Android 保持屏幕常亮

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

public class test extends Activity
 {
     PowerManager powerManager = null;
     WakeLock wakeLock = null;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
        this.setContentView(R.layout.main);
         
         this.powerManager = (PowerManager)this.getSystemService(Context.POWER_SERVICE);
         this.wakeLock = this.powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK, "My Lock");
     }
     @Override
     protected void onResume() {
         super.onResume();
         this.wakeLock.acquire();
     }
     @Override
     protected void onPause() {
         super.onPause();
         this.wakeLock.release();
     }
}