将服务从一个 Activity 传递给另一个

Question

如何将服务从一个 activity 传递到另一个？我有一个显示歌曲列表的音乐播放器 (Activity1)，当您单击它时，它会启动 Activity1 中的服务。我有一个按钮，用户可以单击它来打开 Activity2。

那么我将服务从 Activity1 传递到 Activity2 的最佳方式是什么。如果服务在Activity1中启动，那么Activity2应该继续播放。如果Activity1中没有启动该服务，那么Activity2应该先启动该服务才能使用。

谢谢。

这是一些示例代码，MusicService 是一个 class 扩展服务 class。

 public class Activity1 extends AppCompatActivity {

 private MusicService serviceMusic;  

private ServiceConnection musicConnection = new ServiceConnection() {
    @Override
    public void onServiceConnected(ComponentName name, IBinder service) {
        MusicService.PlayerBinder binder = (MusicService.PlayerBinder) service;
        //get service
        serviceMusic = binder.getService();
        serviceMusic.setSongList(songList);
    }

    @Override
    public void onServiceDisconnected(ComponentName name) {

    }
};

}

Answer 1

您可以定义应用程序扩展 class 并在此 class 中使用 public 静态变量并在所有 activity 中访问此变量。

像这样：

public class G extends Aplication{
   public static MusicService serviceMusic;  
}

并在清单中：

  <application ...
    android:name=".G">

现在您可以在任何地方访问 G.serviceMusic。

Answer 2

我认为 bind 服务比 pass a static global 更好服务。由于您有多个活动将使用相同的服务，因此应该像这样创建一个基础 activity：

BasicServiceActivity.java

public abstract class BasicServiceActivity extends AppCompatActivity {
    protected DvrService mDvrService;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_basic);
        attachService();
    }

    @Override
    protected void onDestroy() {
        detachService();
        super.onDestroy();
    }

    private ServiceConnection mServiceConnection = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder binder) {
            DvrService.DvrServiceBinder serviceBinder = (DvrService.DvrServiceBinder) binder;
            mDvrService = serviceBinder.getService();
            onServiceAttached(mDvrService);
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            mDvrService = null;
        }
    };

    private void attachService() {
        Intent service = new Intent(this, DvrService.class);
        bindService(service, mServiceConnection, Service.BIND_AUTO_CREATE);
    }

    private void detachService() {
        unbindService(mServiceConnection);
    }

    /** Callback when service attached. */
    protected void onServiceAttached(DvrService service) {
        // do something necessary by its subclass.
    }
}

然后你可以像这样实现子类activity：

public class ServiceActivity extends BasicServiceActivity {
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        startService(new Intent(this, DvrService.class));
    }

    @Override
    protected void onDestroy() {
        if (mDvrService != null) {
            mDvrService.removeListener1(mListener1);
        }
        super.onDestroy();
    }

    @Override
    protected void onServiceAttached(DvrService service) {
        // do your stuff, for example add a listener.
        service.addListener1(mListener1);
    }
}

将服务从一个 Activity 传递给另一个

Pass Service From one Activity to Another

android

android-service

android-activity

android-service-binding