使用FileFilter的ListActivity

Question

我试图扩展一个教程，我发现here关于创建一个简单的文件浏览器。我想添加一个FileFilter只看音频文件。不过，我仍然看到除了在我的字符串数组中定义的文件类型以外的其他文件类型。感谢任何帮助，我可以得到。

public class SDCardExplorer extends ListActivity { 

private String mediapath = new String(Environment.getExternalStorageDirectory().getAbsolutePath()); 

private List<String> item = null; 
private List<String> path = null; 

private TextView mypath; 

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

    mypath = (TextView) findViewById(R.id.mypath); 

    LoadDirectory(mediapath); 
} 

// class to limit the choices shown when browsing to SD card to media files 
public class AudioFilter implements FileFilter { 

    // only want to see the following audio file types 
    private String[] extension = {".aac", ".mp3", ".wav", ".ogg", ".midi", ".3gp", ".mp4", ".m4a", ".amr", ".flac"}; 

    @Override 
    public boolean accept(File pathname) { 

     // if we are looking at a directory/file that's not hidden we want to see it so return TRUE 
     if ((pathname.isDirectory() || pathname.isFile()) && !pathname.isHidden()){ 
      return true; 
     } 

     // loops through and determines the extension of all files in the directory 
     // returns TRUE to only show the audio files defined in the String[] extension array 
     for (String ext : extension) { 
      if (pathname.getName().toLowerCase().endsWith(ext)) { 
       return true; 
      } 
     } 

     return false; 
    }  
} 

private void LoadDirectory(String dirPath) {  

    mypath.setText("Location: " + dirPath); 

    item = new ArrayList<String>(); 
    path = new ArrayList<String>(); 

    File f = new File(dirPath); 
    File[] files = f.listFiles(new AudioFilter()); 

    // If we aren't in the SD card root directory, add "Up" to go back to previous folder 
    if(!dirPath.equals(mediapath)) { 

     item.add("Up"); 
     path.add(f.getParent()); 
    } 

    // Loops through the files and lists them 
    for (int i = 0; i < files.length; i++) { 
     File file = files[i]; 
     path.add(file.getPath()); 

     // Add "/" to indicate you are looking at a folder 
     if(file.isDirectory()) { 
      item.add(file.getName() + "/"); 
     } 
     else { 
      item.add(file.getName()); 
     } 
    } 

    // Displays the directory list on the screen 
    setListAdapter(new ArrayAdapter<String>(this, R.layout.mediaitems, item)); 
} 

}

Answer 1

我认为这个问题是在下面的行：

if ((pathname.isDirectory() || pathname.isFile()) && !pathname.isHidden()){ 
     return true; 
    } 

问题是逻辑说是路径的目录或文件，然后在路径不隐藏。您可能只想查找路径是否为目录。

尝试将其更改为以下：

if (pathname.isDirectory() && !pathname.isHidden()) { 
     return true; 
    }