title: Qt Mac multiple menubars/modifiable menubar
body: <p>I have an application that shows multiple subpanels &amp; the client wants to show different menus for each subpanel.</p>
  
  <p>Mac apps can only have one menuBar per system window, apparently, and it's minimally modifiable (if at all.)  I need to remove/add or enable/disable menus on the menubar.</p>
  
  <p>I've thought about making each of the subpanels a system window and attaching a menubar to each, but I don't see any provision for switching to a window's menubar.  Besides, I suspect that doing so would create a state/positioning mess for the subpanels.</p>
  
  <p><strong>What I've Found</strong></p>
  
  <p>I've found that if I create the actions as children of the main window, I can add and remove them at will from the menus themselves.  So, I can modify the menu contents, but I can't modify the menubar contents.</p>
  
  <p>I've found I can also change the title of the menu to anything at any time.  So, if I clear the contents and set the title to an empty string, it has the apparent effect of removing the menu (although it's still there and still highlights).</p>
  
  <p>Barring another solution, have to do that, for now.</p>
  
  <p>Is this possible at all on Mac?  If I went down into Cocoa (don't know Cocoa), would I be able to maybe set up multiple menubars, or at least modify the menubar when the subpanel changes?</p>