Windows Forms: resources, custom controls

Custom control

• Custom controls displaying a bitmap clipped by curves or a polygon:
  • the clipping is always set using 4 points
  • points define a polygon or curves (Splines)
  • all points are situated inside the control
• Implementation details:
  • Custom Control (inherited from System.Windows.Forms.Control)
  • the control has an icon visible on the toolbox (pic.1)
  • the control has 3 properties: ClipRegionType, Points, SourceImage (pic. 2 and 3)
    • ClipRegionType - the way of joining points: Spline (default), Polygon
    • Points - Point[4] type (see below)
    • SourceImage - Image type, the image to draw
  • all properties must be placed in Image section, description must be provided (see pic. 3)
  • change of any property should refresh the control (during editing in Visual Studio)
  • use Color.Pink color as a background in edit mode
  • use AntiAlias and double buffering
• Points property editor:
• use Editor attribute
• the class of the editor must be inherited from UITypeEditor
• override the following methods:
  • EditValue
  • GetEditStyle (use UITypeEditorEditStyle.DropDown style)
• control used for edition of this property is of the same type as the control being edited
• user's actions (pic. 4) :
  • moving of points
  • double click - toogle Spline/Polygon mode
• the content of the control need not to be refreshed after changing any point's coordinations in property grid
• Hints:
  • classes, methods, properties:
    • ToolboxBitmapAttribute
    • BrowsableAttribute
    • CategoryAttribute
    • DefaultValueAttribute
    • DescriptionAttribute
    • EditorAttribute
    • Component.DesignMode
    • UITypeEditor class