IntentService

Creates an IntentService. Invoked by your subclass's constructor.

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 this can be found in Application Fundamentals: Processes and Threads.

Called by the system when the service is first created. Do not call this method directly.

Called by the system to notify a Service that it is no longer used and is being removed. The service should clean up an 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.

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.

Sets intent redelivery preferences. Usually called from the constructor with your preferred semantics.

If enabled is true, onStartCommand(Intent, int, int) will return START_REDELIVER_INTENT, so if this process dies before onHandleIntent(Intent) returns, the process will be restarted and the intent redelivered. If multiple Intents have been sent, only the most recent one is guaranteed to be redelivered.

If enabled is false (the default), onStartCommand(Intent, int, int) will return START_NOT_STICKY, and if the process dies, the Intent dies along with it.

This method is invoked on the worker thread with a request to process. Only one Intent is processed at a time, but the processing happens on a worker thread that runs independently from other application logic. So, if this code takes a long time, it will hold up other requests to the same IntentService, but it will not hold up anything else.