Scroll to bottom of HTMLPlaceHolder

[Ólafur Gíslason]

Hi, is it possible to scroll to the bottom of a HTMLPlaceHolder in code?

I am adding to the HTMLSource and the HTMLPlaceHolder  always scrolls to the top?

Before I tried to place the HTMLPlaceHolder   within a ScrollViewer but then it is impossible to get rid of the HTMLPlaceHolder Scrollbars.  I will get a double set of scrollbars.  It is no problem to scroll to the bottom of the ScrollViewer.

I tried unsuccessfully to wire this up in the Page_Load event to get rid of the HTMLPlaceHolder scrollbar 

 (radHtmlPlaceholder1.HtmlPresenter.Children[0] as HtmlElement).SetAttribute("scrolling", "no");

regards,
Olafur

[Ólafur Gíslason]

Well, it seems there is a simple solution.

I went through all the posts here on this Forum  and used my trusted source Google.

I host the Html Placeholder in a ScrollView.

       <ScrollViewer Height="122" HorizontalAlignment="Left" Margin="41,66,0,0" 
            Name="scrollStoryboard"     VerticalAlignment="Top"         Width="514">
            <telerik:RadHtmlPlaceholder Name="radHtmlStoryboard" />
        </ScrollViewer>

Then on OnNavigatedTo event of my page I do a quick hide and show on the Placeholder and set the scolling and overflow properties.  I should be able to set these properties on the OnLoad event but it does not work.

            radHtmlStoryboard.Visibility = System.Windows.Visibility.Collapsed;
            radHtmlStoryboard.Visibility = System.Windows.Visibility.Visible;
            (radHtmlStoryboard.HtmlPresenter.Children[0] as HtmlElement).SetAttribute("scrolling", "no");
            (radHtmlStoryboard.HtmlPresenter.Children[0] as HtmlElement).SetAttribute("overflow", "visible");

And whenever I write something to the HtmlSource, I call the UpdateLayout followed by the ScrollToVerticalOffset on the ScrollView

                    htmlText = transcript .MessageText  + "<br/>";
                    radHtmlStoryboard.HtmlSource += htmlText;

                    radHtmlStoryboard.UpdateLayout();
                    scrollStoryboard.ScrollToVerticalOffset(radHtmlStoryboard.ActualHeight);
  

This works like a charm and scrolls to the bottom every time. The overflow property is needed if the output is too wide for the HtmlPlaceholder and forces a wrap on the HtmlPlaceholder and then a vertical scrollbar would appear.

regards,
Olafur

[Kiril Stanoev]

Hello Ólafur,

Thank you for sharing this workaround.

Best wishes,
Kiril Stanoev
the Telerik team

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