Windows 10 OS Themes and VCL Styles

[David Hoyle 68]

I've just moved my development to a new Windows 10 machine and wondered why my VCL applications do not use the Windows 10 OS theme that I've selected, i.e. Dark Theme.

Now I understand that there are specific VCL themes you can select from the project options for an application and some of those are Windows 10 related however in the application I'm building I was wanting to provide a choice to the user of either an unthemed VCL application which uses the Windows 10 OS theme or one of the VCL themes but my current experiments suggest that an unthemed VCL application does not use the OS theme.

Am I missing something?

[PeterBelow 238]

Go to the project options dialog, Application -> Manifest node. Do you have the "enable run-time themes" checkbox checked?  (Caption may be different, i'm extrapolating from a german IDE here). If you use a custom manifest for the application it needs to contain the equivalent entry for that.

[David Hoyle 68]

@PeterBelow Yes my application has "Enable Run-time Themes" checked but by default uses the "Windows" theme. In a test application this scenario shows as TStyleManager.Enabled = False.

I'm guessing that there is a particular set of circumstances that I need to configure to get this to work?

[Uwe Raabe 2057]

Enable Runtime Themes and using VCL Styles are different things. The former is enabled in the Application Manifest settings while the latter is configured in Application Appearance. A Default Style setting of Windows should use the OS Style. Note that both require to Enable Runtime Themes.

[David Hoyle 68]

@Uwe Raabe Thanks. I had not made that distinction before. I'll experiment with a test application tonight to see where I get.