ANDROID_MARS学习笔记_S01原始版_023_MP3PLAYER003_播放mp3

一、简介

1.在onListItemClick中实现点击条目时，跳转到PlayerActivity,mp3info通过Intent传给PlayerActivity

2.PlayerActivity通过android.media.MediaPlayer实现播放，暂停、停止

二、代码
1.xml
(1)player.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="horizontal" android:paddingLeft="10dip"
     android:paddingRight="10dip" android:paddingTop="1dip"
     android:paddingBottom="1dip">
     <ImageButton android:id="@+id/begin" android:layout_width="wrap_content"
         android:layout_height="wrap_content" android:src="@drawable/begin" />
     <ImageButton android:id="@+id/pause" android:layout_width="wrap_content"
         android:layout_height="wrap_content" android:src="@drawable/pause" />
     <ImageButton android:id="@+id/stop" android:layout_width="wrap_content"
         android:layout_height="wrap_content" android:src="@drawable/stop" />
 </LinearLayout>

(2)AndroidManifest.xml注册activity

 <activity android:name=".PlayerActivity" android:label="@string/app_name"/>

2.java
(1)LocalMp3ListActivity.java

点击歌曲时，启动PlayerActivity

     @Override
     protected void onListItemClick(ListView l, View v, int position, long id) {
         Mp3Info info = infos.get(position);
         Intent intent = new Intent();
         intent.putExtra("mp3Info", info);
         intent.setClass(this, PlayerActivity.class);
         startActivity(intent);
     }

(2)PlayerActivity.java

 package tony.mp3player;

 import java.io.File;

 import tony.model.Mp3Info;
 import android.app.Activity;
 import android.content.Intent;
 import android.media.MediaPlayer;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Environment;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.ImageButton;

 public class PlayerActivity extends Activity {

     private ImageButton beginBtn = null;
     private ImageButton pauseBtn = null;
     private ImageButton stopBtn = null;

     private MediaPlayer mediaPlayer = null;
     private Mp3Info info = null;

     private boolean isPlaying = false;
     private boolean isPause = false;
     private boolean isRelease = false;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.player);
         Intent intent = getIntent();
         info = (Mp3Info) intent.getSerializableExtra("mp3Info");
         beginBtn = (ImageButton) findViewById(R.id.begin);
         pauseBtn = (ImageButton) findViewById(R.id.pause);
         stopBtn = (ImageButton) findViewById(R.id.stop);

         beginBtn.setOnClickListener(new BeginListener());
         pauseBtn.setOnClickListener(new PauseListener());
         stopBtn.setOnClickListener(new StopListener());
     }

     class BeginListener implements OnClickListener {
         @Override
         public void onClick(View v) {
             if(!isPlaying) {
                 String path = getMp3Path(info.getMp3Name());
                 mediaPlayer = MediaPlayer.create(PlayerActivity.this, Uri.parse("file://" + path));
                 mediaPlayer.start();
                 isPlaying = true;
                 isRelease = false;
             }
         }
     }

     class PauseListener implements OnClickListener {
         @Override
         public void onClick(View v) {
             if(mediaPlayer != null) {
                 if(!isRelease){
                     if(!isPause) {
                         mediaPlayer.pause();
                         isPause = true;
                     } else {
                         mediaPlayer.start();
                         isPause = false;
                     }
                 }
             }
         }
     }

     class StopListener implements OnClickListener {
         @Override
         public void onClick(View v) {
             if(mediaPlayer != null) {
                 if(isPlaying) {
                     if(!isRelease) {
                         mediaPlayer.stop();
                         mediaPlayer.release();
                         isRelease = true;
                         isPlaying = false;
                     }
                 }
             }
         }
     }

     private String getMp3Path(String mp3Name) {
         String sdCartRoot = Environment.getExternalStorageDirectory().getAbsolutePath();
         String path = sdCartRoot + File.separator + "mp3" + File.separator + mp3Name;
         return path;
     }
 }