Restrictions and Tips for Creating a Silverlight Control

• The control must derive from System.Windows.FrameworkElement.
• The control must have a parameterless constructor.
• Any property that you want to be able to configure through the Designer should be exposed as a standard Silverlight dependency property.
  • The property can be driven by a binding or expression in the Silverlight Designer.
  • For simple data types, the Designer provides a default property editor to all users so that a literal value for the property can be configured.
  • For data types where the default property editor is not sufficient, custom data type editors can be created. For more information, see Create a Custom Data Type Editor for the Silverlight Designer.
  • These properties should be of a data type that can be serialized to XAML.
    Note: There is a known issue with using GUID as a data type.
  • For complex data types, if a property using this type is not being persisted, it may help to initialize the default value of the property using the SetValue method as described below.
• If you want the property to be configurable through the designer, the Editor-Browsable attribute should be set to Always or Advanced.
• The Category attribute can be used to specify the category this property appears in.

    public static readonly DependencyProperty InstructionsProperty 
= 
DependencyProperty.Register("Instructions", typeof(string), 
typeof(MyCustomControl), new 
PropertyMetadata("Please enter in the values below."));
    [EditorBrowsable(EditorBrowsableState.Always), 
Category("Definition")]
    public String Instructions
{
              get { return GetValue(InstructionsProperty) as 
String; }
              set { SetValue(InstructionsProperty, value); }
}    
         

   public HelpfulDataGrid()
              { 
                  SetValue(PopupDataProperty, new CustomList());
                  //Rest of constructor code here
               }