I created a folder that's Cuzler in mnt/sdcard and put some mp3 files.. and here codes what I am using..
File cuzFolder = new File(Environment.getExternalStorageDirectory() + "/Cuzler/");
String storageFolder = cuzFolder.getPath();
Uri urlCuz = Uri.parse(storageFolder);
Log.i(TAG, "CUZ: " + urlCuz.toString());
Cursor cur = mContentResolver.query(urlCuz, null,
MediaStore.Audio.Media.IS_MUSIC + " = 1", null, null);
Log.i(TAG, "Query finished. " + (cur == null ? "Returned NULL." : "Returned a cursor."));
cur returns null.. I've given the write/read permissions. I am making a mp3 player that will play some mp3s in a folder in sdcard, the path is true because I am downloading mp3s to this folder and no problem. But I do not understand why query returns null ?
I also tried something like
Uri urlCuz = Uri.parse("content://" + storageFolder);
and gave direct link like mnt/sdcard/Cuzler or /mnt/scard/Cuzler
How can I solve this problem?
public class MainActivity extends AppCompatActivity {
ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.list_view);
ContentResolver resolver = MainActivity.this.getContentResolver();
ArrayList<String> stringArrayList = new ArrayList<String>();
String GENRE_ID = MediaStore.Audio.Genres._ID;
String GENRE_NAME = MediaStore.Audio.Genres.NAME;
String SONG_ID = android.provider.MediaStore.Audio.Media._ID;
String SONG_TITLE = android.provider.MediaStore.Audio.Media.TITLE;
String SONG_ARTIST = android.provider.MediaStore.Audio.Media.ARTIST;
String SONG_ALBUM = android.provider.MediaStore.Audio.Media.ALBUM;
String SONG_YEAR = android.provider.MediaStore.Audio.Media.YEAR;
String SONG_TRACK_NO = android.provider.MediaStore.Audio.Media.TRACK;
String SONG_FILEPATH = android.provider.MediaStore.Audio.Media.DATA;
String SONG_DURATION = android.provider.MediaStore.Audio.Media.DURATION;
String[] genreColumns = {
SONG_ID,
SONG_TITLE
};
if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (shouldShowRequestPermissionRationale(
Manifest.permission.READ_EXTERNAL_STORAGE)) {
// Explain to the user why we need to read the contacts
}
requestPermissions(new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
1);
// MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE is an
// app-defined int constant that should be quite unique
return;
}
Cursor cursor = resolver.query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,genreColumns,null,null,null);
for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext())
// genreIdToGenreNameMap.put(cursor.getString(0), cursor.getString(1));
stringArrayList.add(cursor.getString(1));
cursor.close();
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,stringArrayList);
listView.setAdapter(adapter);
}
}
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