Steps to reproduce in designer for Qt 4.8.0
When I click one of the layout buttons above, it doesn't change the layout of the page QWidget, it changes the layout of the dialog even though I had explicitly selected the page.
Is this a bug in designer? Am I missing something? I really don't want to add the layouts programatically as that prevents me from being able to layout the pages in designer in the same .ui file
Clicking a widget page in the object tree brings that page to the top of the stack, but it does not select it.
In fact, it is not possible to select a widget page itself - only its child widgets can be selected (as well as, of course, the parent stacked-widget).
The easiest way to set a layout for a widget page is to:
Note that it is not possible to set a layout on a widget that does not have any child widgets.
(If there is a bug here, it is that the toolbar buttons should really be greyed-out when clicking on a widget page in the object tree that has no child widgets. When the stacked-widget arrows are used, the toolbar buttons are greyed-out correctly).