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public class MediaScanner implements MediaScannerConnection.MediaScannerConnectionClient {

    private MediaScannerConnection mMediaScannerConnection;
    private File mFile;

    public MediaScanner(Context context, File file) {
        mFile = file;
        mMediaScannerConnection = new MediaScannerConnection(context, this);
        mMediaScannerConnection.connect();
    }

    @Override
    public void onMediaScannerConnected() {
        mMediaScannerConnection.scanFile(mFile.getAbsolutePath(), null);
    }

    @Override
    public void onScanCompleted(String path, Uri uri) {
        mMediaScannerConnection.disconnect();
    }
}

new MediaScanner(context, file);