bindService()：允許其他元件跟它進行通訊，允許多個客戶端繫結到同一個service上，當所有的客戶端都解除繫結後，該service就銷燬了。

1、main.xml包括bindservice和unbindservice2個按鈕，還有模擬的四個按鈕 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >    



    <Button
        android:id="@+id/bind"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="BindService" />

    <Button
        android:id="@+id/play"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="播放" />

    <Button
        android:id="@+id/pause"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="暫停" />

    <Button
        android:id="@+id/next"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="下一首" />

    <Button
        android:id="@+id/pervious"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="上一首" />

    <Button
        android:id="@+id/unbind"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="UnBindService" />

</LinearLayout>
 

2、AndroidMainfest.xml宣告Service 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.huangyi.bindservicedemo"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="17"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <service android:name="com.huangyi.bindservicedemo.BindService"/>
    </application>

</manifest>
 

3、BindService.java裡面定義了bindService生命週期的幾個方法onCreate----->onBind--->onUnbind---->onDestroy，還自定義了一個類MyBinder整合Binder這個類，並在這個類裡面寫一個方法返回BindService類的物件。當然還有模擬播放的幾個方法。

package com.huangyi.bindservicedemo;

import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;

public class BindService extends Service {

	@Override
	public void onCreate() {
		Log.i("info", "BindService--->onCreate()");
		super.onCreate();
	}
	
	
	@Override
	public IBinder onBind(Intent intent) {
		Log.i("info", "BindService--->onBind()");
		return new MyBinder();
	}

	@Override
	public boolean onUnbind(Intent intent) {
		Log.i("info", "BindService--->onUnbind()");
		return super.onUnbind(intent);
	}
	
	@Override
	public void onDestroy() {
		Log.i("info", "BindService--->onDestroy()");
		super.onDestroy();
	}
	
	public class MyBinder extends Binder{
		public BindService getService(){
			return BindService.this;
		}
	}
	
	public void play(){
		Log.i("info", "播放");
	}
	
	public void pause(){
		Log.i("info", "暫停");
	}
	
	public void next(){
		Log.i("info", "下一首");
	}
	
	public void pervious(){
		Log.i("info", "上一首");
	}
}
 

其中定義了ServiceConnection介面的實現物件conn，將傳遞過來的binder物件轉化為BindService的物件。

package com.huangyi.bindservicedemo;

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

public class MainActivity extends Activity implements OnClickListener{

	private Button bind,play,pause,next,pervious,unbind;
	private Intent intent;
	BindService service;
	
	ServiceConnection conn = new ServiceConnection() {
		
		/**
		 * 當啟動源跟Service的連線意外丟失的時候會呼叫這個方法
		 * ，比如Service崩潰了或者被強行殺死了
		 */
		@Override
		public void onServiceDisconnected(ComponentName name) {
			
		}
		
		/**
		 * 當啟動源跟Service成功連線之後將會呼叫這個方法
		 */
		@Override
		public void onServiceConnected(ComponentName name, IBinder binder) {
			service = ((BindService.MyBinder)binder).getService();
		}
	};
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		bind = (Button) findViewById(R.id.bind);
		play = (Button) findViewById(R.id.play);
		pause = (Button) findViewById(R.id.pause);
		next = (Button) findViewById(R.id.next);
		pervious = (Button) findViewById(R.id.pervious);
		unbind = (Button) findViewById(R.id.unbind);
		
		bind.setOnClickListener(this);
		play.setOnClickListener(this);
		pause.setOnClickListener(this);
		next.setOnClickListener(this);
		pervious.setOnClickListener(this);
		unbind.setOnClickListener(this);
	}

	
	@Override
	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.bind:
			intent = new Intent(MainActivity.this, BindService.class);
			bindService(intent, conn, Service.BIND_AUTO_CREATE);
			break;
		case R.id.play:
			service.play();
			break;
		case R.id.pause:
			service.pause();
			break;
		case R.id.next:
			service.next();
			break;
		case R.id.pervious:
			service.pervious();
			break;
		case R.id.unbind	:
			unbindService(conn);
			break;
		}
	}

}

依次從上到下點選按鈕

程式碼地址：http://download.csdn.net/detail/yihuangol/9259295