顯示所有音樂的SD卡

Question

我使用代碼的形式在本頁面：

http://z4android.blogspot.com/2011/06/displaying-list-of-music-files-stored.html

的代碼工作，但不是洙不錯。 當我試圖向下滾動時，ListView不斷重複列表中的歌曲。

我一直在尋找一些替代的代碼，但我還沒有發現任何。

感謝您的任何幫助。

Answer 1

我不能完全確定到底是什麼原因導致你提到的問題，但試試這個代碼。

private MediaPlayer mMediaPlayer; 
private String[] mMusicList; 

/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 

    mMediaPlayer = new MediaPlayer(); 

    ListView mListView = (ListView) findViewById(R.id.listView1); 

    mMusicList = getMusic(); 

    ArrayAdapter<String> mAdapter = new ArrayAdapter<String>(this, 
    android.R.layout.simple_list_item_1, mMusicList); 
    mListView.setAdapter(mAdapter); 

    mListView.setOnItemClickListener(new OnItemClickListener() { 

    @Override 
    public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, 
    long arg3) { 
     try { 
     playSong(mMusicList[arg2]); 
     } catch (IllegalArgumentException e) { 
     e.printStackTrace(); 
     } catch (IllegalStateException e) { 
     e.printStackTrace(); 
     } catch (IOException e) { 
     e.printStackTrace(); 
     } 
    } 
    }); 
} 

private String[] getMusic() { 
    final Cursor mCursor = managedQuery(
    MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, 
    new String[] { MediaStore.Audio.Media.DISPLAY_NAME }, null, null, 
    "LOWER(" + MediaStore.Audio.Media.TITLE + ") ASC"); 

    int count = mCursor.getCount(); 

    String[] songs = new String[count]; 
    int i = 0; 
    if (mCursor.moveToFirst()) { 
    do { 
     songs[i] = mCursor.getString(0); 
     i++; 
    } while (mCursor.moveToNext()); 
    } 

    mCursor.close(); 

    return songs; 
} 

private void playSong(String path) throws IllegalArgumentException, 
IllegalStateException, IOException { 
    String extStorageDirectory = Environment.getExternalStorageDirectory() 
    .toString(); 

    path = extStorageDirectory + File.separator + path; 

    mMediaPlayer.reset(); 
    mMediaPlayer.setDataSource(path); 
    mMediaPlayer.prepare(); 
    mMediaPlayer.start(); 
} 

Answer 2

這裏的代碼有超級越野車。

的getView沒有任何意義。那個gc（）在那裏做什麼？！什麼是所有moveToPosition（）調用。

這裏的改寫

 public View getView(int position, View convertView, ViewGroup parent) { 
       TextView tv = null; 
       String id = null; 
       if (convertView == null) { 
        tv = new TextView(getApplicationContext()); 
       } else 
        tv = (TextView) convertView; 

       music_column_index = musiccursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME); 
       id = musiccursor.getString(music_column_index); 
       music_column_index = musiccursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE); 
       id += " Size(KB): " + musiccursor.getString(music_column_index); 

       tv.setText(id); 
       return tv; 
     } 

Answer 3

試試這個代碼

public View getView(int position, View convertView, ViewGroup parent) { 
System.gc(); 
String id = null; 
TextView tv; 
if (convertView == null) { 
tv = new TextView(mContext.getApplicationContext()); 
} else{ 
tv = (TextView) convertView; 
} 
musiccursor.moveToPosition(position); 
music_column_index = musiccursor 
.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME); 
id = musiccursor.getString(music_column_index); 
music_column_index = musiccursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE); 
id += " Size(KB):" + musiccursor.getString(music_column_index); 
tv.setText(id); 
return tv; 
} 

Answer 4

安德烈亞斯答案的代碼是這樣做的正確方法，但這些代碼並沒有得到文件的絕對路徑。 這會導致mMediaPlayer.prepare();丟棄IOException: Prepare failed. status=0x1。

下面是代碼來獲取文件的路徑與文件名一起：

private String[] mAudioPath; 
private MediaPlayer mMediaPlayer; 
private String[] mMusicList; 


@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 

    mMediaPlayer = new MediaPlayer(); 

    ListView mListView = (ListView) findViewById(R.id.listView1); 

    mMusicList = getAudioList(); 

    ArrayAdapter<String> mAdapter = new ArrayAdapter<String>(this, 
    android.R.layout.simple_list_item_1, mMusicList); 
    mListView.setAdapter(mAdapter); 

    mListView.setOnItemClickListener(new OnItemClickListener() { 

    @Override 
    public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, 
    long arg3) { 
    try { 
     playSong(mAudioPath[arg2]); 
    } catch (IllegalArgumentException e) { 
     e.printStackTrace(); 
    } catch (IllegalStateException e) { 
     e.printStackTrace(); 
    } catch (IOException e) { 
     e.printStackTrace(); 
    } 
    } 
    }); 
} 

private String[] getAudioList() { 
    final Cursor mCursor = getContentResolver().query(
      MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, 
      new String[] { MediaStore.Audio.Media.DISPLAY_NAME, MediaStore.Audio.Media.DATA }, null, null, 
      "LOWER(" + MediaStore.Audio.Media.TITLE + ") ASC"); 

    int count = mCursor.getCount(); 

    String[] songs = new String[count]; 
    String[] mAudioPath = new String[count]; 
    int i = 0; 
    if (mCursor.moveToFirst()) { 
     do { 
      songs[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME)); 
      mAudioPath[i] = mCursor.getString(mCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA)); 
      i++; 
     } while (mCursor.moveToNext()); 
    } 

    mCursor.close(); 

    return songs; 
} 

現在，我們有絕對的路徑，我們並不需要再次獲取路徑。所以：

private void playSong(String path) throws IllegalArgumentException, 
    IllegalStateException, IOException { 

    Log.d("ringtone", "playSong :: " + path); 

    mMediaPlayer.reset(); 
    mMediaPlayer.setDataSource(path);  
//mMediaPlayer.setLooping(true); 
    mMediaPlayer.prepare(); 
    mMediaPlayer.start(); 
} 

確保使用：

playSong(mAudioPath[arg2]); 

代替：

playSong(mMusicList[arg2]); 

在ListView OnItemClickListener。

要獲得軌道（看起來比帶擴展整個文件名更優雅）的只有標題中使用：代替

`MediaStore.Audio.Media.TITLE` 

：

`MediaStore.Audio.Media.DISPLAY_NAME`