Practical way to have multiple "drawrectangle" and work with them

I have an image displayed in an axes. The user should draw multiple rectangles using drawrectangle (command started via menu command in a GUI). When the user decides that there are enough recangles, he will start the tracking algorithm which will track the content of every rectangle he has drawn.

I am looking for the easiest way to work with these rectangles. Each rectangle has a Matlab-built-in context menu, that allows to delete or adjust the rectangle. So I need some sort of a dynamic list of rectangles that also react to the interactions with the context menu.

Here is the principle that generates a cell array of rectangles, but of course, it is not updated when the user interacts with the context menu. I am looking for a better way to generate and update this list of rectangles. Thank you for your help!!

% User adds a rectangle
if isempty(track_rectangles) %first time a rectangle is selected
	track_rectangles=cell(0)
end
track_rectangles(end+1)={drawrectangle(gca)}

Answer 1

[William Thielicke]

Ok, I found something in the help:

hfhs = findobj(gca, 'Type', 'images.roi.Rectangle')

Calling this just before starting the tracking will give you a list of all rectangles that have been drawn.