private void ExecuteOpenImageFile()
        {
            System.Windows.Forms.OpenFileDialog openFileDialog = new System.Windows.Forms.OpenFileDialog();
            openFileDialog.Filter = "PNG Files (.png)|*.png|JPG Files (.jpg)|*.jpg|JPEG Files (.jpeg)|*.jpeg|All Files (*.*)|*.*";
            openFileDialog.FilterIndex = 1;

            if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                Model.Image NewImage = new Model.Image(openFileDialog.FileName);
                ImageList.Add(NewImage);
                XMLMedia XMLImage = new XMLMedia();
                XMLImage.LoadXML("Image.xml");
                XMLImage.AddMedia(NewImage);
                XMLImage.WriteXML("Image.xml");
            }
        }
        private void ExecuteOpenVideoFile()
        {
            System.Windows.Forms.OpenFileDialog openFileDialog = new System.Windows.Forms.OpenFileDialog();
            openFileDialog.Filter = "MP4 Files (.mp4)|*.mp4|WMV Files (.wmv)|*.wmv";
            openFileDialog.FilterIndex = 1;

            if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                Model.Video NewVideo = new Model.Video(openFileDialog.FileName);
                VideoList.Add(NewVideo);
                XMLMedia XMLVideo = new XMLMedia();
                XMLVideo.LoadXML("Video.xml");
                XMLVideo.AddMedia(NewVideo);
                XMLVideo.WriteXML("Video.xml");
            }
        }
        private void ExecuteOpenMusicFile()
        {
            System.Windows.Forms.OpenFileDialog openFileDialog = new System.Windows.Forms.OpenFileDialog();
            openFileDialog.Filter = "MP3 Files (.mp3)|*.mp3|All Files (*.*)|*.*";
            openFileDialog.FilterIndex = 1;

            if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                Model.Music NewMusic = new Model.Music(openFileDialog.FileName);
                MusicList.Add(NewMusic);
                XMLMedia XMLMusic = new XMLMedia();
                XMLMusic.LoadXML("Music.xml");
                XMLMusic.AddMedia(NewMusic);
                XMLMusic.WriteXML("Music.xml");
            }
        }