Question

我试图制作一个MP3播放器应用程序，当我从手机上运行它时，它只能读取SD卡上的MP3。它不会从卡中存在的子文件夹中读取任何MP3。我想让它显示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

Android SDK中有MusicRetriever示例。它使用ContentResolver。

Answer 2

File home = new File(MEDIA_PATH);

然后

walkdir(home);

WalkDir方法

public void walkdir(File dir) {
String Pattern = ".mp3";
File listFile[] = dir.listFiles();
if (listFile != null) {
for (int i = 0; i < listFile.length; i++) {
if (listFile[i].isDirectory()) {
walkdir(listFile[i]);
} else {
if (listFile[i].getName().endsWith(Pattern)){
  //Do what ever u want
  // add the path to hash map    
}
}
}  
}  
}

更好地使用增强的for循环，如blackbelt @

所示

Delete only .jpg files from folder in android

而不是删除添加hahsmap的路径

如何访问SD卡中所有子文件夹中的所有mp3文件？

2 个答案: