Unmanaged DLL (exporting Dialog) + Class Library (DLL) + no Windows Style/Themes

Question

Hi,

I have a managed application TestApplication.exe in C# and Application.EnableVisualStyles() is allready called.

I have a Class Library MySharedCode.dll also in C# which uses [DLLImport()] to import some External dialogs out of an unmanaged dll.

Well, now I am using (add reference) MySharedCode.dll in my TestApplication.exe and call a function MyTestConfigDlg() out of it. TestClass.MyTestConfigDlg();

OK, everything works fine and I get my dialog, but the dialog has NO XP style/themes?

I just wanted to see if it's general problem with managed/unmanged modules, so I used the [DLLImport()] to call the same MyTestConfigDlg() dialog but this time directly in my TestApplication.exe! WOW! Worked as I expected. The Dialog was in XP Style/Themes!

so, anybody here who can help me out? FYI: I also tried (just for test) to call MessageBoxA() API call in my Class Library Dll which later called by my TestApplication.exe and the MessageBoxA() had also no Style/Themes!

Thanks in advance!

Answer 1

Usage of the Application.EnableVisualStyles() applies to certain windows controls such as ListBox, ListView, Menu, Buttons, to make it in line with the XP themes control from the start, if it was running on Vista and later, it would conform the controls to that style also. In short I do not know how do you mean the dialog has no XP/Themes support when invoked directly via the References, yet when you used DllImport keyword to import the function it worked, that is unusual. Usually the usage of DllImport is for unmanaged code API, but somehow it picked it up...I do recall that there was a bug with the .NET 1.1 framework in that if you called Application.EnableVisualStyles(), it failed to work, unless a call to Application.DoEvents() was invoked between enabling the Visual styles and instantiating a winforms, maybe in your case, when instantiating a dialog, perhaps that could solve it by calling Application.DoEvents(), other than that, I am out of ideas...

Hope this helps, Best regards, Tom.