VB6 Menu Problem
Posted on 2003-10-29
In my VB6 MDI application, the MDI form has quite a few menus. There are 10 main menus, each with up to 8 or so submenus. In several places, some of those submenus contain submenus of their own. So at most the menus nest to three levels.
When the user selects a menu item, I disable certain other menu items that can't be available while the user is "in" the menu (most of the menus open a child form). When the user closes from the form involved, I enable the menus I disabled. It can get quite complex because when one menu is entered, several get disabled, but there are others that remain available. If the user selects one of those, I disable the appropriate items for that selection, taking into account whether they have been disabled by a previous selection. I accomplish this with a dynamic array that keeps track of what menus are disabled by what other menus. It all works really well.
However I have a problem. Sometimes I run into a runtime error because you can't disable all of the visible submenus for a menu. It makes sense, of course, otherwise you could choose a menu and see all disabled options, which isn't good form.
My latest solution is to model the menu structure completely in an array. I perform the changes on the array when enabling/disabling menus, then check for the error situation and disable the parent menu if all of its submenus are disabled. I then have to carefully apply the changes from the array to the actual menus on the form. The best I can do has me looping through all those menus 3 times. This is because I can't disable all submenus and then disable the parent menu. I have to do the parent(s) first. All in all, it is too complex, slow and isn't satisfactory.
1. Anyone had this problem before? Is there a "standard" solution to this I have never seen?
2. Should I go entirely another way? - I've been toying with generating the entire menu structure dynamically at runtime - that way, instead of enabling/disabling menu items, I can re-generate only the available ones. Doesn't sound very GUI-compliant, though.
3. Anyone know of a robust active-x menu control that doesn't have this limitation? (this is a commercial app I'm writing, the component has to be tried and tested).