How to scan all mp3 files and not only from specific path for an android media player I make

Question

So i found this tutorial http://www.androidhive.info/2012/03/android-building-audio-player-tutorial/ on how to make a music player.

The thing is that it only gets mp3 files inside /sdcard/Music/ and I also want to get mp3 files that are inside folders inside Music folder.

So i've changed the function that returns the songs list to a recursive function but it doesn't work. could you spot my mistake in the code?

filesList is from type File[] and songList is ArrayList>. when this function is first called it gets path= "/sdcards/Music/"

    public ArrayList<HashMap<String, String>> getPlayList(String path)
{

    File home = new File(path);
    filesList=home.listFiles();

    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);
        }


    }




        for(int i=0;i<filesList.length;i++)
    {
        if((filesList[i].isDirectory()))
        getPlayList(filesList[i].getAbsolutePath());
    }




    return songsList;
}

Answer 1

this code work for me, try to add

String media_path = Environment.getExternalStorageDirectory().getPath();
    String[] splitPath= media_path .split("/");
    final String MEDIA_PATH = "/" + splitPath[1] + "/";
    private ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();
    private String mp3Pattern = ".mp3";

and replace your java code to this

// Constructor
    public SongsManager() {

    }

    /**
     * Function to read all mp3 files and store the details in
     * ArrayList
     * */
    public ArrayList<HashMap<String, String>> getPlayList() {
        System.out.println(MEDIA_PATH);
        if (MEDIA_PATH != null) {
            File home = new File(MEDIA_PATH);
            File[] listFiles = home.listFiles();
            if (listFiles != null && listFiles.length > 0) {
                for (File file : listFiles) {
                    System.out.println(file.getAbsolutePath());
                    if (file.isDirectory()) {
                        scanDirectory(file);
                    } else {
                        addSongToList(file);
                    }
                }
            }
        }
        // return songs list array
        return songsList;
    }

    private void scanDirectory(File directory) {
        if (directory != null) {
            File[] listFiles = directory.listFiles();
            if (listFiles != null && listFiles.length > 0) {
                for (File file : listFiles) {
                    if (file.isDirectory()) {
                        scanDirectory(file);
                    } else {
                        addSongToList(file);
                    }

                }
            }
        }
    }

    private void addSongToList(File song) {
        if (song.getName().endsWith(mp3Pattern)) {
            HashMap<String, String> songMap = new HashMap<String, String>();
            songMap.put("songTitle",
                    song.getName().substring(0, (song.getName().length() - 4)));
            songMap.put("songPath", song.getPath());

            // Adding each song to SongList
            songsList.add(songMap);
        }
    }

but this code load slowly :(

Answer 2

I can see a few mistakes, but the biggest one is that when you recurse, you throw away the resulting map.

Other problems:

• You recurse for every file that doesn't have one of the listed suffixes ... but you should really be recursing for directories only.

• Your method calls listFiles(...) up to three times per directory.

• Your method could call listFiles(...) on a File that represents a file rather than a directory. That will return a null and you will get an NPE if you don't test for it. (And since you recurse on files too ...)

• A HashMap is probably a poor choice for representing a "song". Create a custom class.

• Testing for some boolean expression == false is lame. Use the ! operator!