Check out example codes for "play mp3 android java". It will help you in understanding the concepts better.
Code Example 1
MediaPlayer mediaPlayer; //In the onCreate Method mediaPlayer = MediaPlayer.create(this, R.raw.alarmclockbuzzer); //Sound file goes in "raw" folder in "res" folder mediaPlayer.start(); //plays the mp3 sound (doesn't need to be in oncreate)
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