AudioPlayer

public class MainActivity extends AppCompatActivity {

    //set up MediaPlayer
    MediaPlayer mp = new MediaPlayer();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button stop = findViewById(R.id.stop);
        stop.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mp.reset();
            }
        });


        Button button1 = (Button) findViewById(R.id.button1);
        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                    playAudio(R.raw.aa);
            }
        });

    }


    private void playAudio(final int path) {
        mp.reset();
        mp = MediaPlayer.create(getApplicationContext(), path);
        mp.start();
        Toast.makeText(MainActivity.this, "playing",
                Toast.LENGTH_SHORT).show();
    }
}