Creating empty ui control component

When using appdesigner, I want to initialize a property as an array of labels and text area

properties (Access = private)
    comp_ui_obj
end
    
function startupFcn(app)
    app.comp_ui_obj(1) = app.CompLabel;
    % 2..n assignments here
end

The problem is that the declaration of comp_ui_obj is by default double. Because of this app.comp_ui_obj(1) will contain a double instead of a matlab.ui.control object.

So, it seems that app.comp_ui_obj needs to be initialized as an empty matlab.ui.control object before the assignment.

With some classes, the empty function can be used for this (ex: uint8.empty). However, matlab.ui.control.empty does not work.

So, how do we initialize an empty ui control in appdesigner? How do we initialize a vector of empty elements?

[Cris LaPierre]

Could you provide more detail on why you are wanting to do this? What is the need driving this workflow?

Answer 1

[Cris LaPierre]

Try setting your property to an empty Label class using the following

comp_ui_obj = matlab.ui.control.Label.empty

[Bruno Pilon]

This is exactly what I was looking for. I was missing the capital L of Label. Thank you!

Answer 2

[Bruno Pilon]

I found one way to initialize the ui control variable:

dummy_obj = uilabel(app.UIFigure);

app.comp_ui_obj = repelem(dummy_obj,nb_of_objects);

Then, the assignments work as app.comp_ui_obj already contains ui objects.