Android has the Hardware button for controlling volume (increase/decrease). I want to same functionality by using buttons in my application with visual volume control and it should be disappeared after some time (in sec).
You need to use the AudioManager class. Developer doc is here. Depending on which volume you want to adjust (ringer/media) you may need to change the audiomode via AudioManager.
Finally, to make the buttons disappear just use View.GONE on them. I would create a Runnable in the onClickListener and use a postDelayed to make the View disappear.
来源：https://stackoverflow.com/questions/5117051/how-to-control-volume-in-android