Android 跨进程通Messenger(简单易懂)

Z时代
2024-01-10
分类：综合

不需要AIDL也不需要复杂的ContentProvider，也不需要SharedPreferences或者共享存储文件！

只需要简单易懂的Messenger，它也称为信使，通过它可以在不同进程中传递message对象，在message中放入我们需要传递的数据你就可以实现跨进程通讯和传递数据。废话不多说，直接上代码。

首先是服务端：


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,你的消息我已经收到,稍后回复你!");
message.setData(bundle);
try {
messenger.send(message);
} catch (RemoteException e) {
e.printStackTrace();
}
super.handleMessage(msg);
}
}

我们在服务端操作了并不多，仅仅是实例化了一个Messenger，并且创建了一个handler用来接收客户端发送过来的消息

接下来看客户端：


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
}
};
}