I have a customer which as a Visual Basic Project in single instance mode with a wired presentation logic.
The main form contains a TabControl with mutliple TabPages. If I click on TabPageA another form is shown in front of the Form and resized to have the same size as the TabPage.
If I click on TabPageB the first form is hidden and another form is displayed. So basically for the user it looks like you have a TabControl with different TabPages which is not the case.
I tried converting the Forms to UserControls and put them inside the TabPage, but, thanks to the SingleInstance app, this would take a whole lot of refactoring. I tried it but eventually gave up because of many many runtime errors and I don't want to put any more effort in this.
My Ideam was that, at runtime, I could add the forms to the TabPages and let them act like UserControls, is this even possible?