Android提高之MediaPlayer播放网络视频

本文来自http://blog.csdn.net/hellogv/ ，引用必须注明出处！

       上次讲解了MediaPlayer播放网络音频，介绍了MediaPlayer关于网络音频的缓冲和进度条控制的方法，这次再讲解MediaPlayer播放网络视频。播放网络视频比播放网络音频多需要一个SurfaceView而已，已经熟悉MediaPlayer播放网络音频之后，相信大家对播放网络视频也能很快地掌握。先来看看本文程序运行截图：

本文程序的视频来自http://daily3gp.com，大家可以替换程序中的视频链接，试试其他影片。

main.xml的源码如下：

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="fill_parent" android:layout_width="fill_parent">
    <SurfaceView android:id="@+id/surfaceView1"
        android:layout_height="fill_parent" android:layout_width="fill_parent"></SurfaceView>
    <LinearLayout android:layout_height="wrap_content"
        android:layout_width="fill_parent" android:layout_gravity="bottom"
        android:orientation="vertical">
        <LinearLayout android:orientation="horizontal"
            android:layout_gravity="center_horizontal" android:layout_marginTop="4.0dip"
            android:layout_height="wrap_content" android:layout_width="wrap_content">
            <Button android:layout_width="wrap_content"
                android:layout_height="wrap_content" android:id="@+id/btnPlayUrl"
                android:text="播放网络视频"></Button>
            <Button android:layout_height="wrap_content" android:id="@+id/btnPause"
                android:text="暂停" android:layout_width="80dip"></Button>
            <Button android:layout_height="wrap_content"
                android:layout_width="80dip" android:text="停止" android:id="@+id/btnStop"></Button>
        </LinearLayout>
        <LinearLayout android:orientation="horizontal"
            android:layout_width="fill_parent" android:layout_height="wrap_content"
            android:layout_marginBottom="20dip">
            <SeekBar android:paddingRight="10dip" android:layout_gravity="center_vertical"
                android:paddingLeft="10dip" android:layout_weight="1.0"
                android:layout_height="wrap_content" android:layout_width="wrap_content"
                android:id="@+id/skbProgress" android:max="100"></SeekBar>
        </LinearLayout>
    </LinearLayout>
</FrameLayout>

Player.java是本文的核心，Player.java实现了“进度条更新”、“数据缓冲”、“SurfaceHolder生命周期”等功能，其中“SurfaceHolder生命周期”是视频与音频播放的最大区别，通过surfaceCreated()、surfaceDestroyed()、surfaceChanged()可以创建/释放某些资源。下面这个地方需要注意一下：

videoWidth = mediaPlayer.getVideoWidth();
        videoHeight = mediaPlayer.getVideoHeight();
        if (videoHeight != 0 && videoWidth != 0) {
            arg0.start();
        }

有些视频是android播放器不能播放的，不能播放时videoHeight=0，videoWidth=0，以此来判断是否播放视频。

Player.java源码如下：

package com.videoplayer;


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();
    public Player(SurfaceView surfaceView,SeekBar skbProgress)
    {
        this.skbProgress=skbProgress;
        surfaceHolder=surfaceView.getHolder();
        surfaceHolder.addCallback(this);
        surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        mTimer.schedule(mTimerTask, 0, 1000);
    }

    /*******************************************************
     * 通过定时器和Handler来更新进度条
     ******************************************************/
    TimerTask mTimerTask = new TimerTask() {
        @Override
        public void run() {
            if(mediaPlayer==null)
                return;
            if (mediaPlayer.isPlaying() && skbProgress.isPressed() == false) {
                handleProgress.sendEmptyMessage(0);
            }
        }
    };

    Handler handleProgress = new Handler() {
        public void handleMessage(Message msg) {

            int position = mediaPlayer.getCurrentPosition();
            int duration = mediaPlayer.getDuration();

            if (duration > 0) {
                long pos = skbProgress.getMax() * position / duration;
                skbProgress.setProgress((int) pos);
            }
        };
    };
    //*****************************************************

    public void play()
    {
        mediaPlayer.start();
    }

    public void playUrl(String videoUrl)
    {
        try {
            mediaPlayer.reset();
            mediaPlayer.setDataSource(videoUrl);
            mediaPlayer.prepare();//prepare之后自动播放
            //mediaPlayer.start();
        } 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();
        }
    }


    public void pause()
    {
        mediaPlayer.pause();
    }

    public void stop()
    {
        if (mediaPlayer != null) {
            mediaPlayer.stop();
            mediaPlayer.release();
            mediaPlayer = null;
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
        Log.e("mediaPlayer", "surface changed");
    }

    @Override
    public void surfaceCreated(SurfaceHolder arg0) {
        try {
            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");
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder arg0) {
        Log.e("mediaPlayer", "surface destroyed");
    }


    @Override
    /**
     * 通过onPrepared播放
     */
    public void onPrepared(MediaPlayer arg0) {
        videoWidth = mediaPlayer.getVideoWidth();
        videoHeight = mediaPlayer.getVideoHeight();
        if (videoHeight != 0 && videoWidth != 0) {
            arg0.start();
        }
        Log.e("mediaPlayer", "onPrepared");
    }

    @Override
    public void onCompletion(MediaPlayer arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onBufferingUpdate(MediaPlayer arg0, int bufferingProgress) {
        skbProgress.setSecondaryProgress(bufferingProgress);
        int currentProgress=skbProgress.getMax()*mediaPlayer.getCurrentPosition()/mediaPlayer.getDuration();
        Log.e(currentProgress+"% play", bufferingProgress + "% buffer");

    }

}

 

test_videoplayer.java是主程序，负责调用Player类，其中关键部分是SeekBarChangeEvent这个SeekBar拖动的事件：SeekBar的Progress是0~SeekBar.getMax()之内的数，而MediaPlayer.seekTo()的参数是0~MediaPlayer.getDuration()之内数，所以MediaPlayer.seekTo()的参数是(progress/seekBar.getMax())*MediaPlayer.getDuration()。

 

test_videoplayer.java源码如下：

 

package com.videoplayer;

import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.SeekBar;

public class test_videoplayer extends Activity {
    private SurfaceView surfaceView;
    private Button btnPause, btnPlayUrl, btnStop;
    private SeekBar skbProgress;
    private Player player;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView1);

        btnPlayUrl = (Button) this.findViewById(R.id.btnPlayUrl);
        btnPlayUrl.setOnClickListener(new ClickEvent());

        btnPause = (Button) this.findViewById(R.id.btnPause);
        btnPause.setOnClickListener(new ClickEvent());

        btnStop = (Button) this.findViewById(R.id.btnStop);
        btnStop.setOnClickListener(new ClickEvent());

        skbProgress = (SeekBar) this.findViewById(R.id.skbProgress);
        skbProgress.setOnSeekBarChangeListener(new SeekBarChangeEvent());
        player = new Player(surfaceView, skbProgress);

    }

    class ClickEvent implements OnClickListener {

        @Override
        public void onClick(View arg0) {
            if (arg0 == btnPause) {
                player.pause();
            } else if (arg0 == btnPlayUrl) {
                String url="http://daily3gp.com/vids/family_guy_penis_car.3gp";
                player.playUrl(url);
            } else if (arg0 == btnStop) {
                player.stop();
            }

        }
    }

    class SeekBarChangeEvent implements SeekBar.OnSeekBarChangeListener {
        int progress;

        @Override
        public void onProgressChanged(SeekBar seekBar, int progress,
                boolean fromUser) {
            // 原本是(progress/seekBar.getMax())*player.mediaPlayer.getDuration()
            this.progress = progress * player.mediaPlayer.getDuration()
                    / seekBar.getMax();
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {

        }

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {
            // seekTo()的参数是相对与影片时间的数字，而不是与seekBar.getMax()相对的数字
            player.mediaPlayer.seekTo(progress);
        }
    }

}