HtmlPlaceholder moves when scrolling

[Nitin Patel]

Hi,

I'm experiencing a problem with the HtmlPlaceholder when used in a scrollviewer.  Here is a snippet of the XAML:

 <ScrollViewer VerticalScrollBarVisibility="Auto" x:Name="m_scrollViewer" Background="Transparent" >
<telerik:RadExpander />
<telerik:RadExpander />
<telerik:RadExpander />
<telerik:RadExpander />

    <telerik:RadExpander ExpandDirection="Down" VerticalAlignment="Top" HorizontalAlignment="Stretch"
                                    animation:AnimationManager.IsAnimationEnabled="False">
            <telerik:RadExpander.Header>
                <TextBlock Text="Text"></TextBlock>
            </telerik:RadExpander.Header>
            <telerik:RadExpander.Content>
                <StackPanel>
  <navigation:RadTabControl x:Name="m_tabHtmlText" Visibility="Visible" Margin="5" Grid.Column="0" Grid.Row="5" Grid.ColumnSpan="5"  >
                <navigation:RadTabItem Header="HTML">
                    <navigation:RadTabItem.Content>
                        <StackPanel x:Name="m_placeholderPanel">
                            <telerikControls:RadHtmlPlaceholder Margin="0 10 0 0" x:Name="m_placeholderHTML" Height="400" RespectSilverlightLayoutMeasure="True"/>
                        </StackPanel>
                    </navigation:RadTabItem.Content>
                </navigation:RadTabItem>
                <navigation:RadTabItem Header="Text">
                    <navigation:RadTabItem.Content>
                        <TextBox x:Name="text" MinHeight="400" MaxHeight="400" VerticalScrollBarVisibility="Auto"></TextBox>
                    </navigation:RadTabItem.Content>
                </navigation:RadTabItem>
            </navigation:RadTabControl>
                </StackPanel>
            </telerik:RadExpander.Content>
        </telerik:RadExpander>

 </Scrollviewer>

There are several expanders on this screen.  The one with the placeholder is about halfway down the screen.  I need the scrollviewer as a container because the page is quite large, especially with all the expanders expanded.

The issue I'm experiencing is that when I scroll, the placeholder eventually starts to move and appear to be not part of its container any longer.  It doesn't matter if I click the scrollviewer or use the mousewheel to scroll.  If I scroll slowly, it seems to re-adjust and display properly for the most part.  The faster I scroll, the more it moves down the page.  Even if it adjusts, eventually it can no longer adjust correctly.  When I scroll far enough down so that the placeholder is at the top of the viewport, it seems to jump a bit down on the page.

Have you seen this behavior?  Is there a workaround or fix to get it to "stick" to its m_tabHtmlText container?

Thanks.

[Petar Mladenov]

Hi Nitin Patel,

We are aware of similar issues in the RadHTMLPlaceHolder. However, I am unable to reproduce your issue. Could you please examine my test project and let me know if I have missed something. You could change it and send it back. This way we could investigate and provide you with an elegant workaround. Thank you in advance.

Greetings,
Petar Mladenov
the Telerik team

[B]

Hi,

I am having the same problem. My issue happens when you put the HtmlPlaceholder inside a childwindow. Can you verify this and suggest a fix/workaround?

Thanks Bruce

[Petar Mladenov]

Hello B,

 We are aware of this issue. The HTMLPlaceHolder does not work / render correctly in ChildWindow. We highly suggest you to use our RadWindow instead. Please let us know if you need further info or assistance.

Best wishes,
Petar Mladenov
the Telerik team