本文介绍Android MediaPlayer的 使用,MediaPlayer可以播放音频和视频,另外也可以通过VideoView来播放视频,虽然VideoView比MediaPlayer简单易 用,但定制性不如用MediaPlayer,要视情况选择了。MediaPlayer播放音频比较简单,但是要播放视频就需要SurfaceView。 SurfaceView比普通的自定义View更有绘图上的优势,它支持完全的OpenGL ES库。
先贴出本文程序运行结果的截图,上面是播放/停止音频,可用SeekBar来调进度,下面是播放/停止视频,也是用SeekBar来调进度:
main.xml的源码:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/LinearLayout01"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<SeekBar
android:id="@+id/SeekBar01"
android:layout_height="wrap_content"
android:layout_width="fill_parent"></SeekBar>
<LinearLayout
android:id="@+id/LinearLayout02"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<Button
android:id="@+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="播放音频"></Button>
<Button
android:id="@+id/Button02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="停止播放"></Button>
</LinearLayout>
<SeekBar
android:id="@+id/SeekBar02"
android:layout_height="wrap_content"
android:layout_width="fill_parent"></SeekBar>
<SurfaceView
android:id="@+id/SurfaceView01"
android:layout_width="fill_parent"
android:layout_height="250px"></SurfaceView>
<LinearLayout
android:id="@+id/LinearLayout02"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/Button03"
android:text="播放视频"></Button>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="停止播放"
android:id="@+id/Button04"></Button>
</LinearLayout>
</LinearLayout>
本文程序的源码,有点长:
package com.testMedia;
import java.io.IOException;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Activity;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.SeekBar;
import android.widget.Toast;
public class testMedia extends Activity {
/** Called when the activity is first created. */
private SeekBar skb_audio = null;
private Button btn_start_audio = null;
private Button btn_stop_audio = null;
private SeekBar skb_video = null;
private Button btn_start_video = null;
private Button btn_stop_video = null;
private SurfaceView surfaceView;
private SurfaceHolder surfaceHolder;
private MediaPlayer m = null;
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
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// ----------Media控件设置---------//
m = new MediaPlayer();
// 播放结束之后弹出提示
m.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer arg0) {
Toast.makeText(testMedia.this, "结束", 1000).show();
m.release();
}
});
// ----------定时器记录播放进度---------//
mTimer = new Timer();
mTimerTask = new TimerTask() {
@Override
public void run() {
if (isChanging == true)
return;
if (m.getVideoHeight() == 0)
skb_audio.setProgress(m.getCurrentPosition());
else
skb_video.setProgress(m.getCurrentPosition());
}
};
mTimer.schedule(mTimerTask, 0, 10);
btn_start_audio = (Button) this.findViewById(R.id.Button01);
btn_stop_audio = (Button) this.findViewById(R.id.Button02);
btn_start_audio.setOnClickListener(new ClickEvent());
btn_stop_audio.setOnClickListener(new ClickEvent());
skb_audio = (SeekBar) this.findViewById(R.id.SeekBar01);
skb_audio.setOnSeekBarChangeListener(new SeekBarChangeEvent());
btn_start_video = (Button) this.findViewById(R.id.Button03);
btn_stop_video = (Button) this.findViewById(R.id.Button04);
btn_start_video.setOnClickListener(new ClickEvent());
btn_stop_video.setOnClickListener(new ClickEvent());
skb_video = (SeekBar) this.findViewById(R.id.SeekBar02);
skb_video.setOnSeekBarChangeListener(new SeekBarChangeEvent());
surfaceView = (SurfaceView) findViewById(R.id.SurfaceView01);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.setFixedSize(100, 100);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
// ----------按键事件处理---------//
class ClickEvent implements View.OnClickListener {
@Override
public void onClick(View v) {
if (v == btn_start_audio) {
m.reset();// 恢复到未初始化的状态
m = MediaPlayer.create(testMedia.this, R.raw.big);// 读取音频
skb_audio.setMax(m.getDuration());// 设置SeekBar的长度
try {
m.prepare(); // 准备
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
m.start(); // 播放
} else if (v == btn_stop_audio || v == btn_stop_video) {
m.stop();
} else if (v == btn_start_video) {
m.reset();// 恢复到未初始化的状态
m = MediaPlayer.create(testMedia.this, R.raw.test);// 读取视频
skb_video.setMax(m.getDuration());// 设置SeekBar的长度
m.setAudioStreamType(AudioManager.STREAM_MUSIC);
m.setDisplay(surfaceHolder);// 设置屏幕
try {
m.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();
}
m.start();
}
}
}
// ----------SeekBar进度改变事件---------//
class SeekBarChangeEvent implements SeekBar.OnSeekBarChangeListener {
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
isChanging = true;
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
m.seekTo(seekBar.getProgress());
isChanging = false;
}
}
}