MATLAB: App Designer: Keeping some components fixed size while resizing the rest

appdesignerautoresizechildrenguiMATLABresizesizechangedfcn

I am designing an app with a plot and a control panel. I would like the plot to resize and the panel to have a fixed horizontal width when the user resizes the app window. Right now the behavior is such that both the plot and the panel both resize in x and y dimensions.

How can I accomplish this?

Best Answer

1. Set the "AutoResizeChildren" property to 'off' on the parent of the uipanel which needs to be of fixed width and write a SizeChangedFcn for it instead.

Write callback functions with the "SizeChangedFcn" property that would make the uipanel grows taller and make the axes grows wider and taller when the app is resized.

2. Leave AutoResizeChildren to 'on' on the uipanel (and any containers inside it), so that when the uipanel is made taller (via the SizeChangedFcn written above), the things inside the uipanel get auto resized.

Related Solutions

MATLAB: ‘AutoResizeChildren’ App designer warning

In short:

The warning is displayed because you have both the "Resize components when app is resized" option checked and have written a SizeChangedFcn callback on a container. These two things are mutually exclusive, you must choose one or the other. If you have both, the SizeChangedFcn callback will be ignored.

More details...

AutoResizeChildren is a property that corresponds to the "Resize components when app is resized" checkbox in the "uifigure properties" panel (to see this panel, click on the edge of the uifigure, this panel is by default in the lower right side).

Code-wise, when this checkbox is checked, the AutoResizeChildren is set to 'on' on the uifigure and on all the containers inside that app.
Behavior-wise, when the checkbox is checked, once you run the app and then resize it, components inside your app (and inside all the containers) will be resized based on some heuristics.

Now, containers also have a SizeChangedFcn property that allows you to specify how components should be resized when the container itself is resized.

You should either choose to have the components resized based on the heuristics (i.e. check that checkbox), or write SizeChangedFcn callbacks on the containers, but not both. If you have written a SizeChangedFcn function on any container inside that app or on the uifigure, and checked the AutoResizeChildren option, the SizeChangedFcn function(s) will be ignored and components will be resized based on the heuristics. The warning tells you that the SizeChangedFcn will be ignored.

If you want the SizeChangedFcn callback(s) to work, you must uncheck the "Resize components when app is resized" checkbox.

Note: Even if you have removed the content of a SizeChangedFcn callback, the callback is still defined. If you want to use AutoResizeChildren behavior, you must remove the SizeChangedFcn callback altogether (right click, delete the callback).

MATLAB: App Designer How to “StartUp” within the App

(1) Two possibilities to reset your app to its default state:

https://www.mathworks.com/matlabcentral/answers/489003-reset-or-clear-property-values-in-app-designer#comment_763148

https://www.mathworks.com/matlabcentral/answers/489003-reset-or-clear-property-values-in-app-designer#answer_399598

I prefer the first. A simple example using a function called resetComponents:

classdef app1 < matlab.apps.AppBase
    % Properties that correspond to app components
    properties (Access = public)
        UIFigure        matlab.ui.Figure
        EditFieldLabel  matlab.ui.control.Label
        EditField       matlab.ui.control.EditField
        Button          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 EditFieldLabel

            app.EditFieldLabel = uilabel(app.UIFigure);
            app.EditFieldLabel.HorizontalAlignment = 'right';
            app.EditFieldLabel.Position = [382 282 56 22];
            app.EditFieldLabel.Text = 'Edit Field';
            % Create EditField

            app.EditField = uieditfield(app.UIFigure, 'text');
            app.EditField.Position = [453 282 100 22];
            % Create Button

            app.Button = uibutton(app.UIFigure, 'push');
            app.Button.Position = [129 282 100 22];
            app.Button.Text = 'Reset';
            app.Button.ButtonPushedFcn = @app.resetButtonCallback;
            % Show the figure after all components are created
            app.UIFigure.Visible = 'on';
        end
        
        function resetComponents(app)
            % Create EditFieldLabel
            app.EditFieldLabel = uilabel(app.UIFigure);
            app.EditFieldLabel.HorizontalAlignment = 'right';
            app.EditFieldLabel.Position = [382 282 56 22];
            app.EditFieldLabel.Text = 'Edit Field';
            % Create EditField
            app.EditField = uieditfield(app.UIFigure, 'text');
            app.EditField.Position = [453 282 100 22];
            % Create Button
            app.Button = uibutton(app.UIFigure, 'push');
            app.Button.Position = [129 282 100 22];
            app.Button.Text = 'Reset';
            app.Button.ButtonPushedFcn = @app.resetButtonCallback;
            
            % Or, alternatively, instead of redefining each component, just figure out all
            % properties which could be changed by the user and reset them to their
            % defaults:
            %

            % app.EditField.Value = '';
            %
            % Simpler here, but takes more work for more complicated apps.
        end
        
        function resetButtonCallback(app, ~, ~)
            resetComponents(app);
        end
    end
    % App creation and deletion
    methods (Access = public)
        % Construct app
        function app = app1
            % 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

(2) You can access a callback function if you have access to an instance of the app and you are calling from a location allowed by the function's Access attribute (e.g. Public, Private, etc).

Example 1: You cannot call a callback function from within a static method, because the static method does not have access to an instance of the app.

Example 2: You cannot call a callback function externally if its Access attribute is Private.

Best Answer

Related Solutions

MATLAB: ‘AutoResizeChildren’ App designer warning

MATLAB: App Designer How to “StartUp” within the App

Related Question