Android学习一、MediaPlayer播放音频

想要使用MediaPlayer播放音频和视频，首先必须了解MediaPlayer的状态问题。下面是Google提供的MediaPlayer的状态图，基本上只要明白了，在MediaPlayer的状态上。就不会出问题了。



还有什么不明白的，可以详细的看看Google提供的API。

要想用MediaPlayer所写的的音频播放程序健壮的话，不仅需要了解MediaPlayer的各种状态，还必须对MediaPlayer的各个监听事件和回调方法做出必要的设定。



可以根据自己的需要，设置不同的监听方法。

下面是Copy别人的代码，写的不错，搬来壮壮场面。

1、这是布局的文件main.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical" >

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_gravity="top"

android:orientation="horizontal" >

<Button

android:id="@+id/btnPlayUrl"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="播放网络音频" />

<Button

android:id="@+id/btnPause"

android:layout_width="80dip"

android:layout_height="wrap_content"

android:text="暂停" />

<Button

android:id="@+id/btnStop"

android:layout_width="80dip"

android:layout_height="wrap_content"

android:text="停止" />

</LinearLayout>

<LinearLayout

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_gravity="top"

android:orientation="horizontal" >

<SeekBar

android:id="@+id/skbProgress"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_vertical"

android:layout_weight="1.0"

android:max="100"

android:paddingLeft="10dip"

android:paddingRight="10dip" />

</LinearLayout>

</LinearLayout>

2、Player.java 封装了MediaPlayer的播放

package com.tao.test;

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.media.MediaPlayer.OnErrorListener;

import android.os.Handler;

import android.os.Message;

import android.util.Log;

import android.widget.SeekBar;

public class Player implements OnBufferingUpdateListener, OnCompletionListener,

MediaPlayer.OnPreparedListener ,OnErrorListener{

public MediaPlayer mediaPlayer;

private SeekBar skbProgress;

private Timer mTimer = new Timer();

public Player(SeekBar skbProgress) {

this.skbProgress = skbProgress;

try {

mediaPlayer = new MediaPlayer();

mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

mediaPlayer.setOnBufferingUpdateListener(this);

mediaPlayer.setOnPreparedListener(this);

mediaPlayer.setOnCompletionListener(this);

} catch (Exception e) {

Log.e("mediaPlayer", "error", e);

}

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);

}

}

};

//处理消息

Handler handleProgress = new Handler() {

public void handleMessage(Message msg) {

int position = mediaPlayer.getCurrentPosition();

int duration = mediaPlayer.getDuration();

if (duration > 0) {

int pos = skbProgress.getMax() * position / duration;

skbProgress.setProgress(pos);

}

};

};

public void playUrl(String videoUrl) {

try {

mediaPlayer.reset();

mediaPlayer.setDataSource(videoUrl);

mediaPlayer.prepare();// prepare之后自动播放

} catch (IllegalArgumentException e) {

e.printStackTrace();

} catch (IllegalStateException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

public void pause() {

mediaPlayer.pause();

}

public void play() {

mediaPlayer.start();

}

public void stop() {

if (mediaPlayer != null) {

mediaPlayer.stop();

mediaPlayer.release();

mediaPlayer = null;

}

}

/**

* 通过onPrepared播放

*/

public void onPrepared(MediaPlayer arg0) {

arg0.start();

Log.e("mediaPlayer", "onPrepared");

}

public void onCompletion(MediaPlayer arg0) {

Log.e("mediaPlayer", "onCompletion");

}

public void onBufferingUpdate(MediaPlayer arg0, int bufferingProgress) {

skbProgress.setSecondaryProgress(bufferingProgress);

int currentProgress = skbProgress.getMax()

* mediaPlayer.getCurrentPosition() / mediaPlayer.getDuration();

Log.e(currentProgress + "% play", bufferingProgress + "% buffer");

}

public boolean onError(MediaPlayer mp, int what, int extra) {

return false;

}

}

3、TestMedia.java 测试用的Activity

package com.tao.test;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.SeekBar;

public class TestMedia extends Activity {

private Button btnPause, btnPlayUrl, btnStop;

private SeekBar skbProgress;

private Player player;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

this.setTitle("在线音乐播放---hellogv编写");

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(skbProgress);

}

class ClickEvent implements OnClickListener {

public void onClick(View arg0) {

if (arg0 == btnPause) {

player.pause();

} else if (arg0 == btnPlayUrl) {

// 在百度MP3里随便搜索到的,大家可以试试别的链接

String url = "http://219.138.125.22/myweb/mp3/CMP3/JH19.MP3";

player.playUrl(url);

} else if (arg0 == btnStop) {

player.stop();

}

}

}

class SeekBarChangeEvent implements SeekBar.OnSeekBarChangeListener {

int progress;

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();

}

public void onStartTrackingTouch(SeekBar seekBar) {

}

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);

}

}

}

转载/article/2232625.html