Keep the screen on

Certain apps need to keep the screen turned on, such as games or movie apps. Some Android APIs automatically keep the screen on for you. In other cases, you can use a Compose modifier or set a flag to manually keep the screen on.

Keep the screen on in Compose

If your app uses Jetpack Compose, apply the keepScreenOn modifier to a composable. The modifier is available in Compose UI 1.9.0 and higher. The screen stays on as long as the modifier is part of the composition. When no composable uses the modifier, Compose stops keeping the screen on automatically.

To keep the screen on only some of the time, apply the modifier conditionally. The following example keeps the screen on only while a video plays:

@Composable
fun VideoPlayer(isPlaying: Boolean, modifier: Modifier = Modifier) {
    Box(
        modifier = modifier
            // Keep the screen on only while the video plays.
            .then(if (isPlaying) Modifier.keepScreenOn() else Modifier)
    ) {
        // Video surface and playback controls.
    }
}

The modifier sets the same view property as the android:keepScreenOn attribute described in the next section, so it keeps the screen on only while your app's window is visible. It doesn't clear a FLAG_KEEP_SCREEN_ON flag that your app sets on the window.

Manually keep the screen on

To keep the device's screen on, set the FLAG_KEEP_SCREEN_ON flag in your activity. This flag may only be set in an activity, never in a service or other app component. For example:

class MainActivity : Activity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
    }
}

Another way to keep the screen on is by setting the the android:keepScreenOn attribute in your application's layout XML file:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:keepScreenOn="true">
    ...
</RelativeLayout>

Using android:keepScreenOn="true" is equivalent to using FLAG_KEEP_SCREEN_ON. You can use whichever approach is best for your app. The advantage of setting the flag programmatically in your activity is that it gives you the option of programmatically clearing the flag later and thereby allowing the screen to turn off.

If an app with the FLAG_KEEP_SCREEN_ON flag goes into the background, the system allows the screen to turn off normally. You don't need to explicitly clear the flag in this case. If your app no longer needs to keep the screen on, you should clear the flag. by calling clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON).

Ambient Mode for TV

On TV devices, use FLAG_KEEP_SCREEN_ON to prevent the device from going into Ambient Mode during active video playback. If the foreground activity does not set FLAG_KEEP_SCREEN_ON, the device automatically enters Ambient Mode after a period of inactivity.

See also