只需要簡(jiǎn)單易懂的Messenger，它也稱為信使，通過(guò)它可以在不同進(jìn)程中傳遞message對(duì)象，在message中放入我們需要傳遞的數(shù)據(jù)你就可以實(shí)現(xiàn)跨進(jìn)程通訊和傳遞數(shù)據(jù)。廢話不多說(shuō)，直接上代碼。

首先是服務(wù)端：

public class Ser extends Service{
@Override
public IBinder onBind(Intent intent) {
return messenger.getBinder();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// TODO Auto-generated method stub
Log.i("Service", "onStartCommand()");
return super.onStartCommand(intent, flags, startId);
}
public Messenger messenger = new Messenger(new MyHandler());
public class MyHandler extends Handler{
@Override
public void handleMessage(Message msg) {
Log.i("Ser---TAG", "msg::"+msg.arg1+"want :"+msg.getData().getString("msg"));
Messenger messenger = msg.replyTo;
Message message = Message.obtain(null, 0);
Bundle bundle = new Bundle();
bundle.putString("reply", "嗯,你的消息我已經(jīng)收到,稍后回復(fù)你!");
message.setData(bundle);
try {
messenger.send(message);
} catch (RemoteException e) {
e.printStackTrace();
}
super.handleMessage(msg);
}
}

我們?cè)诜?wù)端操作了并不多，僅僅是實(shí)例化了一個(gè)Messenger，并且創(chuàng)建了一個(gè)handler用來(lái)接收客戶端發(fā)送過(guò)來(lái)的消息

接下來(lái)看客戶端：

public class Client extends Service{
private static final String TAG = "Client";
protected Messenger mService;
public Handler handler = new Handler(){
public void handleMessage(Message msg) {
Log.i("client --- TAG", "msg:;"+msg.getData().getString("reply"));
};
};
public Messenger messenger = new Messenger(handler);
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Intent mIntent = new Intent();
mIntent.setClassName("com.example.test1", "com.example.test1.Ser");
bindService(mIntent, mBindService, Context.BIND_AUTO_CREATE);
return super.onStartCommand(intent, flags, startId);
}
@Override
public void onDestroy() {
super.onDestroy();
unbindService(mBindService);
}
private ServiceConnection mBindService = new ServiceConnection(){
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
mService = new Messenger(service);
Message message = Message.obtain(null, 0);
Bundle bundle = new Bundle();
bundle.putString("msg", "hello this is client!");
message.replyTo = messenger;
message.setData(bundle);
try {
mService.send(message);
} catch (RemoteException e) {
e.printStackTrace();
}
}
@Override
public void onServiceDisconnected(ComponentName name) {
// TODO Auto-generated method stub
}
};
}

同樣客戶端也需要一個(gè)handler來(lái)接收服務(wù)端返回的消息，還有很關(guān)鍵的一點(diǎn)

當(dāng)客戶端發(fā)送消息的時(shí)候，需要把接收服務(wù)端回復(fù)的Messenger通過(guò)Message的

replyTo參數(shù)傳遞給服務(wù)端，否則會(huì)報(bào)NullPointerException。然后我們?cè)诳聪耹og

"hello this is client!" 這是客戶端發(fā)給服務(wù)端的，證明服務(wù)端已經(jīng)收到！

"嗯,你的消息我已經(jīng)收到,稍后回復(fù)你!" 這是服務(wù)端返回給客戶端的，證明客戶端也收到了，并且還是實(shí)時(shí)通訊哦,到此我們的跨進(jìn)程傳遞數(shù)據(jù)通訊完整結(jié)束啦，是不是很簡(jiǎn)單！

您可能感興趣的文章: