安卓Android广播线程服务与多媒体开发实验报告

.实 验 报 告（2013/2014学年 第一学期）课程名称软件技术系列课程（Android基础）实验名称Android广播、线程、服务与多媒体开发实验时间2013年12月9日指导单位计算机学院、诚迈科技（南京）公司指导教师学生姓名班级学号学院(系)计算机学院专 业软件工程(计算机软件与服务外包)成 绩批阅人王彦日期2013-12-09精品.精品.实 验 报 告实验名称Android广播、线程、服务与多媒体开发指导教师实验类型实验实验学时4实验时间2013-12-9一、 实验目的和要求验证Broadcast的发送与接收验证多线程间的数据传递验证Service的使用方法验证多媒体开发中音频、视频、或图像的采集与播放编写一个Android小程序要求：1、使用广播传递数据或信息2、使用多线程3、适当应用Service4、实现至少一种多媒体功能 二、 实验环境(实验设备) PC(Window7)、Eclipse精品.三、 实验原理及内容在这个程序中涉及到了Receiver和BroadcastReceiver的结合使用，首先在AndroidManifest.xml中注册Receiver，实现能够在后台播放音乐的功能。 通过CommandReceiver类实现接受前台Activity发送的播放命令的Intent。在CommandReceiver类中，有后台Service注册的接受前台控制命令Intent的Receiver，广播播放状态变化的Intent代码public class MusicService extends Service implements Runnable private MediaPlayer player;private List lists;public static int _id = 1; / 当前播放位置public static Boolean isRun = true;public LrcProcess mLrcProcess;public LrcView mLrcView;public static int playing_id = 0;public static Boolean playing = false;Overridepublic IBinder onBind(Intent arg0) / TODO Auto-generated method stubreturn null;Overridepublic void onCreate() / TODO Auto-generated method stublists = MusicList.getMusicData(getApplicationContext();SeekBarBroadcastReceiver receiver = new SeekBarBroadcastReceiver();IntentFilter filter = new IntentFilter(.karl.seekBar);this.registerReceiver(receiver, filter);new Thread(this).start();super.onCreate();Overridepublic void onStart(Intent intent, int startId) 精品./ TODO Auto-generated method stubString play = intent.getStringExtra(play);_id = intent.getIntExtra(id, 1);if (play.equals(play) if (null != player) player.release();player = null;playMusic(_id); else if (play.equals(pause) if (null != player) player.pause(); else if (play.equals(playing) if (player != null) player.start(); else playMusic(_id); else if (play.equals(replaying) else if (play.equals(first) int id = intent.getIntExtra(id, 0);playMusic(id); else if (play.equals(rewind) int id = intent.getIntExtra(id, 0);playMusic(id); else if (play.equals(forward) int id = intent.getIntExtra(id, 0);playMusic(id); else if (play.equals(last) int id = intent.getIntExtra(id, 0);playMusic(id);private void playMusic(int id) / / 初始化歌词配置 / /mLrcProcess = new LrcProcess();/ 读取歌词文件精品.mLrcProcess.readLRC(lists.get(_id).getUrl();/ 传回处理后的歌词文件lrcList = mLrcProcess.getLrcContent();MusicActivity.lrc_view.setSentenceEntities(lrcList);/ 切换带动画显示歌词MusicActivity.lrc_view.setAnimation(AnimationUtils.loadAnimation(MusicService.this, R.anim.alpha_z);/ 启动线程mHandler.post(mRunnable);/ / 初始化歌词配置 / /if (null != player) player.release();player = null;if (id = lists.size() - 1) _id = lists.size() - 1; else if (id = 0) _id = 0;Music m = lists.get(_id);String url = m.getUrl();Uri myUri = Uri.parse(url);player = new MediaPlayer();player.reset();player.setAudioStreamType(AudioManager.STREAM_MUSIC);try player.setDataSource(getApplicationContext(), myUri);player.prepare(); catch (IllegalArgumentException e) / TODO Auto-generated catch blocke.printStackTrace(); catch (SecurityException e) / TODO Auto-generated catch blocke.printStackTrace(); catch (IllegalStateException e) / TODO Auto-generated catch blocke.printStackTrace(); catch (IOException e) / TODO Auto-generated catch blocke.printStackTrace();player.start();精品.player.setOnCompletionListener(new OnCompletionListener() Overridepublic void onCompletion(MediaPlayer mp) / TODO Auto-generated method stub/ 下一首if (MusicActivity.isLoop = true) player.reset();Intent intent = new Intent(pletion);sendBroadcast(intent);_id = _id + 1;playMusic(_id); else / 单曲播放player.reset();Intent intent = new Intent(pletion);sendBroadcast(intent);playMusic(_id););player.setOnErrorListener(new OnErrorListener() Overridepublic boolean onError(MediaPlayer mp, int what, int extra) / TODO Auto-generated method stubif (null != player) player.release();player = null;Music m = lists.get(_id);String url = m.getUrl();Uri myUri = Uri.parse(url);player = new MediaPlayer();player.reset();player.setAudioStreamType(AudioManager.STREAM_MUSIC);try player.setDataSource(getApplicationContext(), myUri);player.prepare(); catch (IllegalArgumentException e) / TODO Auto-generated catch blocke.printStackTrace(); catch (SecurityException e) / TODO Auto-generated catch blocke.printStackTrace();精品. catch (IllegalStateException e) / TODO Auto-generated catch blocke.printStackTrace(); catch (IOException e) / TODO Auto-generated catch blocke.printStackTrace();player.start();return false;);private class SeekBarBroadcastReceiver extends BroadcastReceiver Overridepublic void onReceive(Context context, Intent intent) / TODO Auto-generated method stubint seekBarPosition = intent.getIntExtra(seekBarPosition, 0);/ System.out.println(-+seekBarPosition);player.seekTo(seekBarPosition * player.getDuration() / 100);player.start();Overridepublic void run() / TODO Auto-generated method stubwhile (isRun) try Thread.sleep(200); catch (InterruptedException e) / TODO Auto-generated catch blocke.printStackTrace();if (null != player) int position = player.getCurrentPosition();int total = player.getDuration();Intent intent = new Intent(.karl.progress);intent.putExtra(position, position);intent.putExtra(total, total);精品.sendBroadcast(intent);if (null != player) if (player.isPlaying() playing = true; else playing = false;Handler mHandler = new Handler();/ 歌词滚动线程Runnable mRunnable = new Runnable() Overridepublic void run() / TODO Auto-generated method stubMusicActivity.lrc_view.SetIndex(LrcIndex();MusicActivity.lrc_view.invalidate();mHandler.postDelayed(mRunnable, 100);/ 创建对象private List lrcList = new ArrayList();/ 初始化歌词检索值private int index = 0;/ 初始化歌曲播放时间的变量private int CurrentTime = 0;/ 初始化歌曲总时间的变量private int CountTime = 0;/* * 歌词同步处理类 */public int LrcIndex() if (player.isPlaying() / 获得歌曲播放在哪的时间CurrentTime = player.getCurrentPosition();/ 获得歌曲总时间长度CountTime = player.getDuration();精品.if (CurrentTime CountTime) for (int i = 0; i lrcList.size(); i+) if (i lrcList.size() - 1) if (CurrentTime lrcList.get(i).getLrc_time()& CurrentTime lrcList.get(i).getLrc_time() index = i;return index;精品.四、 实验小结（包括问题和解决方法、心得体会等） 1.对于sendBroadCast的intent对象，需要设置其actionname；2.推荐使用显式指明receiver，在配置文件AndroidManifest.xml指明；3.一个receiver可以接收多个action; 4.每次接收广播都会重新生成一个接收广播的对象，再次调用onReceive； 5.在BroadCast中尽量不要处理太多逻辑问题，建议复杂的逻辑交给Activity或者Service去处理。通过这次实验，让我对Broadcast、尤其是Service有了更深入的认识，还让我意识到编程方面和知识体系机构方面存在的不足 。总之，这次试验让我Android编程能力有了一定的提高。利用这次试验，也将我们的大作业更加完善。如有侵权请联系告知删除，感谢你们的配合！精品