Just a headache that took me several hours to understand and might save somebody some time.
I was adding in code GroupBoxes and was seeing the strange behaviour that the line surrounding the GroupBoxes was going through their title (as if the title was with a “strikeout” font style), as shown in the attached picture. As I discovered, this comes from my setting to GroupBox background color to Color.Transparent. This, obviously, makes transparent the background color of the “label” forming the GroupBox title, letting the surrounding line underneath show up in the “surface”.
The workaround is of course to not set the bkg color to transparent… Unless it is fixed so that the title bkg color does not follow the whole groupbox color. In fact I don’t know what the correct setting would be.
The groupbox in Wisej is composed of a widget container, an inner frame for the border, a checkbox (the label) and a collapse button. The problem is that the label (checkbox) shouldn’t have a transparent background when overlapping the frame (some themes may have the label above the frame). Internally, the label (a checkbox widget) automatically inherits the color of the groupbox and the groupbox automatically inherits the color of the parent. It’s done like that to create the broken line at the top. We couldn’t use the “frameset” element because of the checkbox and because it’s hard to style properly – it doesn’t support css consistently.