我正在实现Service
,它与服务器建立TCP连接,然后允许客户端通过此连接传递消息。客户端通过bindService
呼叫连接到服务。结果,在客户端onServiceConnected
对象中调用了ServiceConnection
。问题是onServiceConnected
从bindService
返回后立即被调用,但是此时我的Service
尚未与服务器建立连接。无法建立连接时可以以某种方式延迟onServiceConnected
通话吗?如果不可能,请针对我的情况提出一些好的模式。谢谢。
最佳答案
您应该按照以下步骤进行操作:
服务代码:
class MyService implements Service {
private boolean mIsConnectionEstablished = false;
// Binder given to clients
private final IBinder mBinder = new LocalBinder();
public class LocalBinder extends Binder {
public MyService getService() {
// Return this instance of LocalService so clients can call public
// methods
return MyService.this;
}
}
public interface OnConnectionEstablishedListener {
public void onConnectionEstablished();
}
private OnConnectionEstablishedListener mListener;
@Override
public void onCreate() {
super.onCreate();
new Thread( new Runnable() {
@Override
void run() {
//Connect to the server here
notifyConnectionEstablished();
}
}).start();
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
private void notifyConnectionEstablished() {
mIsConnectionEstablished = true;
if(mListener != null) {
mListener.onConnectionEstablished();
}
}
public void setOnConnectionEstablishedListener(
OnConnectionEstablishedListener listener) {
mListener = listener
// Already connected to server. Notify immediately.
if(mIsConnectionEstablished) {
mListener.onConnectionEstablished();
}
}
}
活动代码:
class MyActivity extends Activity implements ServiceConnection,
OnConnectionEstablishedListener {
private MyService mService;
private boolean mBound;
@Override
public void onCreate() {
super.onCreate();
//bind the service here
Intent intent = new Intent(this, MyService.class);
bindService(intent, this, BIND_AUTO_CREATE);
}
@Override
public void onServiceConnected(ComponentName className, IBinder service) {
LocalBinder binder = (LocalBinder) service;
mService = binder.getService();
mBound = true;
mService.setOnConnectionEstablishedListener(this);
}
@Override
public void onServiceDisconnected(ComponentName arg0) {
mBound = false;
}
@Override
public void onConnectionEstablished() {
// At this point the service has been bound and connected to the server
// Do stuff here
// Note: This method is called from a non-UI thread.
}
}