Android : Android Thumbnails inside MediaStore isn't getting refreshed after calling MediaScannerConnection.scanFile

I'm trying to build a Gallery-like app which will perform the following functions on External storage:

• List all the folder that has images inside it


• List all the images that available to the public (will not probe the files inside Android/data)

So far I can list all the images, and folders that have images. However, I later find that these images and folders are not the newest ones: they are not getting refreshed after I put some pictures (say I simply do some screenshots or download some pictures).

And new pictures are not appear even after I call MediaScannerConnection.scanFile.

Except the MediaScannerConnection, I've also tried the expensive Intent.ACTION_MEDIA_SCANNER_SCAN_FILE method with the specified folders, and no luck.

I've browsing on StackOverflow as well as various of sources with people discussing this issue, but none of them can offer a working method.

Sources I've checked/tried:

• http://droidyue.com/blog/2014/01/19/scan-media-files-in-android/


• Trigger mediascanner on specific path (folder), how to?

Code:

How I list all the images:

    private String[] projectionThumbnail = new String[]{MediaStore.Images.Thumbnails._ID, MediaStore.Images.Thumbnails.IMAGE_ID, MediaStore.Images.Thumbnails.DATA};
    private Uri uriThumbnail = MediaStore.Images.Thumbnails.EXTERNAL_CONTENT_URI;

    private String[] projectionFull = new String[]{MediaStore.Images.Media._ID, MediaStore.Images.Media.BUCKET_DISPLAY_NAME, MediaStore.Images.Media.DATA};
    private Uri uriFull = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;


@Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        switch (id) {
            case LOADER_ALL_IMAGES:
                return new CursorLoader(getActivity(), uriThumbnail, projectionThumbnail, null, null, MediaStore.Images.Thumbnails._ID + " DESC");
            default:
                return null;
        }
    }

    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
        switch (loader.getId()) {
            case LOADER_ALL_IMAGES:
                adapter.changeCursor(cursor);
                break;
}
    }
    @Override
    public void onLoaderReset(Loader<Cursor> loader) {
        adapter.changeCursor(null);
    }

// And here's how I init the CursorLoader
LoaderManager lm = getActivity().getLoaderManager();
lm.initLoader(LOADER_ALL_IMAGES, null, this);

Here's how I start scanning the images, I intend to scan the whole External storage, but for now, I'll just scan DCIM, PICTURES and DOWNLOADS just for experiment

    File dcim = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
    File pictures = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
    File downloads = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);

    MediaScannerConnection.scanFile(this,
            new String[]{dcim.getAbsolutePath(), pictures.getAbsolutePath(), downloads.getAbsolutePath()}, new String[]{"image/*", "image/*", "image/*"},
            new MediaScannerConnection.OnScanCompletedListener() {
                public void onScanCompleted(String path, Uri uri) {
                    Log.i("ExternalStorage", "Scanned " + path + ":");
                    Log.i("ExternalStorage", "-> uri=" + uri);
                }
            });

Question:

I did my test on Stock 5.0.2 and 4.4, same result on both of them.

1. Am I doing anything wrong?


2. Why does the MediaScanner not working?