我的方法：
管理从/到服务/活动发送和接收消息的类：
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.util.Log;
import java.util.ArrayList;
import java.util.List;
public class MessageManager {
public interface IOnHandleMessage{
// Messages
int MSG_HANDSHAKE = 0x1;
void onHandleMessage(Message msg);
}
private static final String LOGCAT = MessageManager.class.getSimpleName();
private Messenger mMsgSender;
private Messenger mMsgReceiver;
private List<Message> mMessages;
public MessageManager(IOnHandleMessage callback, IBinder target){
mMsgReceiver = new Messenger(new MessageHandler(callback, MessageHandler.TYPE_ACTIVITY));
mMsgSender = new Messenger(target);
mMessages = new ArrayList<>();
}
public MessageManager(IOnHandleMessage callback){
mMsgReceiver = new Messenger(new MessageHandler(callback, MessageHandler.TYPE_SERVICE));
mMsgSender = null;
mMessages = new ArrayList<>();
}
/* START Getter & Setter Methods */
public Messenger getMsgSender() {
return mMsgSender;
}
public void setMsgSender(Messenger sender) {
this.mMsgSender = sender;
}
public Messenger getMsgReceiver() {
return mMsgReceiver;
}
public void setMsgReceiver(Messenger receiver) {
this.mMsgReceiver = receiver;
}
public List<Message> getLastMessages() {
return mMessages;
}
public void addMessage(Message message) {
this.mMessages.add(message);
}
/* END Getter & Setter Methods */
/* START Public Methods */
public void sendMessage(int what, int arg1, int arg2, Bundle msgData){
if(mMsgSender != null && mMsgReceiver != null) {
try {
Message msg = Message.obtain(null, what, arg1, arg2);
msg.replyTo = mMsgReceiver;
if(msgData != null){
msg.setData(msgData);
}
mMsgSender.send(msg);
} catch (RemoteException rE) {
onException(rE);
}
}
}
public void sendHandshake(){
if(mMsgSender != null && mMsgReceiver != null){
sendMessage(IOnHandleMessage.MSG_HANDSHAKE, 0, 0, null);
}
}
/* END Public Methods */
/* START Private Methods */
private void onException(Exception e){
Log.e(LOGCAT, e.getMessage());
e.printStackTrace();
}
/* END Private Methods */
/** START Private Classes **/
private class MessageHandler extends Handler {
// Types
final static int TYPE_SERVICE = 0x1;
final static int TYPE_ACTIVITY = 0x2;
private IOnHandleMessage mCallback;
private int mType;
public MessageHandler(IOnHandleMessage callback, int type){
mCallback = callback;
mType = type;
}
@Override
public void handleMessage(Message msg){
addMessage(msg);
switch(msg.what){
case IOnHandleMessage.MSG_HANDSHAKE:
switch(mType){
case TYPE_SERVICE:
setMsgSender(msg.replyTo);
sendHandshake();
break;
case TYPE_ACTIVITY:
Log.v(LOGCAT, "HERE");
break;
}
break;
default:
if(mCallback != null){
mCallback.onHandleMessage(msg);
}
break;
}
}
}
/** END Private Classes **/
}
在活动示例中：
public class activity extends AppCompatActivity
implements ServiceConnection,
MessageManager.IOnHandleMessage {
[....]
private MessageManager mMessenger;
private void initMyMessenger(IBinder iBinder){
mMessenger = new MessageManager(this, iBinder);
mMessenger.sendHandshake();
}
private void bindToService(){
Intent intent = new Intent(this, TagScanService.class);
bindService(intent, mServiceConnection, Context.BIND_AUTO_CREATE);
/* START THE SERVICE IF NEEDED */
}
private void unbindToService(){
/* UNBIND when you want (onDestroy, after operation...)
if(mBound) {
unbindService(mServiceConnection);
mBound = false;
}
}
/* START Override MessageManager.IOnHandleMessage Methods */
@Override
public void onHandleMessage(Message msg) {
switch(msg.what){
case Constants.MSG_SYNC_PROGRESS:
Bundle data = msg.getData();
String text = data.getString(Constants.KEY_MSG_TEXT);
setMessageProgress(text);
break;
case Constants.MSG_START_SYNC:
onStartSync();
break;
case Constants.MSG_END_SYNC:
onEndSync(msg.arg1 == Constants.ARG1_SUCCESS);
mBound = false;
break;
}
}
/* END Override MessageManager.IOnHandleMessage Methods */
/** START Override ServiceConnection Methods **/
private class BLEScanServiceConnection implements ServiceConnection {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
initMyMessenger(iBinder);
mBound = true;
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
mMessenger = null;
mBound = false;
}
}
/** END Override ServiceConnection Methods **/
在服务示例中：
public class Blablabla extends Service
implements MessageManager.IOnHandleMessage {
[...]
private MessageManager mMessenger;
@Nullable
@Override
public IBinder onBind(Intent intent) {
super.onBind(intent);
initMessageManager();
return mMessenger.getMsgReceiver().getBinder();
}
private void initMessageManager(){
mMessenger = new MessageManager(this);
}
/* START Override IOnHandleMessage Methods */
@Override
public void onHandleMessage(Message msg) {
/* Do what you want when u get a message looking the "what" attribute */
}
/* END Override IOnHandleMessage Methods */
从活动/服务发送消息：
mMessenger.sendMessage(what, arg1, arg2, dataBundle);
这是如何工作的：
在您启动或绑定服务的活动上。服务“OnBind”方法将Binder返回给他的MessageManager，在Activity中通过“Service Connection”接口方法实现“OnServiceConnected”你得到这个IBinder并初始化你使用它的MessageManager。在 Activity 初始化他的 MessageManager 之后，MessageHandler 向服务发送和握手，以便它可以设置他的“MessageHandler”发送者（MessageManager 中的“private Messenger mMsgSender;”）。这样做服务知道谁发送他的消息。
您还可以在 MessageManager 中使用 Messenger“发送者”的列表/队列来实现这一点，这样您就可以将多条消息发送到不同的活动/服务，或者您可以在 MessageManager 中使用 Messenger“接收者”的列表/队列，这样您就可以接收多个来自不同活动/服务的消息。
在“MessageManager”实例中，您有一个收到的所有消息的列表。
如您所见，使用此“MessageManager”实例的“Activity's Messenger”和“Service Messenger”之间的连接是自动的，它是通过“OnServiceConnected”方法和使用“Handshake”完成的。
希望这对你有帮助:) 非常感谢！再见：D