shayla.sawchenko.net
While attempting to put some power management features in place, I came upon the need to know if and when the screen on the device was turned off and turned back on again. Turns out there is are two handy intent broadcasts that you can listen for that suited my needs perfectly: Intent.ACTION_SCREEN_OFF and Intent.ACTION_SCREEN_ON.
In my Service I created a private BroadcastReceiver, however, feel free to extract this out to a separate class.
// 1. Create the BroadcastReceiver (within my Service class)
private class ScreenBroadcastReciever extends BroadcastReceiver {
// Query this to know at a given point in time the state of the screen
private boolean mIsScreenOn;
public boolean isScreenOn() {
return mIsScreenOn;
}
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
mIsScreenOn = false;
// Do stuff here when screen goes off
// In my case, stop my service from repeating
}
else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
mIsScreenOn = true;
// Do stuff here when screen goes on
// In my case, start my service repeating
}
}
}
// 2. Define an instance of the BroadcastReceiver
private ScreenBroadcastReciever mScreenReceiver;
// 3. Instantiate and register the BroadcastReceiver
// Note: onResume appears to be called before ScreenBroadcastReciever.onReceive.
// To ensure that we always catch the broadcast, we want to register it in onCreate.
// Even if registering from within an Activity, do so from onCreate.
@Override
public void onCreate() {
// Setup and register receiver filtering on our two Intents
mScreenReceiver = new ScreenBroadcastReciever();
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
filter.addAction(Intent.ACTION_SCREEN_OFF);
registerReceiver(mScreenReceiver, filter);
}
// 4. Unregister the BroadcastReceiver
@Override
public void onDestroy() {
super.onDestroy();
unregisterReceiver(mScreenReceiver);
}
by Shayla Sawchenko
