Can't apply system screen brightness programmatically in Android
android, brightness, settings, system
Solution
OK, found the answer here: Refreshing the display from a widget?
Basically, have to make a transparent activity that processes the brightness change. What's not mentioned in the post is that you have to do:
Settings.System.putInt(y.getContentResolver(),Settings.System.SCREEN_BRIGHTNESS_MODE, 0);
Settings.System.putInt(y.getContentResolver(),Settings.System.SCREEN_BRIGHTNESS, brightnessLevel);
then do
WindowManager.LayoutParams lp = getWindow().getAttributes();
lp.screenBrightness = brightness;
getWindow().setAttributes(lp);
And if you call finish() right after applying the changes, brightness will never actually change because the layout has to be created before the brightness settings is applied. So I ended up creating a thread that had a 300ms delay, then called finish().
Problem
I'm using the following to set the system auto brightness mode and level: ``` android.provider.Settings.System.putInt(y.getContentResolver(),Settings.System.SCREEN_BRIGHTNESS_MODE, 0); android.provider.Settings.System.putInt(y.getContentResolver(),Settings.System.SCREEN_BRIGHTNESS, y.brightness1); ``` I can change auto-brighess on and off, and set different levels. The settings seem to be applied properly -- I can go to into Settings --> Display --> Brightness, and whanever setting I set is actually shown correctly. However, the actual screen isn't changing its brightness. If i just tap on the slider in Display Settings, then everything gets applied. I shoudl mention that I'm running an app withat a main activity, and these settings are getting applied in the BroadcastReceiver. I did try to create a dummy activity and tested the stuff there, but got the same results.