Question

我有一组活动代码。我有一个应用程序，有超过10个活动。而且我希望它有一个不断的背景音乐，每当我去另一个活动时它就会停止。当我在这个活动中（也在其他活动中）当我点击Emu或设备的主页按钮，然后返回应用程序时，我将“强制关闭”希望你可以帮助我。三江源

public class AdvancedKids extends Activity implements OnClickListener {

 MediaPlayer yourStereo;
    AssetFileDescriptor afd;


public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.advancelay);


    View numbers = this.findViewById(R.id.button1);
    numbers.setOnClickListener(this);

    View alphabets = this.findViewById(R.id.button2);
    alphabets.setOnClickListener(this);

    View colors = this.findViewById(R.id.button3);
    colors.setOnClickListener(this);

    View shapes = this.findViewById(R.id.button4);
    shapes.setOnClickListener(this);

    View back= this.findViewById(R.id.buttonback);
    back.setOnClickListener(this);

    try {
        // Read the music file from the asset folder
        afd = getAssets().openFd("haha.mp3");
        // Creation of new media player;
        yourStereo = new MediaPlayer();
        // Set the player music source.
        yourStereo.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(),afd.getLength());
        // Set the looping and play the music.
        yourStereo.setLooping(true);
        yourStereo.prepare();
        yourStereo.start();
        } catch (IOException e) {
        e.printStackTrace();
        }

}
        public void onPause() {

            super.onPause();
            yourStereo.pause();
            }

            public void onResume() {
            super.onResume();
            yourStereo.start();
            }


            protected void onStop() {
            super.onStop();
            yourStereo.stop();
            yourStereo = null;
            }
            @Override
            public void onBackPressed(){

              new AlertDialog.Builder(this).setIcon(android.R.drawable.ic_dialog_alert).setTitle("Exit")
              .setMessage("Are you sure you want to exit?")
               .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                                       @Override
                                       public void onClick(DialogInterface dialog, int which) {
                                           Intent intent = new Intent(Intent.ACTION_MAIN);
                                          intent.addCategory(Intent.CATEGORY_HOME);
                                          intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                                          startActivity(intent);
                                          System.exit(0);
                                       }
             }).setNegativeButton("No", null).show();
            }               

public void onClick(View v) {

    switch(v.getId()){
    case R.id.button1:
        Intent button1 = new Intent(this, Numbers.class);
        startActivity(button1);
        break;

    case R.id.button2:
        Intent button2 = new Intent(this, Alphabets.class);
        startActivity(button2);
        break;

    case R.id.button3:
        Intent button3 = new Intent(this, Colors.class);
        startActivity(button3);
        break;

    case R.id.button4:
        Intent button4 = new Intent(this, Shapes.class);
        startActivity(button4);
        break;

    case R.id.buttonback:
        Intent buttonback = new Intent(this, MainActivity.class);
        startActivity(buttonback);
        break;



    }  

    System.exit(0);
}
}

Answer 1

创建服务

public class MyService extends Service implements MediaPlayer.OnPreparedListener {
    private static final String ACTION_PLAY = "com.example.action.PLAY";
    MediaPlayer mMediaPlayer = null;

    public int onStartCommand(Intent intent, int flags, int startId) {
        ...
        if (intent.getAction().equals(ACTION_PLAY)) {
            mMediaPlayer = ... // initialize it here
            mMediaPlayer.setOnPreparedListener(this);
            mMediaPlayer.prepareAsync(); // prepare async to not block main thread
        }
    }

    /** Called when MediaPlayer is ready */
    public void onPrepared(MediaPlayer player) {
        player.start();
    }
}

启动它

startService(new Intent(this, MyService.class));

了解更多here...

Android中的背景音乐连续和强制关闭

1 个答案: