Why is TabGroup.S​electedTab​.Title giving me the wrong title?

I am simulating a processing system with groups of equipment broken up into different 'workcenters', where each workcenter is allowed a different operating schedule. In an app, built in app designer, each workcenter's equipment are displayed in a table, and each equipment table is displayed on a different tab of a single tab group.

If a user chooses to add equipment to the system, it is essential that I know what workcenter to add it to.

Problem: I have been using the TabGroup.SelectedTab.Title property to do this, but in 2023b Update 7, I noticed when you query this property, it does not reliably return the title of the tab that is actually selected.

I reported this to MathWorks Technical Support, and the person I spoke to said this issue had not been reported yet.

Any ideas?

Kind regards,

David

1) mouse location? but this method would depend on the size and shape of the title text.

I'll likely need to rearrange my content into different containers, but it will take time.

Answer 1

[David Meissner]

properties (Access = private)
    Tab2      % Create premade property names with common format.
    Tab3
    Label2
    Label3
    idx = 1   % My app starts with just one tab, and that user adds more.
end

methods (Access = private)
    function getInfo(app, ~, evt)
      app.TitleEditField.Value = evt.Source.Title;      % Display correct title.
      app.NumberEditField.Value = evt.Source.UserData;  % Display correct index.
      app.idx = evt.Source.UserData;                    % Store for later.
    end
end

methods (Access = public)
    function createTab(app)
      n = length(app.TabGroup.Children) + 1; % Tab number
      if n > 3; uialert(app.UIFigure, "No more tabs.","Alert"); return; end % For this example
      ns = num2str(n);
    
      % Create tab with the premade callback.
      app.("Tab" + ns) = uitab(app.TabGroup, 'Title', "Tab" + ns,...
        'ButtonDownFcn', @(src, evt) app.getInfo(src, evt), 'UserData', n);
    
      % Create some type of data container. 
      app.("Label" + ns) = uilabel(app.("Tab" + ns),...
        "Text", ns, "Position", app.Label1.Position, "FontSize", 48);
    end
end

% Callbacks that handle component events
methods (Access = private)

    % Code that executes after component creation
    function startupFcn(app)
      app.TitleEditField.Value = app.TabGroup.SelectedTab.Title; % First tab.
      % Set callback and userdata for the first tab's buttondown function.
      app.TabGroup.Children(1).ButtonDownFcn = @(src, evt) app.getInfo(src, evt);
      app.TabGroup.Children(1).UserData = 1;
    end
    
    % Button pushed function: MakeTabButton
    function MakeTabButtonPushed(app, event)
      createTab(app)
    end
    
    % Button pushed function: getdataButton
    function getdataButtonPushed(app, event)
      % Get data from the chosen container.
      app.DataEditField.Value = app.TabGroup.Children(app.idx).Children(1).Text;
    end
end

This technique might work, but the idea is basically store an index associated with each tab in the tab's UserData (when its created) and then grab that from the event info when the user selects a tab. Then use that index to grab the right tab to get into the data stored on that tab. This method does not require strcmp to find the right tab. Note the first tab's callback is specified in the startupFcn.

Final results: TBD