A more supported way of re-using ui elements is by building custom component containers and adding them to your app: https://www.mathworks.com/help/matlab/developing-custom-ui-component-classes.html
That being said, you can subclass from apps built in App Designer, though your subclass needs to be in a ".m" file rather than a ".mlapp" file and can't itself be edited in App Designer. These subclass then unlock many more OOP design patterns. Note that there's no easy way to remove the app.UIFigure.Visible = 'on'; from the end of the superclass constructor, so be careful using this to change visual elements on construction.
subclass.m:
classdef subclass < superclass
methods
function app = subclass
app.SuperclassButton.Text = 'Subclass';
end
end
end
superclass.mlapp:
classdef superclass < matlab.apps.AppBase
% Properties that correspond to app components
properties (Access = public)
UIFigure matlab.ui.Figure
SuperclassButton matlab.ui.control.Button
end
% Component initialization
methods (Access = private)
% Create UIFigure and components
function createComponents(app)
% Create UIFigure and hide until all components are created
app.UIFigure = uifigure('Visible', 'off');
app.UIFigure.Position = [100 100 640 480];
app.UIFigure.Name = 'UI Figure';
% Create SuperclassButton
app.SuperclassButton = uibutton(app.UIFigure, 'push');
app.SuperclassButton.Position = [261 278 100 22];
app.SuperclassButton.Text = 'Superclass';
% Show the figure after all components are created
app.UIFigure.Visible = 'on';
end
end
% App creation and deletion
methods (Access = public)
% Construct app
function app = superclass
% Create UIFigure and components
createComponents(app)
% Register the app with App Designer
registerApp(app, app.UIFigure)
if nargout == 0
clear app
end
end
% Code that executes before app deletion
function delete(app)
% Delete UIFigure when app is deleted
delete(app.UIFigure)
end
end
end
