/// <summary>
        ///  play ngẫu nhiên
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void PlayRandomButton_Click(object sender, RoutedEventArgs e)
        {
            var screen = new CountRepeat();

            if (screen.ShowDialog() == true)
            {
                countRepeat = screen.countRepeat;
            }

            Indexes.Clear();
            for (int i = 0; i < operationListBox.Items.Count; i++)
            {
                Indexes.Add(i);
            }

            Random r = new Random();

            _lastIndex = Indexes[r.Next(0, Indexes.Count)];
            Indexes.Remove(_lastIndex);

            if (_isPlaying)
            {
                player.DeletePlayer();
            }

            PlayASong(_lastIndex);
            player.sound.MediaEnded += player_MediaEndedRandom;
        }
        int _isPlayingMiniList = -1;    //đang nghe nhạc ở danh sách tổng
        /// <summary>
        /// Sau khi chọn 1 bài hát trong Bigest list để nghe->nhấn Play button
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void PlayButton_Click(object sender, RoutedEventArgs e)
        {
            int indexSong = operationListBox.SelectedIndex;

            if (indexSong >= 0)
            {
                var screen = new CountRepeat();
                if (screen.ShowDialog() == true)
                {
                    countRepeat = screen.countRepeat;
                }

                if (_isPlaying && indexSong >= 0)
                {
                    player.DeletePlayer();
                    player = null;
                    if (_lastIndex > -1)
                    {
                        Convert[_lastIndex].isPlaying = false;
                    }
                }

                _lastIndex = indexSong;//lưu lại

                PlayButton.Visibility  = Visibility.Collapsed;
                PauseButton.Visibility = Visibility.Visible;
                PlayASong(indexSong);
            }
            else
            {
                System.Windows.MessageBox.Show("No file selected!");
                return;
            }
            player.sound.MediaEnded += player_MediaEnded_PlayOne;
        }
        /// <summary>
        ///
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void PlayAllButton_Click(object sender, RoutedEventArgs e)
        {
            var screen = new CountRepeat();

            if (screen.ShowDialog() == true)
            {
                countRepeat = screen.countRepeat;
            }

            _lastIndex = 0;
            if (_isPlaying)
            {
                player.DeletePlayer();
            }

            PlayASong(_lastIndex);
            player.sound.MediaEnded += player_MediaEnded;
        }