添加项目文件。

Util.DiagramDesigner/ViewModels/SimpleViewModel/VideoItemViewModel.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Text;
+
+namespace Util.DiagramDesigner
+{
+    public class VideoItemViewModel : MediaItemViewModel
+    {
+        protected override string Filter { get; set; } = "视频|*.wmv;*.asf;*.asx;*.rm;*.rmvb;*.mp4;*.3gp;*.mov;*.m4v;*.avi;*.dat;*.mkv;*.flv;*.vob";
+
+        public VideoItemViewModel() : base()
+        {
+        }
+
+        public VideoItemViewModel(IDiagramViewModel parent, MediaDesignerItem designer) : base(parent, designer)
+        {
+
+        }               
+    }
+}