MATLAB: In GUI, is there a function where I can initialize variables using handles that I can then pass on to all CreateFcn items

Question

OK, so I am new to GUI and am using the GUIDE feature. I created a complicated UI with lots of popout menus, sliders, etc. I wanted a bunch of variables to be readily accessible to the CreateFcn functions of all the items. I tried OpeningFcn but it looks like all the CreateFcn's are run before the OpeningFcn. I have the option of just declaring all my variables using handles in the popoutmenu that runs first. But is there no other alternative to this? I would ideally like a function to initialize all my required variables that runs first before creating any functions. Or at least, let me know if there is a way we can determine which menu item runs first. It looks like by default, the item you created last will run first. Thank you!

Answer 1

It is correct that the handles structure does not exist until after all of the CreateFcns have run.

Also, the order of running the CreateFcns is not completely defined: it is whichever one happens to occur first in the .fig file. The figure CreateFcn will be the first one for the figure, but if you have multiple items at the same level then you do not know which will get run first.

So you should probably have your figure CreateFcn build the variables and store them, perhaps using setappdata against the figure. (Using setappdata allows you to retrieve only the portions that you need for any one function.)