android service组件学习-1

这里使用播放器播放音乐来做例子.直接上代码：

package org.example.service;import java.io.IOException;import android.app.Service;import android.content.Intent;import android.media.MediaPlayer;import android.net.Uri;import android.os.Bundle;import android.os.IBinder;import android.util.Log;public class MServices extends Service {//使用该类来播放音乐private MediaPlayer player;/** * DOC 该方法在生命周期中只会调用一次 */@Overridepublic void onCreate() {if (player == null) {//实例化播放器player=new MediaPlayer();try {//设置指向的歌曲player.setDataSource("/sdcard/1.mp3");player.prepare();} catch (Exception e) {e.printStackTrace();}}super.onCreate();}/** * DOC 该方法在生命周期中会被多次掉的用 * （使用activity.startService()方法） */@Overridepublic int onStartCommand(Intent intent, int flags, int startId) {Bundle extras = intent.getExtras();if (extras != null) {//根据不同的请求来处理动作int data = extras.getInt("data");switch (data) {case 1:play();break;case 2:pause();break;case 3:stop();break;default:break;}}return super.onStartCommand(intent, flags, startId);}private void stop() {if (player != null) {System.out.println("stop");player.stop();try {player.prepare();} catch (IllegalStateException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}}private void pause() {if (player != null && player.isPlaying()) {System.out.println("pause");player.pause();}}private void play() {if (player != null && !player.isPlaying()) {System.out.println("play");player.start();}}@Overridepublic void onDestroy() {if (player != null) {player.stop();player.release();}super.onDestroy();}@Overridepublic IBinder onBind(Intent arg0) {return null;}}

package org.example.service;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class ServicesActivity extends Activity implements OnClickListener {private Button play, pause, stop, close, exit;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);play = (Button) findViewById(R.id.play);pause = (Button) findViewById(R.id.pause);stop = (Button) findViewById(R.id.stop);close = (Button) findViewById(R.id.close);exit = (Button) findViewById(R.id.exit);play.setOnClickListener(this);pause.setOnClickListener(this);stop.setOnClickListener(this);close.setOnClickListener(this);exit.setOnClickListener(this);}@Overridepublic void onClick(View v) {//启用serviceIntent intent = new Intent(this, MServices.class);int i = 0;if (v.getId() == play.getId()) {i = 1;} else if (v.getId() == pause.getId()) {i = 2;} else if (v.getId() == stop.getId()) {i = 3;} else if (v.getId() == close.getId()) {stopService(intent);} else if (v.getId() == exit.getId()) {this.finish();}if (i != 0) {intent.putExtra("data", i);startService(intent);}}}

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical" >    <Button        android:id="@+id/play"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="play" />    <Button        android:id="@+id/pause"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="pause" />    <Button        android:id="@+id/stop"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="stop" />    <Button        android:id="@+id/close"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="close" />    <Button        android:id="@+id/exit"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="exit" /></LinearLayout>

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="org.example.service"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk android:minSdkVersion="10" />    <application        android:icon="@drawable/ic_launcher"        android:label="@string/app_name" >        <activity            android:label="@string/app_name"            android:name=".ServicesActivity" >            <intent-filter >                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>        <service android:name=".MServices"></service>    </application></manifest>