows clients to register with it to receive messages back as well:
/** Messenger for communicating with service. */
Messenger mService = null;
/** Flag indicating whether we have called bind on the service. */
boolean mIsBound;
/** Some text view we are using to show state information. */
TextView mCallbackText;
/**
* Handler of incoming messages from service.
*/
class IncomingHandler extends Handler {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MessengerService.MSG_SET_VALUE:
mCallbackText.setText("Received from service: " + msg.arg1);
break;
default:
super.handleMessage(msg);
}
}
}
/**
* Target we publish for clients to send messages to IncomingHandler.
*/
final Messenger mMessenger = new Messenger(new IncomingHandler());
/**
* Class for interacting with the main interface of the service.
*/
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className,
IBinder service) {
// This is called when the connection with the service has been
// established, giving us the service object we can use to
// interact with the service. We are communicating with our
// service through an IDL interface, so get a client-side
// representation of that from the raw service object.
mService = new Messenger(service);
mCallbackText.setText("Attached.");
// We want to monitor the service for as long as we are
// connected to it.
try {
Message msg = Message.obtain(null,
MessengerService.MSG_REGISTER_CLIENT);
msg.replyTo = mMessenger;
mService.send(msg);
// Give it some value as an example.
msg = Message.obtain(null,
MessengerService.MSG_SET_VALUE, this.hashCode(), 0);
mService.send(msg);
} catch (RemoteException e) {
// In this case the service has crashed before we could even
// do anything with it; we can count on soon being
// disconnected (and then reconnected if it can be restarted)
// so there is no need to do anything here.
}
// As part of the sample, tell the user what happened.
Toast.makeText(Binding.this, R.string.remote_service_connected,
Toast.LENGTH_SHORT).show();
}
public void onServiceDisconnected(ComponentName className) {
// This is called when the connection with the service has been
// unexpectedly disconnected -- that is, its process crashed.
mService = null;
mCallbackText.setText("Disconnected.");
// As part of the sample, tell the user what happened.
Toast.makeText(Binding.this, R.string.remote_service_disconnected,
Toast.LENGTH_SHORT).show();
}
};
void doBindService() {
// Establish a connection with the service. We use an explicit
// class name because there is no reason to be able to let other
// applications replace our component.
bindService(new Intent(Binding.this,
MessengerService.class), mConnection, Context.BIND_AUTO_CREATE);
mIsBound = true;
mCallbackText.setText("Binding.");
}
void doUnbindService() {
if (mIsBound) {
// If we have received the service, and hence registered with
// it, then now is the time to unregister.
if (mService != null) {
try {
Message msg = Message.obtain(null,
MessengerService.MSG_UNREGISTER_CLIENT);
msg.replyTo = mMessenger;
mService.send(msg);
} catch (RemoteException e) {
// There is nothing special we need to do if the service
// has crashed.
}
}
// Detach our existing connection.
unbindService(mConnection);
mIsBound = false;
mCallbackText.setText("Unbinding.");
}
}
Summary
Constants |
int |
START_CONTINUATION_MASK Bits returned by onStartCommand(Intent, int, int) describing how to continue the service if it is killed. |
int |
START_FLAG_REDELIVERY This flag is set in onStartCommand(Intent, int, int) if the Intent is a re-delivery of a previously delivered intent, because the service had previously returned START_REDELIVER_INTENT but had been killed before calling stopSelf(int) for that Intent. |
int |
START_FLAG_RETRY This flag is set in onStartCommand(Intent, int, int) if the Intent is a retry because the original attempt never got to or returned from onStartCommand(Intent, int, int) . |
int |
START_NOT_STICKY Constant to return from onStartCommand(Intent, int, int) : if this service's process is killed while it is started (after returning from onStartCommand(Intent, int, int) ), and there are no new start intents to deliver to it, then take the service out of the started state and don't recreate until a future explicit call to Context.startService(Intent) . |
int |
START_REDELIVER_INTENT Constant to return from onStartCommand(Intent, int, int) : if this service's process is killed while it is started (after returning from onStartCommand(Intent, int, int) ), then it will be scheduled for a restart and the last delivered Intent re-delivered to it again via onStartCommand(Intent, int, int) . |
int |
START_STICKY Constant to return from onStartCommand(Intent, int, int) : if this service's process is killed while it is started (after returning from onStartCommand(Intent, int, int) ), then leave it in the started state but don't retain this delivered intent. |
int |
START_STICKY_COMPATIBILITY Constant to return from onStartCommand(Intent, int, int) : compatibility version of START_STICKY that does not guarantee that onStartCommand(Intent, int, int) will be called again after being killed. |
int |
STOP_FOREGROUND_DETACH Flag for stopForeground(int) : if set, the notification previously provided to startForeground(int, Notification) will be detached from the service. |
int |
STOP_FOREGROUND_REMOVE Flag for stopForeground(int) : if set, the notification previously provided to startForeground(int, Notification) will be removed. |
Inherited constants |
From class android.content.Context
String |
ACCESSIBILITY_SERVICE Use with getSystemService(Class
)
to retrieve a AccessibilityManager for giving the user feedback for UI events through the registered event listeners. |
String |
ACCOUNT_SERVICE Use with getSystemService(Class
)
to retrieve a AccountManager for receiving intents at a time of your choosing. |
String |
ACTIVITY_SERVICE Use with getSystemService(Class
)
to retrieve a ActivityManager for interacting with the global system state. |
String |
ALARM_SERVICE Use with getSystemService(Class
)
to retrieve a AlarmManager for receiving intents at a time of your choosing. |
String |
APPWIDGET_SERVICE Use with getSystemService(Class
)
to retrieve a AppWidgetManager for accessing AppWidgets. |
String |
APP_OPS_SERVICE Use with getSystemService(Class
)
to retrieve a AppOpsManager for tracking application operations on the device. |
String |
AUDIO_SERVICE Use with getSystemService(Class
)
to retrieve a AudioManager for handling management of volume, ringer modes and audio routing. |
String |
BATTERY_SERVICE Use with getSystemService(Class
)
to retrieve a BatteryManager for managing battery state. |
int |
BIND_ABOVE_CLIENT Flag for bindService(Intent, ServiceConnection, int) : indicates that the client application binding to this service considers the service to be more important than the app itself. |
int |
BIND_ADJUST_WITH_ACTIVITY Flag for bindService(Intent, ServiceConnection, int) : If binding from an activity, allow the target service's process importance to be raised based on whether the activity is visible to the user, regardless whether another flag is used to reduce the amount that the client process's overall importance is used to impact it. |
int |
BIND_ALLOW_OOM_MANAGEMENT Flag for bindService(Intent, ServiceConnection, int) : allow the process hosting the bound service to go through its normal memory management. |
int |
BIND_AUTO_CREATE Flag for bindService(Intent, ServiceConnection, int) : automatically create the service as long as the binding exists. |
int |
BIND_DEBUG_UNBIND Flag for bindService(Intent, ServiceConnection, int) : include debugging help for mismatched calls to unbind. |
int |
BIND_EXTERNAL_SERVICE Flag for bindService(Intent, ServiceConnection, int) : The service being bound is an isolated , external service. |
int |
BIND_IMPORTANT Flag for bindService(Intent, ServiceConnection, int) : this service is very important to the client, so should be brought to the foreground process level when the client is. |
int |
BIND_NOT_FOREGROUND Flag for bindService(Intent, ServiceConnection, int) : don't allow this binding to raise the target service's process to the foreground scheduling priority. |
int |
BIND_WAIVE_PRIORITY Flag for bindService(Intent, ServiceConnection, int) : don't impact the scheduling or memory management priority of the target service's hosting process. |
String |
BLUETOOTH_SERVICE Use with getSystemService(Class
)
to retrieve a BluetoothManager for using Bluetooth. |
String |
CAMERA_SERVICE Use with getSystemService(Class
)
to retrieve a CameraManager for interacting with camera devices. |
String |
CAPTIONING_SERVICE Use with getSystemService(Class
)
to retrieve a CaptioningManager for obtaining captioning properties and listening for changes in captioning preferences. |
String |
CARRIER_CONFIG_SERVICE Use with getSystemService(Class
)
to retrieve a CarrierConfigManager for reading carrier configuration values. |
String |
CLIPBOARD_SERVICE Use with getSystemService(Class
)
to retrieve a ClipboardManager for accessing and modifying ClipboardManager for accessing and modifying the contents of the global clipboard. |
String |
CONNECTIVITY_SERVICE Use with getSystemService(Class
)
to retrieve a ConnectivityManager for handling management of network connections. |
String |
CONSUMER_IR_SERVICE Use with getSystemService(Class
)
to retrieve a ConsumerIrManager for transmitting infrared signals from the device. |
int |
CONTEXT_IGNORE_SECURITY Flag for use with createPackageContext(String, int) : ignore any security restrictions on the Context being requested, allowing it to always be loaded. |
int |
CONTEXT_INCLUDE_CODE Flag for use with createPackageContext(String, int) : include the application code with the context. |
int |
CONTEXT_RESTRICTED Flag for use with createPackageContext(String, int) : a restricted context may disable specific features. |
String |
DEVICE_POLICY_SERVICE Use with getSystemService(Class
)
to retrieve a DevicePolicyManager for working with global device policy management. |
String |
DISPLAY_SERVICE Use with getSystemService(Class
)
to retrieve a DisplayManager for interacting with display devices. |
String |
DOWNLOAD_SERVICE Use with getSystemService(Class
)
to retrieve a DownloadManager for requesting HTTP downloads. |
String |
DROPBOX_SERVICE Use with getSystemService(Class
)
to retrieve a DropBoxManager instance for recording diagnostic logs. |
String |
FINGERPRINT_SERVICE Use with getSystemService(Class
)
to retrieve a FingerprintManager for handling management of fingerprints. |
String |
HARDWARE_PROPERTIES_SERVICE Use with getSystemService(Class
)
to retrieve a HardwarePropertiesManager for accessing the hardware properties service. |
String |
INPUT_METHOD_SERVICE Use with getSystemService(Class
)
to retrieve a InputMethodManager for accessing input methods. |
String |
INPUT_SERVICE Use with getSystemService(Class
)
to retrieve a InputManager for interacting with input devices. |
String |
JOB_SCHEDULER_SERVICE Use with getSystemService(Class
)
to retrieve a JobScheduler instance for managing occasional background tasks. |
String |
KEYGUARD_SERVICE Use with getSystemService(Class
)
to retrieve a NotificationManager for controlling keyguard. |
String |
LAUNCHER_APPS_SERVICE Use with getSystemService(Class
)
to retrieve a LauncherApps for querying and monitoring launchable apps across profiles of a user. |
String |
LAYOUT_INFLATER_SERVICE Use with getSystemService(Class
)
to retrieve a LayoutInflater for inflating layout resources in this context. |
String |
LOCATION_SERVICE Use with getSystemService(Class
)
to retrieve a LocationManager for controlling location updates. |
String |
MEDIA_PROJECTION_SERVICE Use with getSystemService(Class
)
to retrieve a MediaProjectionManager instance for managing media projection sessions. |
String |
MEDIA_ROUTER_SERVICE Use with getSystemService(Class
)
to retrieve a MediaRouter for controlling and managing routing of media. |
String |
MEDIA_SESSION_SERVICE Use with getSystemService(Class
)
to retrieve a MediaSessionManager for managing media Sessions. |
String |
MIDI_SERVICE Use with getSystemService(Class
)
to retrieve a MidiManager for accessing the MIDI service. |
int |
MODE_APPEND File creation mode: for use with openFileOutput(String, int) , if the file already exists then write data to the end of the existing file instead of erasing it. |
int |
MODE_ENABLE_WRITE_AHEAD_LOGGING Database open flag: when set, the database is opened with write-ahead logging enabled by default. |
int |
MODE_MULTI_PROCESS This constant was deprecated in API level 23. MODE_MULTI_PROCESS does not work reliably in some versions of Android, and furthermore does not provide any mechanism for reconciling concurrent modifications across processes. Applications should not attempt to use it. Instead, they should use an explicit cross-process data management approach such as ContentProvider . |
int |
MODE_NO_LOCALIZED_COLLATORS Database open flag: when set, the database is opened without support for localized collators. |
int |
MODE_PRIVATE File creation mode: the default mode, where the created file can only be accessed by the calling application (or all applications sharing the same user ID). |
int |
MODE_WORLD_READABLE This constant was deprecated in API level 17. Creating world-readable files is very dangerous, and likely to cause security holes in applications. It is strongly discouraged; instead, applications should use more formal mechanism for interactions such as ContentProvider , BroadcastReceiver , and Service . There are no guarantees that this access mode will remain on a file, such as when it goes through a backup and restore. |
int |
MODE_WORLD_WRITEABLE This constant was deprecated in API level 17. Creating world-writable files is very dangerous, and likely to cause security holes in applications. It is strongly discouraged; instead, applications should use more formal mechanism for interactions such as ContentProvider , BroadcastReceiver , and Service . There are no guarantees that this access mode will remain on a file, such as when it goes through a backup and restore. |
String |
NETWORK_STATS_SERVICE Use with getSystemService(Class
)
to retrieve a NetworkStatsManager for querying network usage stats. |
String |
NFC_SERVICE Use with getSystemService(Class
)
to retrieve a NfcManager for using NFC. |
String |
NOTIFICATION_SERVICE Use with getSystemService(Class
)
to retrieve a NotificationManager for informing the user of background events. |
String |
NSD_SERVICE Use with getSystemService(Class
)
to retrieve a NsdManager for handling management of network service discovery |
String |
POWER_SERVICE Use with getSystemService(Class
)
to retrieve a PowerManager for controlling power management, including "wake locks," which let you keep the device on while you're running long tasks. |
String |
PRINT_SERVICE PrintManager for printing and managing printers and print tasks. |
String |
RESTRICTIONS_SERVICE Use with getSystemService(Class
)
to retrieve a RestrictionsManager for retrieving application restrictions and requesting permissions for restricted operations. |
String |
SEARCH_SERVICE Use with getSystemService(Class
)
to retrieve a SearchManager for handling searches. |
String |
SENSOR_SERVICE Use with getSystemService(Class
)
to retrieve a SensorManager for accessing sensors. |
String |
STORAGE_SERVICE Use with getSystemService(Class
)
to retrieve a StorageManager for accessing system storage functions. |
String |
SYSTEM_HEALTH_SERVICE Use with getSystemService(Class
)
to retrieve a SystemHealthManager for accessing system health (battery, power, memory, etc) metrics. |
String |
TELECOM_SERVICE Use with getSystemService(Class
)
to retrieve a TelecomManager to manage telecom-related features of the device. |
String |
TELEPHONY_SERVICE Use with getSystemService(Class
)
to retrieve a TelephonyManager for handling management the telephony features of the device. |
String |
TELEPHONY_SUBSCRIPTION_SERVICE Use with getSystemService(Class
)
to retrieve a SubscriptionManager for handling management the telephony subscriptions of the device. |
String |
TEXT_SERVICES_MANAGER_SERVICE Use with getSystemService(Class
)
to retrieve a TextServicesManager for accessing text services. |
String |
TV_INPUT_SERVICE Use with getSystemService(Class
)
to retrieve a TvInputManager for interacting with TV inputs on the device. |
String |
UI_MODE_SERVICE Use with getSystemService(Class
)
to retrieve a UiModeManager for controlling UI modes. |
String |
USAGE_STATS_SERVICE Use with getSystemService(Class
)
to retrieve a UsageStatsManager for querying device usage stats. |
String |
USB_SERVICE Use with getSystemService(Class
)
to retrieve a UsbManager for access to USB devices (as a USB host) and for controlling this device's behavior as a USB device. |
String |
USER_SERVICE Use with getSystemService(Class
)
to retrieve a UserManager for managing users on devices that support multiple users. |
String |
VIBRATOR_SERVICE Use with getSystemService(Class
)
to retrieve a Vibrator for interacting with the vibration hardware. |
String |
WALLPAPER_SERVICE Use with getSystemService(Class
)
to retrieve a com.android.server.WallpaperService for accessing wallpapers. |
String |
WIFI_P2P_SERVICE Use with getSystemService(Class
)
to retrieve a WifiP2pManager for handling management of Wi-Fi peer-to-peer connections. |
String |
WIFI_SERVICE Use with getSystemService(Class
)
to retrieve a WifiManager for handling management of Wi-Fi access. |
String |
WINDOW_SERVICE Use with getSystemService(Class
)
to retrieve a WindowManager for accessing the system's window manager. |
|
From interface android.content.ComponentCallbacks2
|
Public methods |
final Application |
getApplication() Return the application that owns this service. |
abstract IBinder |
onBind(Intent intent) Return the communication channel to the service. |
void |
onConfigurationChanged(Configuration newConfig) Called by the system when the device configuration changes while your component is running. |
void |
onCreate() Called by the system when the service is first created. |
void |
onDestroy() Called by the system to notify a Service that it is no longer used and is being removed. |
void |
onLowMemory() This is called when the overall system is running low on memory, and actively running processes should trim their memory usage. |
void |
onRebind(Intent intent) Called when new clients have connected to the service, after it had previously been notified that all had disconnected in its onUnbind(Intent) . |
void |
onStart(Intent intent, int startId) This method was deprecated in API level 5. Implement onStartCommand(Intent, int, int) instead. |
int |
onStartCommand(Intent intent, int flags, int startId) Called by the system every time a client explicitly starts the service by calling startService(Intent) , providing the arguments it supplied and a unique integer token representing the start request. |
void |
onTaskRemoved(Intent rootIntent) This is called if the service is currently running and the user has removed a task that comes from the service's application. |
void |
onTrimMemory(int level) Called when the operating system has determined that it is a good time for a process to trim unneeded memory from its process. |
boolean |
onUnbind(Intent intent) Called when all clients have disconnected from a particular interface published by the service. |
final void |
startForeground(int id, Notification notification) Make this service run in the foreground, supplying the ongoing notification to be shown to the user while in this state. |
final void |
stopForeground(int flags) Remove this service from foreground state, allowing it to be killed if more memory is needed. |
final void |
stopForeground(boolean removeNotification) Synonym for stopForeground(int) . |
final void |
stopSelf() Stop the service, if it was previously started. |
final void |
stopSelf(int startId) Old version of stopSelfResult(int) that doesn't return a result. |
final boolean |
stopSelfResult(int startId) Stop the service if the most recent time it was started was startId. |
Inherited methods |
From class android.content.ContextWrapper
void |
attachBaseContext(Context base) Set the base context for this ContextWrapper. |
boolean |
bindService(Intent service, ServiceConnection conn, int flags) Connect to an application service, creating it if needed. |
int |
checkCallingOrSelfPermission(String permission) Determine whether the calling process of an IPC or you have been granted a particular permission. |
int |
checkCallingOrSelfUriPermission(Uri uri, int modeFlags) Determine whether the calling process of an IPC or you has been granted permission to access a specific URI. |
int |
checkCallingPermission(String permission) Determine whether the calling process of an IPC you are handling has been granted a particular permission. |
int |
checkCallingUriPermission(Uri uri, int modeFlags) Determine whether the calling process and user ID has been granted permission to access a specific URI. |
int |
checkPermission(String permission, int pid, int uid) Determine whether the given permission is allowed for a particular process and user ID running in the system. |
int |
checkSelfPermission(String permission) Determine whether you have been granted a particular permission. |
int |
checkUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags) Check both a Uri and normal permission. |
int |
checkUriPermission(Uri uri, int pid, int uid, int modeFlags) Determine whether a particular process and user ID has been granted permission to access a specific URI. |
void |
clearWallpaper() This method was deprecated in API level 23. Use WallpaperManager.clear() instead. This method requires the caller to hold the permission SET_WALLPAPER . |
Context |
createConfigurationContext(Configuration overrideConfiguration) Return a new Context object for the current Context but whose resources are adjusted to match the given Configuration. |
Context |
createDeviceProtectedStorageContext() Return a new Context object for the current Context but whose storage APIs are backed by device-protected storage. |
Context |
createDisplayContext(Display display) Return a new Context object for the current Context but whose resources are adjusted to match the metrics of the given Display. |
Context |
createPackageContext(String packageName, int flags) Return a new Context object for the given application name. |
String[] |
databaseList() Returns an array of strings naming the private databases associated with this Context's application package. |
boolean |
deleteDatabase(String name) Delete an existing private SQLiteDatabase associated with this Context's application package. |
boolean |
deleteFile(String name) Delete the given private file associated with this Context's application package. |
boolean |
deleteSharedPreferences(String name) Delete an existing shared preferences file. |
void |
enforceCallingOrSelfPermission(String permission, String message) If neither you nor the calling process of an IPC you are handling has been granted a particular permission, throw a SecurityException . |
void |
enforceCallingOrSelfUriPermission(Uri uri, int modeFlags, String message) If the calling process of an IPC or you has not been granted permission to access a specific URI, throw SecurityException . |
void |
enforceCallingPermission(String permission, String message) If the calling process of an IPC you are handling has not been granted a particular permission, throw a SecurityException . |
void |
enforceCallingUriPermission(Uri uri, int modeFlags, String message) If the calling process and user ID has not been granted permission to access a specific URI, throw SecurityException . |
void |
enforcePermission(String permission, int pid, int uid, String message) If the given permission is not allowed for a particular process and user ID running in the system, throw a SecurityException . |
void |
enforceUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags, String message) Enforce both a Uri and normal permission. |
void |
enforceUriPermission(Uri uri, int pid, int uid, int modeFlags, String message) If a particular process and user ID has not been granted permission to access a specific URI, throw SecurityException . |
String[] |
fileList() Returns an array of strings naming the private files associated with this Context's application package. |
Context |
getApplicationContext() Return the context of the single, global Application object of the current process. |
ApplicationInfo |
getApplicationInfo() Return the full application info for this context's package. |
AssetManager |
getAssets() Returns an AssetManager instance for the application's package. |
Context |
getBaseContext() |
File |
getCacheDir() Returns the absolute path to the application specific cache directory on the filesystem. |
ClassLoader |
getClassLoader() Return a class loader you can use to retrieve classes in this package. |
File |
getCodeCacheDir() Returns the absolute path to the application specific cache directory on the filesystem designed for storing cached code. |
ContentResolver |
getContentResolver() Return a ContentResolver instance for your application's package. |
File |
getDataDir() Returns the absolute path to the directory on the filesystem where all private files belonging to this app are stored. |
File |
getDatabasePath(String name) Returns the absolute path on the filesystem where a database created with openOrCreateDatabase(String, int, SQLiteDatabase.CursorFactory) is stored. |
File |
getDir(String name, int mode) Retrieve, creating if needed, a new directory in which the application can place its own custom data files. |
File |
getExternalCacheDir() Returns absolute path to application-specific directory on the primary shared/external storage device where the application can place cache files it owns. |
File[] |
getExternalCacheDirs() Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place cache files it owns. |
File |
getExternalFilesDir(String type) Returns the absolute path to the directory on the primary shared/external storage device where the application can place persistent files it owns. |
File[] |
getExternalFilesDirs(String type) Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place persistent files it owns. |
File[] |
getExternalMediaDirs() Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place media files. |
File |
getFileStreamPath(String name) Returns the absolute path on the filesystem where a file created with openFileOutput(String, int) is stored. |
File |
getFilesDir() Returns the absolute path to the directory on the filesystem where files created with openFileOutput(String, int) are stored. |
Looper |
getMainLooper() Return the Looper for the main thread of the current process. |
File |
getNoBackupFilesDir() Returns the absolute path to the directory on the filesystem similar to getFilesDir() . |
File |
getObbDir() Return the primary shared/external storage directory where this application's OBB files (if there are any) can be found. |
File[] |
getObbDirs() Returns absolute paths to application-specific directories on all shared/external storage devices where the application's OBB files (if there are any) can be found. |
String |
getPackageCodePath() Return the full path to this context's primary Android package. |
PackageManager |
getPackageManager() Return PackageManager instance to find global package information. |
String |
getPackageName() Return the name of this application's package. |
String |
getPackageResourcePath() Return the full path to this context's primary Android package. |
Resources |
getResources() Returns a Resources instance for the application's package. |
SharedPreferences |
getSharedPreferences(String name, int mode) Retrieve and hold the contents of the preferences file 'name', returning a SharedPreferences through which you can retrieve and modify its values. |
Object |
getSystemService(String name) Return the handle to a system-level service by name. |
String |
getSystemServiceName(Class<?> serviceClass) Gets the name of the system-level service that is represented by the specified class. |
Resources.Theme |
getTheme() Return the Theme object associated with this Context. |
Drawable |
getWallpaper() This method was deprecated in API level 23. Use WallpaperManager.get() instead. |
int |
getWallpaperDesiredMinimumHeight() This method was deprecated in API level 23. Use WallpaperManager.getDesiredMinimumHeight() instead. |
int |
getWallpaperDesiredMinimumWidth() This method was deprecated in API level 23. Use WallpaperManager.getDesiredMinimumWidth() instead. |
void |
grantUriPermission(String toPackage, Uri uri, int modeFlags) Grant permission to access a specific Uri to another package, regardless of whether that package has general permission to access the Uri's content provider. |
boolean |
isDeviceProtectedStorage() Indicates if the storage APIs of this Context are backed by device-protected storage. |
boolean |
isRestricted() Indicates whether this Context is restricted. |
boolean |
moveDatabaseFrom(Context sourceContext, String name) Move an existing database file from the given source storage context to this context. |
boolean |
moveSharedPreferencesFrom(Context sourceContext, String name) Move an existing shared preferences file from the given source storage context to this context. |
FileInputStream |
openFileInput(String name) Open a private file associated with this Context's application package for reading. |
FileOutputStream |
openFileOutput(String name, int mode) Open a private file associated with this Context's application package for writing. |
SQLiteDatabase |
openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory, DatabaseErrorHandler errorHandler) Open a new private SQLiteDatabase associated with this Context's application package. |
SQLiteDatabase |
openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory) Open a new private SQLiteDatabase associated with this Context's application package. |
Drawable |
peekWallpaper() This method was deprecated in API level 23. Use WallpaperManager.peek() instead. |
Intent |
registerReceiver(BroadcastReceiver receiver, IntentFilter filter) Register a BroadcastReceiver to be run in the main activity thread. |
Intent |
registerReceiver(BroadcastReceiver receiver, IntentFilter filter, String broadcastPermission, Handler scheduler) Register to receive intent broadcasts, to run in the context of scheduler. |
void |
removeStickyBroadcast(Intent intent) This method was deprecated in API level 23. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
void |
removeStickyBroadcastAsUser(Intent intent, UserHandle user) This method was deprecated in API level 23. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
void |
revokeUriPermission(Uri uri, int modeFlags) Remove all permissions to access a particular content provider Uri that were previously added with grantUriPermission(String, Uri, int) . |
void |
sendBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, allowing an optional required permission to be enforced. |
void |
sendBroadcast(Intent intent) Broadcast the given intent to all interested BroadcastReceivers. |
void |
sendBroadcastAsUser(Intent intent, UserHandle user) Version of sendBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. |
void |
sendBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission) Version of sendBroadcast(Intent, String) that allows you to specify the user the broadcast will be sent to. |
void |
sendOrderedBroadcast(Intent intent, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendBroadcast(Intent) that allows you to receive data back from the broadcast. |
void |
sendOrderedBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, delivering them one at a time to allow more preferred receivers to consume the broadcast before it is delivered to less preferred receivers. |
void |
sendOrderedBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendOrderedBroadcast(Intent, String, BroadcastReceiver, Handler, int, String, Bundle) that allows you to specify the user the broadcast will be sent to. |
void |
sendStickyBroadcast(Intent intent) This method was deprecated in API level 23. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
void |
sendStickyBroadcastAsUser(Intent intent, UserHandle user) This method was deprecated in API level 23. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
void |
sendStickyOrderedBroadcast(Intent intent, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) This method was deprecated in API level 23. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
void |
sendStickyOrderedBroadcastAsUser(Intent intent, UserHandle user, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) This method was deprecated in API level 23. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
void |
setTheme(int resid) Set the base theme for this context. |
void |
setWallpaper(Bitmap bitmap) This method was deprecated in API level 23. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER . |
void |
setWallpaper(InputStream data) This method was deprecated in API level 23. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER . |
void |
startActivities(Intent[] intents, Bundle options) Launch multiple new activities. |
void |
startActivities(Intent[] intents) Same as startActivities(Intent[], Bundle) with no options specified. |
void |
startActivity(Intent intent) Same as startActivity(Intent, Bundle) with no options specified. |
void |
startActivity(Intent intent, Bundle options) Launch a new activity. |
boolean |
startInstrumentation(ComponentName className, String profileFile, Bundle arguments) Start executing an Instrumentation class. |
void |
startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags) Same as startIntentSender(IntentSender, Intent, int, int, int, Bundle) with no options specified. |
void |
startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags, Bundle options) Like startActivity(Intent, Bundle) , but taking a IntentSender to start. |
ComponentName |
startService(Intent service) Request that a given application service be started. |
boolean |
stopService(Intent name) Request that a given application service be stopped. |
void |
unbindService(ServiceConnection conn) Disconnect from an application service. |
void |
unregisterReceiver(BroadcastReceiver receiver) Unregister a previously registered BroadcastReceiver. |
|
From class android.content.Context
abstract boolean |
bindService(Intent service, ServiceConnection conn, int flags) Connect to an application service, creating it if needed. |
abstract int |
checkCallingOrSelfPermission(String permission) Determine whether the calling process of an IPC or you have been granted a particular permission. |
abstract int |
checkCallingOrSelfUriPermission(Uri uri, int modeFlags) Determine whether the calling process of an IPC or you has been granted permission to access a specific URI. |
abstract int |
checkCallingPermission(String permission) Determine whether the calling process of an IPC you are handling has been granted a particular permission. |
abstract int |
checkCallingUriPermission(Uri uri, int modeFlags) Determine whether the calling process and user ID has been granted permission to access a specific URI. |
abstract int |
checkPermission(String permission, int pid, int uid) Determine whether the given permission is allowed for a particular process and user ID running in the system. |
abstract int |
checkSelfPermission(String permission) Determine whether you have been granted a particular permission. |
abstract int |
checkUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags) Check both a Uri and normal permission. |
abstract int |
checkUriPermission(Uri uri, int pid, int uid, int modeFlags) Determine whether a particular process and user ID has been granted permission to access a specific URI. |
abstract void |
clearWallpaper() This method was deprecated in API level 5. Use WallpaperManager.clear() instead. This method requires the caller to hold the permission SET_WALLPAPER . |
abstract Context |
createConfigurationContext(Configuration overrideConfiguration) Return a new Context object for the current Context but whose resources are adjusted to match the given Configuration. |
abstract Context |
createDeviceProtectedStorageContext() Return a new Context object for the current Context but whose storage APIs are backed by device-protected storage. |
abstract Context |
createDisplayContext(Display display) Return a new Context object for the current Context but whose resources are adjusted to match the metrics of the given Display. |
abstract Context |
createPackageContext(String packageName, int flags) Return a new Context object for the given application name. |
abstract String[] |
databaseList() Returns an array of strings naming the private databases associated with this Context's application package. |
abstract boolean |
deleteDatabase(String name) Delete an existing private SQLiteDatabase associated with this Context's application package. |
abstract boolean |
deleteFile(String name) Delete the given private file associated with this Context's application package. |
abstract boolean |
deleteSharedPreferences(String name) Delete an existing shared preferences file. |
abstract void |
enforceCallingOrSelfPermission(String permission, String message) If neither you nor the calling process of an IPC you are handling has been granted a particular permission, throw a SecurityException . |
abstract void |
enforceCallingOrSelfUriPermission(Uri uri, int modeFlags, String message) If the calling process of an IPC or you has not been granted permission to access a specific URI, throw SecurityException . |
abstract void |
enforceCallingPermission(String permission, String message) If the calling process of an IPC you are handling has not been granted a particular permission, throw a SecurityException . |
abstract void |
enforceCallingUriPermission(Uri uri, int modeFlags, String message) If the calling process and user ID has not been granted permission to access a specific URI, throw SecurityException . |
abstract void |
enforcePermission(String permission, int pid, int uid, String message) If the given permission is not allowed for a particular process and user ID running in the system, throw a SecurityException . |
abstract void |
enforceUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags, String message) Enforce both a Uri and normal permission. |
abstract void |
enforceUriPermission(Uri uri, int pid, int uid, int modeFlags, String message) If a particular process and user ID has not been granted permission to access a specific URI, throw SecurityException . |
abstract String[] |
fileList() Returns an array of strings naming the private files associated with this Context's application package. |
abstract Context |
getApplicationContext() Return the context of the single, global Application object of the current process. |
abstract ApplicationInfo |
getApplicationInfo() Return the full application info for this context's package. |
abstract AssetManager |
getAssets() Returns an AssetManager instance for the application's package. |
abstract File |
getCacheDir() Returns the absolute path to the application specific cache directory on the filesystem. |
abstract ClassLoader |
getClassLoader() Return a class loader you can use to retrieve classes in this package. |
abstract File |
getCodeCacheDir() Returns the absolute path to the application specific cache directory on the filesystem designed for storing cached code. |
final int |
getColor(int id) Returns a color associated with a particular resource ID and styled for the current theme. |
final ColorStateList |
getColorStateList(int id) Returns a color state list associated with a particular resource ID and styled for the current theme. |
abstract ContentResolver |
getContentResolver() Return a ContentResolver instance for your application's package. |
abstract File |
getDataDir() Returns the absolute path to the directory on the filesystem where all private files belonging to this app are stored. |
abstract File |
getDatabasePath(String name) Returns the absolute path on the filesystem where a database created with openOrCreateDatabase(String, int, SQLiteDatabase.CursorFactory) is stored. |
abstract File |
getDir(String name, int mode) Retrieve, creating if needed, a new directory in which the application can place its own custom data files. |
final Drawable |
getDrawable(int id) Returns a drawable object associated with a particular resource ID and styled for the current theme. |
abstract File |
getExternalCacheDir() Returns absolute path to application-specific directory on the primary shared/external storage device where the application can place cache files it owns. |
abstract File[] |
getExternalCacheDirs() Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place cache files it owns. |
abstract File |
getExternalFilesDir(String type) Returns the absolute path to the directory on the primary shared/external storage device where the application can place persistent files it owns. |
abstract File[] |
getExternalFilesDirs(String type) Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place persistent files it owns. |
abstract File[] |
getExternalMediaDirs() Returns absolute paths to application-specific directories on all shared/external storage devices where the application can place media files. |
abstract File |
getFileStreamPath(String name) Returns the absolute path on the filesystem where a file created with openFileOutput(String, int) is stored. |
abstract File |
getFilesDir() Returns the absolute path to the directory on the filesystem where files created with openFileOutput(String, int) are stored. |
abstract Looper |
getMainLooper() Return the Looper for the main thread of the current process. |
abstract File |
getNoBackupFilesDir() Returns the absolute path to the directory on the filesystem similar to getFilesDir() . |
abstract File |
getObbDir() Return the primary shared/external storage directory where this application's OBB files (if there are any) can be found. |
abstract File[] |
getObbDirs() Returns absolute paths to application-specific directories on all shared/external storage devices where the application's OBB files (if there are any) can be found. |
abstract String |
getPackageCodePath() Return the full path to this context's primary Android package. |
abstract PackageManager |
getPackageManager() Return PackageManager instance to find global package information. |
abstract String |
getPackageName() Return the name of this application's package. |
abstract String |
getPackageResourcePath() Return the full path to this context's primary Android package. |
abstract Resources |
getResources() Returns a Resources instance for the application's package. |
abstract SharedPreferences |
getSharedPreferences(String name, int mode) Retrieve and hold the contents of the preferences file 'name', returning a SharedPreferences through which you can retrieve and modify its values. |
final String |
getString(int resId, Object... formatArgs) Returns a localized formatted string from the application's package's default string table, substituting the format arguments as defined in Formatter and format(String, Object...) . |
final String |
getString(int resId) Returns a localized string from the application's package's default string table. |
final <T> T |
getSystemService(Class<T> serviceClass) Return the handle to a system-level service by class. |
abstract Object |
getSystemService(String name) Return the handle to a system-level service by name. |
abstract String |
getSystemServiceName(Class<?> serviceClass) Gets the name of the system-level service that is represented by the specified class. |
final CharSequence |
getText(int resId) Return a localized, styled CharSequence from the application's package's default string table. |
abstract Resources.Theme |
getTheme() Return the Theme object associated with this Context. |
abstract Drawable |
getWallpaper() This method was deprecated in API level 5. Use WallpaperManager.get() instead. |
abstract int |
getWallpaperDesiredMinimumHeight() This method was deprecated in API level 5. Use WallpaperManager.getDesiredMinimumHeight() instead. |
abstract int |
getWallpaperDesiredMinimumWidth() This method was deprecated in API level 5. Use WallpaperManager.getDesiredMinimumWidth() instead. |
abstract void |
grantUriPermission(String toPackage, Uri uri, int modeFlags) Grant permission to access a specific Uri to another package, regardless of whether that package has general permission to access the Uri's content provider. |
abstract boolean |
isDeviceProtectedStorage() Indicates if the storage APIs of this Context are backed by device-protected storage. |
boolean |
isRestricted() Indicates whether this Context is restricted. |
abstract boolean |
moveDatabaseFrom(Context sourceContext, String name) Move an existing database file from the given source storage context to this context. |
abstract boolean |
moveSharedPreferencesFrom(Context sourceContext, String name) Move an existing shared preferences file from the given source storage context to this context. |
final TypedArray |
obtainStyledAttributes(AttributeSet set, int[] attrs) Retrieve styled attribute information in this Context's theme. |
final TypedArray |
obtainStyledAttributes(AttributeSet set, int[] attrs, int defStyleAttr, int defStyleRes) Retrieve styled attribute information in this Context's theme. |
final TypedArray |
obtainStyledAttributes(int resid, int[] attrs) Retrieve styled attribute information in this Context's theme. |
final TypedArray |
obtainStyledAttributes(int[] attrs) Retrieve styled attribute information in this Context's theme. |
abstract FileInputStream |
openFileInput(String name) Open a private file associated with this Context's application package for reading. |
abstract FileOutputStream |
openFileOutput(String name, int mode) Open a private file associated with this Context's application package for writing. |
abstract SQLiteDatabase |
openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory, DatabaseErrorHandler errorHandler) Open a new private SQLiteDatabase associated with this Context's application package. |
abstract SQLiteDatabase |
openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory) Open a new private SQLiteDatabase associated with this Context's application package. |
abstract Drawable |
peekWallpaper() This method was deprecated in API level 5. Use WallpaperManager.peek() instead. |
void |
registerComponentCallbacks(ComponentCallbacks callback) Add a new ComponentCallbacks to the base application of the Context, which will be called at the same times as the ComponentCallbacks methods of activities and other components are called. |
abstract Intent |
registerReceiver(BroadcastReceiver receiver, IntentFilter filter) Register a BroadcastReceiver to be run in the main activity thread. |
abstract Intent |
registerReceiver(BroadcastReceiver receiver, IntentFilter filter, String broadcastPermission, Handler scheduler) Register to receive intent broadcasts, to run in the context of scheduler. |
abstract void |
removeStickyBroadcast(Intent intent) This method was deprecated in API level 21. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
abstract void |
removeStickyBroadcastAsUser(Intent intent, UserHandle user) This method was deprecated in API level 21. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
abstract void |
revokeUriPermission(Uri uri, int modeFlags) Remove all permissions to access a particular content provider Uri that were previously added with grantUriPermission(String, Uri, int) . |
abstract void |
sendBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, allowing an optional required permission to be enforced. |
abstract void |
sendBroadcast(Intent intent) Broadcast the given intent to all interested BroadcastReceivers. |
abstract void |
sendBroadcastAsUser(Intent intent, UserHandle user) Version of sendBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. |
abstract void |
sendBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission) Version of sendBroadcast(Intent, String) that allows you to specify the user the broadcast will be sent to. |
abstract void |
sendOrderedBroadcast(Intent intent, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendBroadcast(Intent) that allows you to receive data back from the broadcast. |
abstract void |
sendOrderedBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, delivering them one at a time to allow more preferred receivers to consume the broadcast before it is delivered to less preferred receivers. |
abstract void |
sendOrderedBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendOrderedBroadcast(Intent, String, BroadcastReceiver, Handler, int, String, Bundle) that allows you to specify the user the broadcast will be sent to. |
abstract void |
sendStickyBroadcast(Intent intent) This method was deprecated in API level 21. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
abstract void |
sendStickyBroadcastAsUser(Intent intent, UserHandle user) This method was deprecated in API level 21. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
abstract void |
sendStickyOrderedBroadcast(Intent intent, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) This method was deprecated in API level 21. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
abstract void |
sendStickyOrderedBroadcastAsUser(Intent intent, UserHandle user, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) This method was deprecated in API level 21. Sticky broadcasts should not be used. They provide no security (anyone can access them), no protection (anyone can modify them), and many other problems. The recommended pattern is to use a non-sticky broadcast to report that something has changed, with another mechanism for apps to retrieve the current value whenever desired. |
abstract void |
setTheme(int resid) Set the base theme for this context. |
abstract void |
setWallpaper(Bitmap bitmap) This method was deprecated in API level 5. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER . |
abstract void |
setWallpaper(InputStream data) This method was deprecated in API level 5. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER . |
abstract void |
startActivities(Intent[] intents, Bundle options) Launch multiple new activities. |
abstract void |
startActivities(Intent[] intents) Same as startActivities(Intent[], Bundle) with no options specified. |
abstract void |
startActivity(Intent intent) Same as startActivity(Intent, Bundle) with no options specified. |
abstract void |
startActivity(Intent intent, Bundle options) Launch a new activity. |
abstract boolean |
startInstrumentation(ComponentName className, String profileFile, Bundle arguments) Start executing an Instrumentation class. |
abstract void |
startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags) Same as startIntentSender(IntentSender, Intent, int, int, int, Bundle) with no options specified. |
abstract void |
startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags, Bundle options) Like startActivity(Intent, Bundle) , but taking a IntentSender to start. |
abstract ComponentName |
startService(Intent service) Request that a given application service be started. |
abstract boolean |
stopService(Intent service) Request that a given application service be stopped. |
abstract void |
unbindService(ServiceConnection conn) Disconnect from an application service. |
void |
unregisterComponentCallbacks(ComponentCallbacks callback) Remove a ComponentCallbacks object that was previously registered with registerComponentCallbacks(ComponentCallbacks) . |
abstract void |
unregisterReceiver(BroadcastReceiver receiver) Unregister a previously registered BroadcastReceiver. |
|
From class java.lang.Object
Object |
clone() Creates and returns a copy of this object. |
boolean |
equals(Object obj) Indicates whether some other object is "equal to" this one. |
void |
finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. |
final Class<?> |
getClass() Returns the runtime class of this Object . |
int |
hashCode() Returns a hash code value for the object. |
final void |
notify() Wakes up a single thread that is waiting on this object's monitor. |
final void |
notifyAll() Wakes up all threads that are waiting on this object's monitor. |
String |
toString() Returns a string representation of the object. |
final void |
wait(long millis, int nanos) Causes the current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed. |
final void |
wait(long millis) Causes the current thread to wait until either another thread invokes the notify() method or the notifyAll() method for this object, or a specified amount of time has elapsed. |
final void |
wait() Causes the current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object. |
|
From interface android.content.ComponentCallbacks2
abstract void |
onTrimMemory(int level) Called when the operating system has determined that it is a good time for a process to trim unneeded memory from its process. |
|
From interface android.content.ComponentCallbacks
abstract void |
onConfigurationChanged(Configuration newConfig) Called by the system when the device configuration changes while your component is running. |
abstract void |
onLowMemory() This is called when the overall system is running low on memory, and actively running processes should trim their memory usage. |
|
Constants
START_NOT_STICKY
int START_NOT_STICKY
Constant to return from onStartCommand(Intent, int, int)
: if this service's process is killed while it is started (after returning from onStartCommand(Intent, int, int)
), and there are no new start intents to deliver to it, then take the service out of the started state and don't recreate until a future explicit call to Context.startService(Intent)
. The service will not receive a onStartCommand(Intent, int, int)
call with a null Intent because it will not be re-started if there are no pending Intents to deliver.
This mode makes sense for things that want to do some work as a result of being started, but can be stopped when under memory pressure and will explicit start themselves again later to do more work. An example of such a service would be one that polls for data from a server: it could schedule an alarm to poll every N minutes by having the alarm start its service. When its onStartCommand(Intent, int, int)
is called from the alarm, it schedules a new alarm for N minutes later, and spawns a thread to do its networking. If its process is killed while doing that check, the service will not be restarted until the alarm goes off.
Constant Value: 2 (0x00000002)
START_REDELIVER_INTENT
int START_REDELIVER_INTENT
Constant to return from onStartCommand(Intent, int, int)
: if this service's process is killed while it is started (after returning from onStartCommand(Intent, int, int)
), then it will be scheduled for a restart and the last delivered Intent re-delivered to it again via onStartCommand(Intent, int, int)
. This Intent will remain scheduled for redelivery until the service calls stopSelf(int)
with the start ID provided to onStartCommand(Intent, int, int)
. The service will not receive a onStartCommand(Intent, int, int)
call with a null Intent because it will will only be re-started if it is not finished processing all Intents sent to it (and any such pending events will be delivered at the point of restart).
Constant Value: 3 (0x00000003)
START_STICKY
int START_STICKY
Constant to return from onStartCommand(Intent, int, int)
: if this service's process is killed while it is started (after returning from onStartCommand(Intent, int, int)
), then leave it in the started state but don't retain this delivered intent. Later the system will try to re-create the service. Because it is in the started state, it will guarantee to call onStartCommand(Intent, int, int)
after creating the new service instance; if there are not any pending start commands to be delivered to the service, it will be called with a null intent object, so you must take care to check for this.
This mode makes sense for things that will be explicitly started and stopped to run for arbitrary periods of time, such as a service performing background music playback.
Constant Value: 1 (0x00000001)
STOP_FOREGROUND_DETACH
int STOP_FOREGROUND_DETACH
Flag for stopForeground(int)
: if set, the notification previously provided to startForeground(int, Notification)
will be detached from the service. Only makes sense when STOP_FOREGROUND_REMOVE
is not set -- in this case, the notification will remain shown, but be completely detached from the service and so no longer changed except through direct calls to the notification manager.
Constant Value: 2 (0x00000002)
Public constructors
Public methods
getApplication
Application getApplication ()
Return the application that owns this service.
onBind
IBinder onBind (Intent intent)
Return the communication channel to the service. May return null if clients can not bind to the service. The returned IBinder
is usually for a complex interface that has been described using aidl.
Note that unlike other application components, calls on to the IBinder interface returned here may not happen on the main thread of the process. More information about the main thread can be found in Processes and Threads.
Parameters |
intent |
Intent : The Intent that was used to bind to this service, as given to Context.bindService . Note that any extras that were included with the Intent at that point will not be seen here. |
Returns |
IBinder |
Return an IBinder through which clients can call on to the service. |
onConfigurationChanged
void onConfigurationChanged (Configuration newConfig)
Called by the system when the device configuration changes while your component is running. Note that, unlike activities, other components are never restarted when a configuration changes: they must always deal with the results of the change, such as by re-retrieving resources.
At the time that this function has been called, your Resources object will have been updated to return resource values matching the new configuration.
For more information, read Handling Runtime Changes.
Parameters |
newConfig |
Configuration : The new device configuration. |
onCreate
void onCreate ()
Called by the system when the service is first created. Do not call this method directly.
onDestroy
void onDestroy ()
Called by the system to notify a Service that it is no longer used and is being removed. The service should clean up any resources it holds (threads, registered receivers, etc) at this point. Upon return, there will be no more calls in to this Service object and it is effectively dead. Do not call this method directly.
onLowMemory
void onLowMemory ()
This is called when the overall system is running low on memory, and actively running processes should trim their memory usage. While the exact point at which this will be called is not defined, generally it will happen when all background process have been killed. That is, before reaching the point of killing processes hosting service and foreground UI that we would like to avoid killing.
You should implement this method to release any caches or other unnecessary resources you may be holding on to. The system will perform a garbage collection for you after returning from this method.
Preferably, you should implement onTrimMemory(int)
from ComponentCallbacks2
to incrementally unload your resources based on various levels of memory demands. That API is available for API level 14 and higher, so you should only use this onLowMemory()
method as a fallback for older versions, which can be treated the same as onTrimMemory(int)
with the TRIM_MEMORY_COMPLETE
level.
onRebind
void onRebind (Intent intent)
Called when new clients have connected to the service, after it had previously been notified that all had disconnected in its onUnbind(Intent)
. This will only be called if the implementation of onUnbind(Intent)
was overridden to return true.
Parameters |
intent |
Intent : The Intent that was used to bind to this service, as given to Context.bindService . Note that any extras that were included with the Intent at that point will not be seen here. |
onStartCommand
int onStartCommand (Intent intent,
int flags,
int startId)
Called by the system every time a client explicitly starts the service by calling startService(Intent)
, providing the arguments it supplied and a unique integer token representing the start request. Do not call this method directly.
For backwards compatibility, the default implementation calls onStart(Intent, int)
and returns either START_STICKY
or START_STICKY_COMPATIBILITY
.
If you need your application to run on platform versions prior to API level 5, you can use the following model to handle the older onStart(Intent, int)
callback in that case. The handleCommand
method is implemented by you as appropriate:
// This is the old onStart method that will be called on the pre-2.0
// platform. On 2.0 or later we override onStartCommand() so this
// method will not be called.
@Override
public void onStart(Intent intent, int startId) {
handleCommand(intent);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
handleCommand(intent);
// We want this service to continue running until it is explicitly
// stopped, so return sticky.
return START_STICKY;
}
Note that the system calls this on your service's main thread. A service's main thread is the same thread where UI operations take place for Activities running in the same process. You should always avoid stalling the main thread's event loop. When doing long-running operations, network calls, or heavy disk I/O, you should kick off a new thread, or use AsyncTask
.
Returns |
int |
The return value indicates what semantics the system should use for the service's current started state. It may be one of the constants associated with the START_CONTINUATION_MASK bits. |
onTaskRemoved
void onTaskRemoved (Intent rootIntent)
This is called if the service is currently running and the user has removed a task that comes from the service's application. If you have set ServiceInfo.FLAG_STOP_WITH_TASK
then you will not receive this callback; instead, the service will simply be stopped.
Parameters |
rootIntent |
Intent : The original root Intent that was used to launch the task that is being removed. |
onTrimMemory
void onTrimMemory (int level)
Called when the operating system has determined that it is a good time for a process to trim unneeded memory from its process. This will happen for example when it goes in the background and there is not enough memory to keep as many background processes running as desired. You should never compare to exact values of the level, since new intermediate values may be added -- you will typically want to compare if the value is greater or equal to a level you are interested in.
To retrieve the processes current trim level at any point, you can use ActivityManager.getMyMemoryState(RunningAppProcessInfo)
.
onUnbind
boolean onUnbind (Intent intent)
Called when all clients have disconnected from a particular interface published by the service. The default implementation does nothing and returns false.
Parameters |
intent |
Intent : The Intent that was used to bind to this service, as given to Context.bindService . Note that any extras that were included with the Intent at that point will not be seen here. |
Returns |
boolean |
Return true if you would like to have the service's onRebind(Intent) method later called when new clients bind to it. |
startForeground
void startForeground (int id,
Notification notification)
Make this service run in the foreground, supplying the ongoing notification to be shown to the user while in this state. By default services are background, meaning that if the system needs to kill them to reclaim more memory (such as to display a large page in a web browser), they can be killed without too much harm. You can set this flag if killing your service would be disruptive to the user, such as if your service is performing background music playback, so the user would notice if their music stopped playing.
If you need your application to run on platform versions prior to API level 5, you can use the following model to call the the older setForeground() or this modern method as appropriate:
private static final Class<?>[] mSetForegroundSignature = new Class[] {
boolean.class};
private static final Class<?>[] mStartForegroundSignature = new Class[] {
int.class, Notification.class};
private static final Class<?>[] mStopForegroundSignature = new Class[] {
boolean.class};
private NotificationManager mNM;
private Method mSetForeground;
private Method mStartForeground;
private Method mStopForeground;
private Object[] mSetForegroundArgs = new Object[1];
private Object[] mStartForegroundArgs = new Object[2];
private Object[] mStopForegroundArgs = new Object[1];
void invokeMethod(Method method, Object[] args) {
try {
method.invoke(this, args);
} catch (InvocationTargetException e) {
// Should not happen.
Log.w("ApiDemos", "Unable to invoke method", e);
} catch (IllegalAccessException e) {
// Should not happen.
Log.w("ApiDemos", "Unable to invoke method", e);
}
}
/**
* This is a wrapper around the new startForeground method, using the older
* APIs if it is not available.
*/
void startForegroundCompat(int id, Notification notification) {
// If we have the new startForeground API, then use it.
if (mStartForeground != null) {
mStartForegroundArgs[0] = Integer.valueOf(id);
mStartForegroundArgs[1] = notification;
invokeMethod(mStartForeground, mStartForegroundArgs);
return;
}
// Fall back on the old API.
mSetForegroundArgs[0] = Boolean.TRUE;
invokeMethod(mSetForeground, mSetForegroundArgs);
mNM.notify(id, notification);
}
/**
* This is a wrapper around the new stopForeground method, using the older
* APIs if it is not available.
*/
void stopForegroundCompat(int id) {
// If we have the new stopForeground API, then use it.
if (mStopForeground != null) {
mStopForegroundArgs[0] = Boolean.TRUE;
invokeMethod(mStopForeground, mStopForegroundArgs);
return;
}
// Fall back on the old API. Note to cancel BEFORE changing the
// foreground state, since we could be killed at that point.
mNM.cancel(id);
mSetForegroundArgs[0] = Boolean.FALSE;
invokeMethod(mSetForeground, mSetForegroundArgs);
}
@Override
public void onCreate() {
mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
try {
mStartForeground = getClass().getMethod("startForeground",
mStartForegroundSignature);
mStopForeground = getClass().getMethod("stopForeground",
mStopForegroundSignature);
return;
} catch (NoSuchMethodException e) {
// Running on an older platform.
mStartForeground = mStopForeground = null;
}
try {
mSetForeground = getClass().getMethod("setForeground",
mSetForegroundSignature);
} catch (NoSuchMethodException e) {
throw new IllegalStateException(
"OS doesn't have Service.startForeground OR Service.setForeground!");
}
}
@Override
public void onDestroy() {
handleDestroy();
// Make sure our notification is gone.
stopForegroundCompat(R.string.foreground_service_started);
}
stopForeground
void stopForeground (int flags)
Remove this service from foreground state, allowing it to be killed if more memory is needed.
stopForeground
void stopForeground (boolean removeNotification)
Synonym for stopForeground(int)
.
stopSelf
void stopSelf ()
Stop the service, if it was previously started. This is the same as calling stopService(Intent)
for this particular service.
stopSelf
void stopSelf (int startId)
Old version of stopSelfResult(int)
that doesn't return a result.
stopSelfResult
boolean stopSelfResult (int startId)
Stop the service if the most recent time it was started was startId. This is the same as calling stopService(Intent)
for this particular service but allows you to safely avoid stopping if there is a start request from a client that you haven't yet seen in onStart(Intent, int)
.
Be careful about ordering of your calls to this function.. If you call this function with the most-recently received ID before you have called it for previously received IDs, the service will be immediately stopped anyway. If you may end up processing IDs out of order (such as by dispatching them on separate threads), then you are responsible for stopping them in the same order you received them.
Returns |
boolean |
Returns true if the startId matches the last start request and the service will be stopped, else false. |
Protected methods
dump
void dump (FileDescriptor fd,
PrintWriter writer,
String[] args)
Print the Service's state into the given stream. This gets invoked if you run "adb shell dumpsys activity service <yourservicename>" (note that for this command to work, the service must be running, and you must specify a fully-qualified service name). This is distinct from "dumpsys <servicename>", which only works for named system services and which invokes the dump(FileDescriptor, String[])
method on the IBinder
interface registered with ServiceManager.
Parameters |
fd |
FileDescriptor : The raw file descriptor that the dump is being sent to. |
writer |
PrintWriter : The PrintWriter to which you should dump your state. This will be closed for you after you return. |
args |
String : additional arguments to the dump request. |