Android - detect phone unlock event, not screen on

Here's what to do:

Say you want to detect the unlock event and do something in your activity when the phone is unlocked. Have a Broadcast Receiver for ACTION_SCREEN_ON, ACTION_SCREEN_OFF and ACTION_USER_PRESENT.

onResume of the activity will be called when ACTION_SCREEN_ON is fired. Create a handler and wait for ACTION_USER_PRESENT. When it is fired, implement what you want for your activity.

Credit goes to CommonsWare's answer here: Android -- What happens when device is unlocked?


After struggling with this for a while, I've found that the best way to do this is to register a BroadcastReceiver on the "android.intent.action.USER_PRESENT" action.

"Broadcast Action: Sent when the user is present after device wakes up (e.g when the key-guard is gone)."

To distinguish between cases where the user has turned on phone screen when it wasn't locked, and when they actually unlocked it use the KeyguardManager to check the security settings.

Code example:

Add this to your activity:

registerReceiver(new PhoneUnlockedReceiver(), new IntentFilter("android.intent.action.USER_PRESENT"));

Then use this class:

public class PhoneUnlockedReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {

        KeyguardManager keyguardManager = (KeyguardManager)context.getSystemService(Context.KEYGUARD_SERVICE);
        if (keyguardManager.isKeyguardSecure()) {
            //phone was unlocked, do stuff here
        }
    }
}       

public class PhoneUnlockedReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent.getAction().equals(Intent.ACTION_USER_PRESENT)){
            Log.d(TAG, "Phone unlocked");
        }else if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)){
            Log.d(TAG, "Phone locked");
        }
    }
}

register receiver by this statement

receiver = new PhoneUnlockedReceiver();
        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_USER_PRESENT);
        filter.addAction(Intent.ACTION_SCREEN_OFF);
        registerReceiver(receiver, filter);

Didn't test it but try the following:

  • Wait for ACTION_SCREEN_ON.
  • (After screen is on,) Wait for ACTION_MAIN with category CATEGORY_HOME (Which launches the home screen) - This is probably what is sent after the phone gets unlocked.

The 1st step is needed to filter out regular HOME key presses.