Service学习

新建一个用于service的class，Superclass属性设置为Service-android.app, 命名为Pservice在其中复写方法，代码如下：

@Override
    public void onCreate() {
        // TODO Auto-generated method stub
        Log.i(TAG, "EXampleService--->onCreate");
        super.onCreate();
    }

    @Override
    public void onDestroy() {
        // TODO Auto-generated method stub
        Log.i(TAG, "EXampleService--->onDestroy");
        super.onDestroy();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // TODO Auto-generated method stub
        Log.i(TAG, "EXampleService--->onStartCommand");
        return super.onStartCommand(intent, flags, startId);
    }

在MainActivity.java中通过write如下监听器来测试service：

    private OnClickListener listener = new OnClickListener() {
        public void onClick(View v) {
            Intent intent = new Intent(MainActivity.this,Pservice.class);
            switch(v.getId()) {
                case R.id.btnStartService: startService(intent); break;
                case R.id.btnStopService:  stopService(intent); break;
                default:                   break;
            }
        }
    };

但需要在Manifest中加入：<service android:name=".Pservice"></service>　这行代码与Activity同级。

Binder service:

Binder service:允许其他组件(如Activity)绑定到这个service上，可以发送请求，也可以接受请求，甚至可以进行进程间的通话。Binder service仅仅在服务于其他组件时存在，不能独自无限期的在后台运行。

创建一个servide类在里面复写onBind,代码如下：

public class BoundService extends Service {
    
    private static final String TAG = "BoundService";
    private MyBinder binder = new MyBinder();
    
    private class MyBinder extends Binder {
        public BoundService getService() {
            return BoundService.this;
        }
    }
    @Override
    public IBinder onBind(Intent arg0) {
        // TODO Auto-generated method stub
        return binder;
    }
    
    public void MyMethod() {
        Log.i(TAG, "MyMethod()");
    }
}

创建一个BinderActivity扩展自Activity，代码如下：

package com.example.pmusicplayer;

import android.os.Bundle;
import android.os.IBinder;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class BinderActivity extends Activity {
    
    private Button btnStartBinderService;
    private Button btnStopBinderService;
    private boolean isConnected = false;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.binder);
        
        btnStartBinderService = (Button)findViewById(R.id.btnStartBinderService);
        btnStopBinderService = (Button)findViewById(R.id.btnStopBinderService);
        btnStartBinderService.setOnClickListener(listener);
        btnStopBinderService.setOnClickListener(listener);
    }
    
    private OnClickListener listener = new OnClickListener() {
        public void onClick(View v) {
            switch(v.getId()) {
                case R.id.btnStartBinderService: bindService(); break;
                case R.id.btnStopBinderService:  unBind(); break;
                default:                   break;
            }
        }
    };
    
    private void unBind() {
        if(isConnected) {
            unbindService(conn);
        }
    }
    
    private void bindService() {
        Intent intent = new Intent(BinderActivity.this, BoundService.class);
        bindService(intent, conn, Context.BIND_AUTO_CREATE);
    }
    
    private ServiceConnection conn = new ServiceConnection() {
        @Override
        public void onServiceDisconnected(ComponentName name) {
            // TODO Auto-generated method stub
            isConnected = false;
        }
        
        @Override
        public void onServiceConnected(ComponentName name, IBinder binder) {
            // TODO Auto-generated method stub
            BoundService service=null;
            service.MyMethod();
            isConnected = true;
        }
    };
    
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.binder, menu);
        return true;
    }

}