Android通过服务调整系统亮度

Question

I'm relatively new to Android development. I've been able to adjust screen brightness of my own app by doing things like this:

WindowManager.LayoutParams layout = getWindow().getAttributes();
layout.screenBrightness = 0;
getWindow().setAttributes(layout);

What I really need to do though is change the screen brightness on a system level. I'd like to do this from a Service or Intent Service. The issue I'm running into is that

getWindow()

fails when you call it from a Service. I think this may be possible through the use of ViewOverlays or something but everything I've tried so far has failed. Does anyone have an idea?

I need a solution where my app starts a service in the background and then that service adjusts the screen brightness as you use the device in other apps or on the home screen.

Answer 1

You can try this :

android.provider.Settings.System.putInt(getContentResolver(),
                android.provider.Settings.System.SCREEN_BRIGHTNESS,
                value);

add this to manifest

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

and check for run-time permission like this

   ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.WRITE_SETTINGS}, 1);
        public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
            switch (requestCode) {
                case 1: {
                    if (grantResults.length > 0
                            && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                        //permission accepted

                    } else {
                        // permission denied,
                    }
                    return;
                }

            }
        }