/**
  * コンストラクタ
  */
 private WvvFrameSelectorDialog(MediaSource source, WvvFrameSelectedHandler onSelected)
 {
     mOnSelected = onSelected;
     mSource     = source;
     this.InitializeComponent();
     this.DataContext = this;
 }
        /**
         * ダイアログを表示する。
         */
        public static async Task <bool> Show(MediaSource source, FrameworkElement anchor, WvvFrameSelectedHandler onSelected)
        {
            if (null == onSelected)
            {
                return(false);
            }

            var content = new WvvFrameSelectorDialog(source, onSelected);
            await WvvDialog.Show(content, anchor);

            return(true);
        }