利用Service制作音乐播放器.doc

利用Service制作音乐播放器的步骤：（1）新建工程music，包名：com.music，Activity的名字：MusicActivity。（2） 在res/layout/main.xml中写入如下代码： （3） 放入音乐资源。在res下新建文件夹raw,在该文件夹中发如音乐文件：如：poker_face.mp3注意：a.若新建文件夹名字不为raw，会出错 b音乐文件的名字必须是:az09_.组成，不能有大写字母。（4） 编写MusicActivity,源代码为：package com.music;import android.app.Activity;import android.content.ComponentName;import android.content.Context;import android.content.Intent;import android.content.ServiceConnection;import android.os.Bundle;import android.os.IBinder;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.Toast;public class MusicActivity extends Activity /为日志工具设置标签 private static String TAG = MusicService; /* Called when the activity is first created. */ Override public void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.main); /输出Toast消息和日志记录 Toast.makeText(this, MusicServiceActivity, Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicServiceActivity); initlizeViews(); private void initlizeViews() Log.e(initlizeviews, 初始化界面); Button btnStart = (Button)findViewById(R.id.startMusic); Button btnStop = (Button)findViewById(R.id.stopMusic); Button btnBind = (Button)findViewById(R.id.bindMusic); Button btnUnbind = (Button)findViewById(R.id.unbindMusic); Log.e(MusicActivity, 获得组件ID号); /定义点击监听器 OnClickListener ocl = new OnClickListener() Override public void onClick(View v) /显示指定 intent所指的对象是个 service Log.e(MusicActivity, 点击了启动按钮); Intent intent = new Intent(MusicActivity.this,MusicService.class); switch(v.getId() case R.id.startMusic: /开始服务 Log.e(MusicActivity, 即将启动服务); startService(intent); Log.e(MusicActivity, 启动完毕); break; case R.id.stopMusic: /停止服务 Log.e(MusicActivity, 即将停止服务); stopService(intent); Log.e(MusicActivity, 停止完毕); break; case R.id.bindMusic: /绑定服务 Log.e(MusicActivity, 绑定服务); bindService(intent, conn, Context.BIND_AUTO_CREATE); Log.e(MusicActivity, 绑定完毕); break; case R.id.unbindMusic: /解绑服务 Log.e(MusicActivity, 解除绑定服务); unbindService(conn); Log.e(MusicActivity, 解除完毕); break; ; /绑定点击监听 btnStart.setOnClickListener(ocl); btnStop.setOnClickListener(ocl); btnBind.setOnClickListener(ocl); btnUnbind.setOnClickListener(ocl); /定义服务链接对象 final ServiceConnection conn = new ServiceConnection() Override /Toast.LENGTH_SHORT大概显示时间为1秒， / Toast.LENGTH_LONG大概显示时间为3秒 public void onServiceDisconnected(ComponentName name) Toast.makeText(MusicActivity.this, MusicActivity onSeviceDisconnected , Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicActivity onSeviceDisconnected); Override public void onServiceConnected(ComponentName name, IBinder service) Toast.makeText(MusicActivity.this, MusicServiceActivity onServiceConnected ,Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicServiceActivity onServiceConnected); ;（5） 在src的com.music包下新建类，MusicService.java。该文件的源文件为：package com.music;import android.app.Service;import android.content.Intent;import android.media.MediaPlayer;import android.os.IBinder;import android.util.Log;import android.widget.Toast;public class MusicService extends Service /为日志工具设置标签 private static String TAG = MusicService; /定义音乐播放器变量 private MediaPlayer mPlayer; /该服务不存在需要被创建时被调用，不管startService()还是bindService()都会启动时调用该方法 Override public void onCreate() Log.e(MusicService, -onCreate); Toast.makeText(this, MusicSevice onCreate() , Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicSerice onCreate(); mPlayer = MediaPlayer.create(getApplicationContext(), R.raw.poker_face); if(mPlayer=null) Log.e(mPlayer, -null); else Log.e(mPlayer, -not null); /设置可以重复播放 mPlayer.setLooping(true); Log.e(mPlayer, -setLooping); super.onCreate(); Override public void onStart(Intent intent, int startId) Log.e(MusicService, -onStart); Toast.makeText(this, MusicSevice onStart() , Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicSerice onStart(); mPlayer.start(); super.onStart(intent, startId); Override public void onDestroy() Log.e(MusicService, -onDestroy); Toast.makeText(this, MusicSevice onDestroy() , Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicSerice onDestroy(); mPlayer.stop(); super.onDestroy(); /其他对象通过bindService 方法通知该Service时该方法被调用 Override public IBinder onBind(Intent intent) Log.e(MusicService, -onBind); Toast.makeText(this, MusicSevice onBind() , Toast.LENGTH_SHORT).show(); Log.e(TAG, MusicSerice onBind(); mPlayer.start(); return null; /其它对象通过unbindService方法通知该Service时该方法被调用 Override public boolean onUnbind(Intent intent) Toast.makeText(this, Music