android - 如何访问 sdcard 中所有子文件夹中的所有 mp3 文件？

Question

我正在尝试制作一个 mp3 播放器应用程序，当我从我的手机运行它时，它只会读取 SD 卡本身上存在的 MP3。它不会从卡中存在的子文件夹中读取任何 MP3。我希望它显示 SD 卡中的所有 MP3(包括子文件夹)。

public class SongsManager {
// SDCard Path
final String MEDIA_PATH = new String(Environment.getExternalStorageDirectory().getPath());
private ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();

// Constructor
public SongsManager(){

}

/**
 * Function to read all mp3 files from sdcard
 * and store the details in ArrayList
 * */
public ArrayList<HashMap<String, String>> getPlayList(){
    File home = new File(MEDIA_PATH);

    if (home.listFiles(new FileExtensionFilter()).length > 0) {
        for (File file : home.listFiles(new FileExtensionFilter())) {
            HashMap<String, String> song = new HashMap<String, String>();
            song.put("songTitle", file.getName().substring(0, (file.getName().length() - 4)));
            song.put("songPath", file.getPath());

            // Adding each song to SongList
            songsList.add(song);
        }
    }
    // return songs list array
    return songsList;
}


/**
 * Class to filter files which are having .mp3 extension
 * */
class FileExtensionFilter implements FilenameFilter {
    public boolean accept(File dir, String name) {
        return (name.endsWith(".mp3") || name.endsWith(".MP3"));
    }
}  }

Answer 1

有 MusicRetriever Android SDK 中的示例。它使用 ContentResolver .