MediaPlayer 用法(一)
使用SurfaceView播放视频,其实很简单,但是经常会碰见有声音没图像的问题.
其实使用SurfaceView播放视频只需要主要下面几个地方就可以了
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1. surfaceChanged也就是Suface是否创建成功
2. onPrepared 也就是MideoPlayer是否加载并准备完成
3. surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
类型必须是SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS
package VideoTest.Test;import java.io.FileDescriptor;import android.app.Activity;import android.content.res.AssetFileDescriptor;import android.media.AudioManager;import android.media.MediaPlayer;import android.media.MediaPlayer.OnBufferingUpdateListener;import android.media.MediaPlayer.OnCompletionListener;import android.media.MediaPlayer.OnPreparedListener;import android.os.Bundle;import android.view.SurfaceHolder;import android.view.SurfaceView;public class VideoTest extends Activity implements SurfaceHolder.Callback, OnBufferingUpdateListener, OnCompletionListener, OnPreparedListener{private SurfaceView surfaceView;private SurfaceHolder surfaceHolder;private MediaPlayer mediaPlayer;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);this.surfaceView = new SurfaceView(this);this.surfaceHolder = this.surfaceView.getHolder();this.surfaceHolder.addCallback(this);//类型必须设置成SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERSthis.surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);setContentView(this.surfaceView);}@Overridepublic void onDestroy() {super.onDestroy();if (this.mediaPlayer != null) {this.mediaPlayer.release();this.mediaPlayer = null;}}public void PlayVideo(){try {//视频文件放在 assert中AssetFileDescriptor aFD = this.getAssets().openFd("welcome.3gp");FileDescriptor fileDescriptor = aFD.getFileDescriptor();this.mediaPlayer = new MediaPlayer();this.mediaPlayer.setDataSource(fileDescriptor, aFD.getStartOffset(), aFD.getLength());aFD.close();//视频放在SDCard中//File sdFile = Environment.getExternalStorageDirectory();//this.mediaPlayer = new MediaPlayer();//this.mediaPlayer.setDataSource(sdFile.getAbsoluteFile() + File.separator + "welcome.3gp");//视频放在res中//this.mediaPlayer = MediaPlayer.create(this, R.raw.welcome);//网上的视频,没有测试//this.mediaPlayer//.setDataSource("http://xy2.163.com/download/down/wukong.mp3");this.mediaPlayer.setDisplay(this.surfaceHolder);this.mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);//准备完成后才可以播放,另外如果文件特别大或者从网上获得的资源//会在这里等待时间过长,造成堵塞,这样的话就得用//this.mediaPlayer.prepareAsync(),然后监听是否准备完毕在开始this.mediaPlayer.prepare();this.mediaPlayer.start();} catch (Exception e) {// TODO: handle exception}}@Overridepublic void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {}@Overridepublic void surfaceCreated(SurfaceHolder holder) {//SurfaceCreated 创建成功才可以播放视频PlayVideo();}@Overridepublic void surfaceDestroyed(SurfaceHolder holder) {}//@Overridepublic void onBufferingUpdate(MediaPlayer mp, int percent) {// TODO Auto-generated method stub}//@Overridepublic void onCompletion(MediaPlayer mp) {// TODO Auto-generated method stub}//@Overridepublic void onPrepared(MediaPlayer mp) {//MediaPlayer加载准备完毕才能开始播放//mp.start();}}??
但是,对于一些人可能会产生另一个问题就是
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
在设置成SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS类型后,无法画图了
SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS的意思是创建一个"PUSH"surface,这个surface没有自己的缓冲区,没有自己的缓冲Buffer.
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1 楼 lattimore 2010-10-21 这个时候视频播放，视频绘制操作完全交给MediaPlayer的底层去做了。