Validation errors of controls inside RadExpander Control

[Prasad]

Hi ,

 

I have enclosed multiple textboxes and drop down controls inside RadExpander control. Some of the controls have Required filed attached.

I have RadExpander collapsed by default. When i expand RadExpander ,Validation errors for these controls are not getting displayed.

But once i expand the RadExpander control and go to a different tab and come back i see the validation errors. I tried to call a command explicitly on expanding the RadExpander control , validations are firing but messages are displayed against the controls. 

 

Let me know if any faced this kind of issue and solution for this.

 

Regards,

Prasad.

[Dinko | Tech Support Engineer]

Hello ,

Thank you for your interest in RadExpander control.

This is because when the expander is collapsed initially its Content (the TextBox in your case) is not added in the application's visual tree until it expands for the first time. This behavior is similar to the one described in the following StackOverflow question. 

What I can suggest you is to wrap the text boxes into an AdornerDecorator. For example:

<telerik:RadExpander Header="Demo" IsExpanded="False" VerticalContentAlignment="Top">
    <AdornerDecorator>
        <TextBox Text="{Binding Text, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True}"  />
        </AdornerDecorator>
</telerik:RadExpander>

Give this approach a try and let me know if it works for you. 

Regards,
Dinko
Progress Telerik

[Prasad]

Hi Dinko,

 

Thanks for response. My issue has been resolved for now. Will get back if i face any further issues.

 

Regards,

Prasad.