What is the String 'volumeName' argument of MediaStore.Audio.Playlists.Members.getContentUri referring to?

Question

I am wanting to query the members of a given playlist. I have the correct playlist id, and want to use a managedQuery() to look at the playlist members in question.

Answer 1

The String "external" works as the volume in MediaStore.Audio.Playlists.Members.getContentUri(volume, playlistId)

This activity prints the songs on an Android, and the playlists, and their contents.

import android.app.Activity;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.util.Log;

public class PlaylistActivity extends Activity {
    private final String [] STAR= {"*"};
    private final String TAG= "list";

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

        Log.i(TAG, "All the titles");
        Uri allaudio_uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
        Cursor ca= managedQuery(allaudio_uri, STAR, null,null,null);
        for(ca.moveToFirst(); !ca.isAfterLast(); ca.moveToNext()){
            if(ca.isFirst()){   // print all the fields of the first song
                for(int k= 0; k