【菜鸟学安卓】- Mp3播放器

做一个简单的Mp3播放器的主要内容包括：

1.获取手机中的mp3文件

在手机中有一个内容提供者供我们使用

主要就是下面的语句来获取

<pre name="code" class="java">Cursor cursor = getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null, MediaStore.Audio.Media.DEFAULT_SORT_ORDER); 

////歌曲ID：MediaStore.Audio.Media._ID//int id = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media._ID));  ////歌曲的名称 ：MediaStore.Audio.Media.TITLE//String tilte = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));  ////歌曲的专辑名：MediaStore.Audio.Media.ALBUM//String album = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM));  ////歌曲的歌手名： MediaStore.Audio.Media.ARTIST //String artist = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));  ////歌曲文件的路径 ：MediaStore.Audio.Media.DATA//String url = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));    ////歌曲的总播放时长 ：MediaStore.Audio.Media.DURATION//int duration = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));    ////歌曲文件的大小 ：MediaStore.Audio.Media.SIZE//int size =(int)cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));

2.播放获取出来的mp3文件

MediaPlayer mediaPlayer = new MediaPlayer();//实例化一个媒体播放器

mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);//设置媒体播放器的音乐类型

mediaPlayer.setDataSource(path);//设置播放文件的路径

mediaPlayer.setLooping(true);

mediaPlayer.prepareAsync();//播放准备

mediaPlayer.start();//开始播放

主文件代码如下：

由于博主只是学习下这两部分的内容，所以其中有些地方是有问题的，看主要内容就好。

package com.mp3palyer;import java.io.File;import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.content.Intent;import android.database.Cursor;import android.media.AudioManager;import android.media.MediaPlayer;import android.media.MediaPlayer.OnCompletionListener;import android.media.MediaPlayer.OnErrorListener;import android.media.MediaPlayer.OnPreparedListener;import android.os.Bundle;import android.provider.MediaStore;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.ListView;import android.widget.TextView;import android.widget.Toast;public class MainActivity extends Activity implements OnClickListener {private MediaPlayer mediaPlayer;private LinearLayout toControlView;private LinearLayout playBtn;private LinearLayout favoriteBtn;private LinearLayout nextBtn;private ImageView playBtnImage;private String currentPath;private ListView mp3ListView;private List<Mp3Info> mp3InfoList = new ArrayList<Mp3Info>();private int currentPosition = 0;private int playMode = 0;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);findMp3();if(mp3InfoList != null)currentPath = mp3InfoList.get(0).getUrl();findViewId();}private void findMp3() {Cursor cursor = getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null, MediaStore.Audio.Media.DEFAULT_SORT_ORDER); System.out.println("一共有  "+cursor.getCount());while(cursor.moveToNext()){String url = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));if(url.endsWith(".mp3")){Mp3Info mp3Info = new Mp3Info();int id = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media._ID));  int duration = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));    int size =(int)cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));String tilte = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE));  String album = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ALBUM));  String artist = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));  mp3Info.setId(id);mp3Info.setDuration(duration);mp3Info.setSize(size);mp3Info.setTilte(tilte);mp3Info.setArtist(artist);mp3Info.setAlbum(album);mp3Info.setUrl(url);mp3InfoList.add(mp3Info);}}cursor.close();}private void findViewId(){toControlView = (LinearLayout)findViewById(R.id.toControlView);playBtn = (LinearLayout)findViewById(R.id.playBtn);favoriteBtn = (LinearLayout)findViewById(R.id.favoriteBtn);nextBtn = (LinearLayout)findViewById(R.id.nextBtn);playBtnImage = (ImageView)findViewById(R.id.playBtnImage);mp3ListView = (ListView)findViewById(R.id.myListView);Mp3Adapter mp3ListAdapter = new Mp3Adapter(mp3InfoList);mp3ListView.setAdapter(mp3ListAdapter);toControlView.setOnClickListener(this);playBtn.setOnClickListener(this);favoriteBtn.setOnClickListener(this);nextBtn.setOnClickListener(this);mp3ListView.setOnItemClickListener(new ListView.OnItemClickListener(){@Overridepublic void onItemClick(AdapterView<?> parent, View view, int position, long id) {String path = mp3InfoList.get(position).getUrl();//获取路径play(path);//播放音乐}});}@Overridepublic void onClick(View v) {switch(v.getId()){case R.id.toControlView:startActivity(new Intent(this,PlayActivity.class));break;case R.id.favoriteBtn:break;case R.id.playBtn:if(playMode == 0){playMode = 1;playBtnImage.setImageResource(R.drawable.ao9);continuePlay(currentPath);}else{playMode = 0;playBtnImage.setImageResource(R.drawable.aoa);pause();}break;case R.id.nextBtn:playNext(mp3InfoList.get(currentPosition+1).getUrl());break;default:}}//播放一个新的private void playNew(String path){try {File file = new File(path);if(file.exists()&&file.length()>0){mediaPlayer = new MediaPlayer();mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);mediaPlayer.setDataSource(path);mediaPlayer.setLooping(true);mediaPlayer.prepareAsync();mediaPlayer.setOnPreparedListener(new OnPreparedListener(){@Overridepublic void onPrepared(MediaPlayer mp) {mediaPlayer.start();}});mediaPlayer.setOnCompletionListener(new OnCompletionListener(){@Overridepublic void onCompletion(MediaPlayer mp) {//mediaPlayer.}});mediaPlayer.setOnErrorListener(new OnErrorListener(){@Overridepublic boolean onError(MediaPlayer mp, int what, int extra) {return false;}});}else{Toast.makeText(this, "文件不存在！", 0).show();}} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}//播放默认的private void play(String path){//先停止当前的播放if(mediaPlayer != null){stop();}//播放新的playNew(path);}//播放下一首private void playNext(String path){play(path);}//暂停private void pause(){if(mediaPlayer != null && mediaPlayer.isPlaying()){mediaPlayer.pause();}}//停止private void stop(){if(mediaPlayer != null&& mediaPlayer.isPlaying()){mediaPlayer.stop();mediaPlayer.release();mediaPlayer = null;}}//继续播放private void continuePlay(String path){if(mediaPlayer != null){mediaPlayer.start();}else{playNew(path);}}public class Mp3Adapter extends BaseAdapter{private List<Mp3Info> mp3List;public Mp3Adapter(List<Mp3Info> mp3List){this.mp3List = mp3List;}@Overridepublic int getCount() {if(mp3List != null)return mp3List.size();return 0;}@Overridepublic Object getItem(int position) {// TODO Auto-generated method stubreturn null;}@Overridepublic long getItemId(int position) {// TODO Auto-generated method stubreturn 0;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {View view = null;if(convertView != null){view = convertView;}else{view = View.inflate(MainActivity.this, R.layout.item_list, null);}ImageView musicImage = (ImageView)view.findViewById(R.id.musicImage);TextView musicName= (TextView)view.findViewById(R.id.musicName);TextView musicSinger= (TextView)view.findViewById(R.id.musicSinger);musicName.setText(mp3List.get(position).getTilte());musicSinger.setText(mp3List.get(position).getArtist());return view;}}}