Android之MediaPlayer播放音乐并实现进度条实例

首先，说明我们是从sd卡里读文件，来播放文件！！

1、效果图：



提前工作，往sd卡里放音乐文件，如图：



2、布局文件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" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="歌曲名："/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="blueflawer.mp3"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="播放"
android:id="@+id/play_pause"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="重置"
android:id="@+id/reset"/>
<SeekBar
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/seekbar"/>
</LinearLayout>3、activity类
package cn.csdn.activity;

import java.io.File;
import java.io.IOException;
import java.util.Timer;
import java.util.TimerTask;

import android.app.Activity;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;

public class MyPlayerActivity extends Activity {
private Button play_pause, reset;
private SeekBar seekbar;
private boolean ifplay = false;
private MediaPlayer player = null;
private String musicName = "blueflawer.mp3";
private boolean iffirst = false;
private Timer mTimer;
private TimerTask mTimerTask;
private boolean isChanging=false;//互斥变量，防止定时器与SeekBar拖动时进度冲突
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
player = new MediaPlayer();
findViews();// 各组件
}

private void findViews() {
play_pause = (Button) findViewById(R.id.play_pause);
reset = (Button) findViewById(R.id.reset);
play_pause.setOnClickListener(new MyClick());
reset.setOnClickListener(new MyClick());

seekbar = (SeekBar) findViewById(R.id.seekbar);
seekbar.setOnSeekBarChangeListener(new MySeekbar());
}

class MyClick implements OnClickListener {
public void onClick(View v) {
File file = new File(Environment.getExternalStorageDirectory(),
musicName);
// 判断有没有要播放的文件
if (file.exists()) {
switch (v.getId()) {
case R.id.play_pause:
if (player != null && !ifplay) {
play_pause.setText("暂停");
if (!iffirst) {
player.reset();
try {
player.setDataSource(file.getAbsolutePath());
player.prepare();// 准备

} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
seekbar.setMax(player.getDuration());//设置进度条
//----------定时器记录播放进度---------//
mTimer = new Timer();
mTimerTask = new TimerTask() {
@Override
public void run() {
if(isChanging==true) {
return;
}
seekbar.setProgress(player.getCurrentPosition());
}
};
mTimer.schedule(mTimerTask, 0, 10);
iffirst=true;
}
player.start();// 开始
ifplay = true;
} else if (ifplay) {
play_pause.setText("继续");
player.pause();
ifplay = false;
}
break;
case R.id.reset:
if (ifplay) {
player.seekTo(0);
} else {
player.reset();
try {
player.setDataSource(file.getAbsolutePath());
player.prepare();// 准备
player.start();// 开始
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
break;
}
}
}
}
//进度条处理
class MySeekbar implements OnSeekBarChangeListener {
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
}

public void onStartTrackingTouch(SeekBar seekBar) {
isChanging=true;
}

public void onStopTrackingTouch(SeekBar seekBar) {
player.seekTo(seekbar.getProgress());
isChanging=false;
}

}
//来电处理
protected void onDestroy() {
if(player != null){
if(player.isPlaying()){
player.stop();
}
player.release();
}
super.onDestroy();
}

protected void onPause() {
if(player != null){
if(player.isPlaying()){
player.pause();
}
}
super.onPause();
}

protected void onResume() {
if(player != null){
if(!player.isPlaying()){
player.start();
}
}
super.onResume();
}

}