I find it's hard to rat-wrestle your way to a GUI that adapts nicely to different window sizes, resolutions, etc. Xcode probably comes the closest but I haven't tried it in years. I know there are purists who think "well, it's a VISUAL interface so you have to lay it out VISUALLY!" but this is actually trickier than you might think when you have to render the UI in a different context from when you created it.

I've found it easier just to do declarative layout. Tcl/Tk does this real well, and has since the early/mid 90s. I know that Tk uses imperative commands to build out the UI scene graph but it's effectively declarative. Tcl/Tk is pretty much VB done Unix style.