Using RadControls for WinForms with inherited forms

How To

Use RadControls for WinForms with inherited forms

Problem

When the Modifiers property of a RadControl is set to "protected" or "public" in a base form, the code DOM serialization and the overall design-time behavior of the control is incorrect in the child form.

Considerations

In general, we advise against visual inheritance (inheriting a form that has serialized code from design-time). There are many problems with the code DOM serialization that should be considered. However, in some simple cases it is possible to use visual inheritance.

Solution

To start off, we recommend leaving the Modifiers property of the generated fields in the base form unchanged (for VB developers: it may be better to set Modifiers to Private, but do not set it to Protected or Public). Instead, create a public property that returns the private field and inform the Visual Studio to use that property for serialization. You will have to use the AccessedThroughProperty attribute.

Example

Let's have a form BaseForm with RadRibbonBar in it and a child form DerivedForm that inherits BaseForm. In order to have working design-time for the ribbon in DerivedForm you have to modify the designer file of BaseForm:

partial class BaseForm  
{  
    //......  

    [System.Runtime.CompilerServices.AccessedThroughProperty("MainRibbon")]  
    private Telerik.WinControls.UI.RadRibbonBar radRibbonBar1;  


    public Telerik.WinControls.UI.RadRibbonBar MainRibbon  
    {  
        get { return this.radRibbonBar1; }  
    }  
}

Partial Class BaseForm  
    Inherits System.Windows.Forms.Form  

    '......  

    <System.Runtime.CompilerServices.AccessedThroughProperty("MainRibbon")> _  
    Private RadRibbonBar1 As Telerik.WinControls.UI.RadRibbonBar  


    Public ReadOnly Property MainRibbon() As Telerik.WinControls.UI.RadRibbonBar  
        Get 
            Return Me.RadRibbonBar1  
        End Get 
    End Property 

End Class 

Do not forget to build the project that contains BaseForm before opening DerivedForm in design-time.

Notes

Even though all serialization in the DerivedForm is done through the public property there are some limitations that should be considered:

• Do not modify the control's properties that are serialized via DesignerSerializationVisibility.Content in the BaseForm. If these properties are modified in the BaseForm, their subsequent modifications in DerivedForm will not be serialized;
• Be careful when using UserControls or Panels with child controls in the BaseForm - it is highly possible that subsequent modifications for the child controls in DerivedForm will not work;
• The Visual Studio design-time should not delete the manually written property, but sometimes the attribute of the field is removed. Keep an eye on that code when modifying the base form in design-time.

For more information on how to control the Visual Studio's code DOM serialization see:
http://msdn.microsoft.com/en-us/library/ms973818.aspx