Brightness Screen Filter

Get an instance of WindowManager.

WindowManager windowManager = (WindowManager) Class.forName("android.view.WindowManagerImpl").getMethod("getDefault", new Class[0]).invoke(null, new Object[0]);

Create a full screen layout xml(layout parameters set to fill_parent)

Set your view as not clickable, not focusable, not long clickable, etc so that touch is passed through to your app and the app can detect it.

view.setFocusable(false);
view.setClickable(false);
view.setKeepScreenOn(false);
view.setLongClickable(false);
view.setFocusableInTouchMode(false);

Create a layout parameter of type android.view.WindowManager.LayoutParams. LayoutParams layoutParams = new LayoutParams();

Set layout parameter like height, width etc

layoutParams.height = LayoutParams.FILL_PARENT; 
layoutParams.width = LayoutParams.FILL_PARENT;
layoutParams.flags = 280; // You can try LayoutParams.FLAG_FULLSCREEN too
layoutParams.format = PixelFormat.TRANSLUCENT; // You can try different formats
layoutParams.windowAnimations = android.R.style.Animation_Toast; // You can use only animations that the system to can access
layoutParams.type = LayoutParams.TYPE_SYSTEM_OVERLAY;
layoutParams.gravity = Gravity.BOTTOM;
layoutParams.x = 0;
layoutParams.y = 0;
layoutParams.verticalWeight = 1.0F;
layoutParams.horizontalWeight = 1.0F;
layoutParams.verticalMargin = 0.0F;
layoutParams.horizontalMargin = 0.0F;

Key step: You can set what percentage of brightness you need. layoutParams.setBackgroundDrawable(getBackgroundDrawable(i));

private Drawable getBackgroundDrawable(int i) {
int j = 255 - (int) Math.round(255D * Math.exp(4D * ((double) i / 100D) - 4D));
return new ColorDrawable(Color.argb(j, 0, 0, 0));}

Finally add view to windowManager that you c