To programmatically set or change Android Button background color, we may call pass the method Button.setBackgroundColor on the button reference and pass Color object as argument. The Android system allows you to customize the default Keyboard app language (keyboard layout), even you can add multiple keyboard languages at the same time. By default, pressing the volume control modifies the volume of the active audio stream. If your app isn't currently playing anything, hitting the volume keys adjusts the music volume (or the ringer volume before Android 9). Unless your app is an alarm clock, you should play audio with usage AudioAttributes.USAGE_MEDIA.