Hi Thilo,

this is an unfortunate limitation of the current PB theme functionality.

The corner resize grip John mentioned can be implemented in "pure" PB:
Simply add a small picture control and add to it a user event, choosing the Event-ID pbm_nchittest in the dropdown. Then simply return the value 17 ( = HTBOTTOMRIGHT) and this picture control will work as a resize handle. I do this using themes and it works. You still have to ensure that the control stays in the corner, I do this using the pfc resize service.

In theory it could also be used to add invisible areas to the left, lower and right window borders in order to increase the area you need to hit with the mouse. I've played around for it but couldn't get it to work for anything other than HTBOTTOMRIGHT though. For other possible values see:

https://docs.microsoft.com/en-us/windows/win32/inputdev/wm-nchittest

Greetings, Thilo -

If your application uses an ancestor window object, one possible alternative would be to add a resize "grip" to the lower-right corner of the ancestor window, as shown in the close-up below:

Like you, I find ultra-thin resizable window borders difficult and frustrating to use. A resize grip makes resizing much easier.

I have a sample program in CodeXchange that includes this functionality, if you're interested:

https://community.appeon.com/index.php/codeexchange/powerbuilder/265-pfc-resizing-example-application

The sample program primarily illustrates a proposed methodology for implementing complex resizing scenarios when using the Resize service included in the PowerBuilder Foundation Class (PFC) framework. The addition of the grip control to a window does not require using the PFC. It does require use of a small user object (the grip control), a small about of code in several window events and three Windows API functions (GetCapture, SetCapture and ReleaseCapture).

A companion tutorial includes helpful information about implementing the resize grip:

https://community.appeon.com/index.php/articles-blogs/tutorials-articles/2-powerbuilder/315-the-pfc-resize-service-complex-resizing-via-a-simple-methodology

I need to mention that I have not tried using this resize grip control in a "themed" app, so I can't say how well it looks and/or works with Themes. If you decide to try it, I'd be very interested to hear back from you how well it works.

I hope you find this helpful.

Best regards, John

Hi, did Someone found a better Solution then the "Grip"?
@Thilo Mack, how did you increase the size of the border? 

The "Grip" is hiding in the Main Window... and in Response Windows it rezised itself and not the Window....

To be honest, I think that the "Grip" is only an emergency solution anyway, the edges of the windows must be grippable normally...

I'm grateful for every tip

Best regards, Steffen