学习hellogv写的:MediaPlayer播放网络视频 后添加自己理解的注释!

 

 

package com.lee.video; import java.io.IOException; import java.util.Timer; import java.util.TimerTask; import android.media.AudioManager; import android.media.MediaPlayer; import android.media.MediaPlayer.OnBufferingUpdateListener; import android.media.MediaPlayer.OnCompletionListener; import android.os.Handler; import android.os.Message; import android.util.Log; import android.view.SurfaceHolder; import android.view.SurfaceView; import android.widget.SeekBar; public class Player implements OnBufferingUpdateListener,OnCompletionListener, MediaPlayer.OnPreparedListener,SurfaceHolder.Callback{ private int videoWidth; private int videoHeight; public MediaPlayer mediaPlayer; private SurfaceHolder surfaceHolder; private SeekBar skbProgress; private Timer mTimer=new Timer(); //時間任務,有獨立線程的run() TimerTask mTimerTask = new TimerTask() { @Override public void run() { if(mediaPlayer==null) return; if (mediaPlayer.isPlaying() && skbProgress.isPressed() == false) { // 執行任務,通知handleProgress handleProgress.sendEmptyMessage(0); } } }; // 監聽TimerTask發出的通知信息 Handler handleProgress = new Handler() { // 當有信息傳入,就會執行執行任務 public void handleMessage(Message msg) { int position = mediaPlayer.getCurrentPosition(); int duration = mediaPlayer.getDuration(); if (duration > 0) { // 改變進度條遊標的位置 long pos = skbProgress.getMax() * position / duration; skbProgress.setProgress((int) pos); } }; }; public Player(SurfaceView surfaceView,SeekBar skbProgress){ this.skbProgress=skbProgress; //通過主程序AndroidVideoPlayer實例化一個SurfaceHolder this.surfaceHolder=surfaceView.getHolder(); //增加一個callback監聽器 surfaceHolder.addCallback(this); surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); // 設置時間表(第一次執行任務是從0秒開始,之後每隔一秒執行一次) mTimer.schedule(mTimerTask, 0, 1000); } // 開始運行MediaPlayer public void play(){ mediaPlayer.start(); } // 運行網絡資源 public void playUrl(String url){ try { mediaPlayer.reset(); mediaPlayer.setDataSource(url); mediaPlayer.prepare(); } catch (IllegalArgumentException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalStateException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } // 暫停播放 public void pause() { mediaPlayer.pause(); } // 停止播放 public void stop() { if (mediaPlayer != null) { mediaPlayer.stop(); mediaPlayer.release(); mediaPlayer = null; } } public void onBufferingUpdate(MediaPlayer arg0, int bufferingProgress) { // TODO Auto-generated method stub // 獲得已緩衝的進度 skbProgress.setSecondaryProgress(bufferingProgress); // 遊標的進度 int currentProgress=skbProgress.getMax()*mediaPlayer.getCurrentPosition()/mediaPlayer.getDuration(); Log.e(currentProgress+"% play", bufferingProgress + "% buffer"); } public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) { Log.e("mediaPlayer", "surface changed"); } public void surfaceCreated(SurfaceHolder arg0) { try { // 首先我們需要構建一個MediaPlayer mediaPlayer = new MediaPlayer(); mediaPlayer.setDisplay(surfaceHolder); mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC); mediaPlayer.setOnBufferingUpdateListener(this); mediaPlayer.setOnPreparedListener(this); } catch (Exception e) { Log.e("mediaPlayer", "error", e); } Log.e("mediaPlayer", "surface created"); } public void surfaceDestroyed(SurfaceHolder arg0) { // TODO Auto-generated method stub } public void onPrepared(MediaPlayer mp) { // TODO Auto-generated method stub videoWidth = mediaPlayer.getVideoWidth(); videoHeight = mediaPlayer.getVideoHeight(); // 準備完成的標誌是視頻的尺寸不為零 if (videoHeight != 0 && videoWidth != 0) { mp.start(); } Log.e("mediaPlayer", "onPrepared"); } public void onCompletion(MediaPlayer mp) { // TODO Auto-generated method stub } }