Activating the Display via PowerManager

1. Manifest Permission

Declare the necessary permission in the AndroidManifest file to allow the application to control the screen state.

<uses-permission android:name="android.permission.WAKE_LOCK" />

2. WakeLock Initialization

Retrieve the PowerManager system service and create a WakeLock instance specifying the desired screen state flags.

private PowerManager powerManager;
private WakeLock screenWakeLock;

private void initializeScreenWake(Context appContext) {
    if (appContext == null) return;
    powerManager = (PowerManager) appContext.getSystemService(Context.POWER_SERVICE);
    screenWakeLock = powerManager.newWakeLock(
        PowerManager.ACQUIRE_CAUSES_WAKEUP | 
        PowerManager.FULL_WAKE_LOCK | 
        PowerManager.ON_AFTER_RELEASE, 
        "MyApp:ScreenActivationTag"
    );
}

3. Acquiring and Releasing the Lock

Invoke the acquire method to turn the screen on, passing a timeout to prevent indefinite locking. Always ensure that acquire and release operations are executed in pairs to avoid battery drain.

// Force the screen to turn on
screenWakeLock.acquire(2000L);

// Relinquish control when no longer needed
if (screenWakeLock.isHeld()) {
    screenWakeLock.release();
}

Maintaining Persistent Screen Illumination

1. Layout XML Attribute

The simplest approach requires no code adjustments. Apply the following attribute directly to any view element within your layout XML.

android:keepScreenOn="true"

2. Window Flags Configuration

Alternatively, set the window flags programmatically before setting the content view. This method avoids requiring the WAKE_LOCK permission and will not prompt the user during installation.

getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

Simulating Touch Events via Shell Commands

If the application process remains active, dispatching a simulated tap event can wake the display. This technique relies on executing shell instructions.

public class InputEventSimulator {

    public void triggerTapByRatio(Context context, float percentX, float percentY) {
        WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
        Point displaySize = new Point();
        windowManager.getDefaultDisplay().getSize(displaySize);

        int coordinateX = (int) (displaySize.x * percentX);
        int coordinateY = (int) (displaySize.y * percentY);

        executeShellTap(coordinateX, coordinateY);
    }

    public void triggerTapAtPosition(int posX, int posY) {
        executeShellTap(posX, posY);
    }

    private void executeShellTap(final int targetX, final int targetY) {
        new Thread(() -> {
            try {
                Thread.sleep(150);
                Runtime.getRuntime().exec(new String[]{"input", "tap", String.valueOf(targetX), String.valueOf(targetY)});
            } catch (Exception err) {
                err.printStackTrace();
            }
        }).start();
    }
}

Implementation Example

private InputEventSimulator eventSimulator = new InputEventSimulator();

// Trigger a tap at absolute coordinates
eventSimulator.triggerTapAtPosition(840, 580);