java - 停止在 backpress 上播放音频

Question

当我点击播放按钮并播放 mp3 声音时，我有一个 Activity 。当我单击返回时，音频仍在后台播放，并且还可以与其他令人讨厌的音频一起运行。我已尝试实现此处使用的其他方法，但无济于事。

代码:

public class InstructionsManualActivity extends AppCompatActivity {


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_instructions_manual);
    Button one = (Button) this.findViewById(R.id.instructionsManual_but);
    final MediaPlayer mp = MediaPlayer.create(this, R.raw.instructions_manual);
    one.setOnClickListener(new View.OnClickListener() {

        public void onClick(View v) {
            mp.start();
        }
    });
}

}

我试过这段代码，但应用程序在返回时崩溃

@Override
public void onBackPressed() {
    super.onBackPressed();
    if (mp.isPlaying()) {
        mp.stop(); // or mp.pause();
        mp.release();

Answer 1

首先全局声明MediaPlayer对象

  MediaPlayer mp = null;  //Declaring globally so can access anywhere in activity.

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_instructions_manual);
        Button one = (Button) this.findViewById(R.id.instructionsManual_but);
        mp = MediaPlayer.create(this, R.raw.instructions_manual);
        one.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                mp.start();
            }
        });
    }

When you are pressing back button in any activity onBackPressed() will be called , there you can stop you media player if playing.

 @Override
    public void onBackPressed() {
        super.onBackPressed();
       //Here you can stop your MediaPlayer
        if (mp != null && mp.isPlaying()) {
            mp.stop();
            mp.release();
        }
    }