Thank you for the sample (ClientUIWPFNavApp1.zip - attached on soup soup's post on May 26, 2015).

I made a minor modification to UXPage1.xaml.cs by setting the URL of AxWMPLib.AxWindowsMediaPlayer to a media file which exist in my end.

from:

axWmp.URL = @"C:\Users\Public\Videos\Sample Videos\野生动物.wmv";

to:

axWmp.URL = @"C:\Windows\Media\tada.wav";

The result is (AllowsTransparency="True"): when user navigates to "ActiveX" page, I can hear that tada.wav is played. This proves that the ActiveX control works. It just can't be seen.

Next, I create another project which uses native WPF controls (without using ClientUI controls). Then set WindowStyle to None; and AllowsTransparency to True.

The result is similar. The ActiveX control works, but not visible.

In my opinion, it comes to a conclusion that enabling AllowsTransparency will causing ActiveX control becomes invisible. It isn't ClientUI bug since native WPF control show this behavior as well.

Please let me know if you have different thoughts.

Glad to hear that the CSS trick resolve the problem.

Should you need further assistance or run into any problems regarding our controls, feel free to post it into our forum. We would be happy to assist you again.

It is not possible for an ActiveX control to run inside of Silverlight.

However, it is possible to have an html page host both Silverlight and an ActiveX control and have these two communicate via javascript.

The step-by-step below shows what I did on my local end in order to replicate the reported problem.

1. Create Silverlight project using Intersoft ClientUI MVVM Application project template (.NET Framework 4 and Silverlight 5).
2. Add new item in Views folder by using Intersoft UXNavigationWindow item template.
3. Copy UXNavigationWindow.NavigatorStyle from the snippet code (from soup soup's post on May 15, 2015) and add it to my UXNavigationWindow

However, I was unable to reproduce the reported problem using these steps. For your information, I'm using VS 2012 and ClientUI 11.

Should you find anything that I might miss during my attempt to replicate the problem, please let me know.

From the snippet code, your WebDialogBox uses UseIFrame as its ContentMode. I made a minor change to ContentMode.aspx sample file of WebDialogBox by setting the WindowsHeaderHeight of WebDialogBox2; save the changes; then view the page in browser. When user click "Show DialogBox that uses IFrame" button, WebDialogBox2 will appear with title bar removed.

Is it possible that your WebDialogBox is integrated to WebDesktopManager (IntegratedToDesktopManager is enabled)? If yes, you can try to set the WindowHeaderHeight from the WebDesktopManager instance that host the WebDialogBox.

If this still doesn't help, could you please send me a simple sample of WebDialogBox that replicates the problem, so that I can assist you further?