HtmlDataProvider + RadRTB, Html binding set called on init

[Claudio]

Hi everybody,
I have a problem with the Rich Text Box + HtmlDataProvider.
I make a simple an isolated example.

<telerikDocumentsHtml:HtmlDataProvider
            x:Name="provider"
            RichTextBox="{Binding ElementName=rtb}"
            Html="{Binding Text, Mode=TwoWay}" Grid.RowSpan="2" />
<telerik:RadRichTextBox Name="rtb" Margin="20"/>

This is my "main page" and the datacontext is setted to a simple class:

    public class ViewModel
    {
        private string text;
        public string Text
        {
            get { return text; }
            set 
            { 
                text = value; 
            }
        }
    }

the main page ctor works like this:

    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
            var vm = new ViewModel();
            vm.Text = "XXXXXXXXXXX";
            DataContext = vm;
        }
    }


Seems that the SET accessor of the Text property is called TWICE, one during the first set on the ctor of the main page, the second from the binding in the Provider. 
If i use a normal textbox the binding set is not called on the beginning.
How can i avoid this?
Thanks to everybody.
Ray

[Iva Toteva]

Hi Claudio,

This is currently the behavior by design. As the value of the string property you have bound the data provider to may not be valid HTML (which is also the case in your sample), we have decided to update the property with the result of the export the first time the Html property is updated. In this way, the value of the property in the view model will be synchronized with the content of the document at all times.
If you would like to suppress this update, you can download the source code of the controls from your account and implement your own data provider based on ours. Another option would be to implement a custom control containing a RadRichTextBox with a dependency property you can bind to which you can synchronize in an appropriate fashion.

Kind regards,
Iva
the Telerik team

[Claudio]

Thank you for the suggestion, I will adopt a simple workaround to correct unwanted behaviors.
Claudio

[Beaner]

I am having the exact same issue.  I'm tracking dirty screens using the HasChanges() on my domain context and because my string property is always being set twice, my screen is always dirty.  Do you have an example of a solution using a custom control with a dependency property?

[Iva Toteva]

Hello Beaner,

Please find attached a sample application, which includes an implementation of a control encapsulating a RadRichTextBox. The conrol exposes a RichTextProperty which does not update the property it is bound to the first time the control is loaded.

Kind regards,
Iva
the Telerik team

[Beaner]

Thank you!!