Android Development: Changing Screen Brightness in Service

问题

Now i do try again.

I want to change the screen brightness.

I've Tried:

WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
layoutParams.screenBrightness = 0.5F; // set 50% brightness
getWindow().setAttributes(layoutParams);

and seems to work in activity but when I am in service i get that getWindow() compile error.

回答1:

A service cannot change the screen brightness that way. A service does not have a user interface, so it does not have Window.

You can try to change the brightness system-wide via the SCREEN_BRIGHTNESS system setting. I have no idea if this works, as I have not tried it.

Otherwise, modify your activities to change their brightness.

回答2:

You would need to start an activity from your service, all you need to do is this:

Intent myIntent = new Intent(getBaseContext(), MyActivity.class);
getApplication().startActivity(myIntent);

where MyActivity is the activity which you want to start. Inside that activity you can put code to change the window brightness, it will work.

I've included the complete code here: https://stackoverflow.com/a/9848456/1204377

Let me know if it's still unclear.

来源：https://stackoverflow.com/questions/6565054/android-development-changing-screen-brightness-in-service