"Unrecognized method, property, or field 'Type' for class 'matlab.ui​.control.W​ebComponen​t'."

In App Designer (MATLAB R2024a, Windows 10 Pro, 64-bit) I have a tab (app.tabFiles) that has a few ui components on it. When I query the Type property on all of them at once, I get the following error:

tf = strcmp({app.tabFiles.Children.Type}, 'uistatebutton') ; % This works fine with 7 other tabs, panels, etc

"Unrecognized method, property, or field 'Type' for class 'matlab.ui.control.WebComponent'."

However, if I query the Type of the components individually, each happily returns its Type. Huh?

I should mention, there are 13 components visible on the tab and 13 listed in the Component Browser. However, the tab has 14 Children - the extra child is the label (set to empty string) on a uieditfield component - but all respond as expected to the individual Type request.

Any idea what would cause that exception to be thrown? And how to avoid it?

Answer 1

[Fangjun Jiang]

I think app.tabFiles.Children is an array of handles. Try tf = strcmp(get(app.tabFiles.Children,'Type'), 'uistatebutton')

[Dave Watson]

Yes, thank you, that works. However, it should be equivalent to what I did and my approach works on other UI components with Children, with that one exception. Mysteries of MATLAB! Thanks, again.

[Fangjun Jiang]

close all;plot(1:3);

obj=findobj(0)

obj = 
  4x1 graphics array:

  Root
  Figure    (1)
  Axes
  Line

obj(1).Type

ans = 'root'

get(obj,'Type')

ans = 4x1 cell array
    {'root'  }
    {'figure'}
    {'axes'  }
    {'line'  }

obj.Type

Unrecognized method, property, or field 'Type' for class 'matlab.graphics.Graphics'.