Android - 绑定到服务

Question

嗨:我似乎无法将活动绑定到同一个包中的服务.

活动如下:

public class myApp extends TabActivity {
    static private String TAG = "myApp";
    private myService mService = null;
    private ServiceConnection mServiceConn = new ServiceConnection(){
        public void onServiceConnected(ComponentName name, IBinder service) {
            Log.v(TAG, "Service: " + name + " connected");
            mService = ((myService.myBinder)service).getService();
        }

        public void onServiceDisconnected(ComponentName name) {
            Log.v(TAG, "Service: " + name + " disconnected");
        }
    };

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        doBind();
        Log.i(TAG, "Started (UI Thread)");

        // set content
        setContentView(R.layout.main);

        Resources res = getResources(); // Resource object to get Drawables
        TabHost tabHost = getTabHost();  // The activity TabHost

        ... add some tabs here....

        tabHost.setCurrentTab(0);
    }

    private void doBind(){      
        Intent i = new Intent(this,myService.class);
        if( bindService(i, mServiceConn, 0 )){
            Log.i(TAG, "Service bound");
        } else {
            Log.e(TAG, "Service not bound");
        }
    }

}

然后服务:

public class myService extends Service {
    private String TAG = "myService";

    private boolean mRunning = false;

    @Override
    public int onStartCommand(Intent intent, int flags, int startid) {
        Log.i(TAG,"Service start");

        mRunning = true;

        Log.d(TAG,"Finished onStartCommand");
        return START_STICKY;
    }

    /*
     * Called on service stop
     */
    @Override
    public void onDestroy(){
        Log.i(TAG,"onDestroy");
        mRunning = false;
        super.onDestroy();
    }

    @Override
    public IBinder onBind(Intent intent) {
        return mBinder;
    }


    boolean isRunning() {
        return mRunning;
    }

    /*
     * class for binding
     */
    private final IBinder mBinder = new myBinder();
    public class myBinder extends Binder {
        myService getService() {
            return myService.this;
        }
    }
}

bindService返回true,但永远不会调用onServiceConnection(mService总是为null,所以我不能做像mService.isRunning()这样的事情)

该服务的清单条目只是:

<service android:name=".myService"></service>

我是直接从Android开发者网站复制代码,但我一定错过了一些东西.

Answer 1

这是一个已知的问题,即活动开始时作为tabactivity中的子活动(在tabhost中运行)无法绑定到服务,即使在同一个包中也是如此.有一个"黑客"的解决方法.如果你打电话:

 getApplicationContext().bindService(Intent, connection, flags);

而不仅仅是:

 bindService(Intent, connection, flags);

一切都会奏效.遇到同样的问题,在这个错误报告中找到了详细信息:http: //code.google.com/p/android/issues/detail？id = 2483