android-wakelock-example

Make sure that your android device has no security options and the following settings set no none,

Settings->Security->Screen Lock->None

This is a sample of android wake lock to turn on the screen when it's triggered.

    //import the following package
    import android.os.PowerManager;
    
    
    PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
    PowerManager.WakeLock wakeLock; = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK |
            PowerManager.ACQUIRE_CAUSES_WAKEUP |
            PowerManager.ON_AFTER_RELEASE, "app::WakeLock");

    //acquire will turn on the display
    wakeLock.acquire();

    //release will release the lock from CPU, in case of that, screen will go back to sleep mode in defined time bt device settings
    wakeLock.release();

make sure the following line included to your manifest file.

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

Full Source Code is Here

    package com.example.wakelocksample;

    import androidx.appcompat.app.AppCompatActivity;
    import android.os.Bundle;
    import android.os.PowerManager;
    import org.w3c.dom.Text;

    public class MainActivity extends AppCompatActivity {

     PowerManager.WakeLock wakeLock;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.activity_main);


    PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
    wakeLock = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK |
            PowerManager.ACQUIRE_CAUSES_WAKEUP |
            PowerManager.ON_AFTER_RELEASE, "app::WakeLock");

    //acquire will turn on the display
    wakeLock.acquire();

    //release will release the lock from CPU, in case of that, screen will go back to sleep mode in defined time bt device settings
    wakeLock.release();


    }
    }