App Designer - ListBox Tooltip for too long entries not there any more in 2019b

I made an app with App Designer in Matlab 2018a. Now I swichtched to 2019b.

In my app are a lot of list boxes with entries that are too long for showing it completely. In 2018a too long entries ended with "..." and if you hover over it, a tooltip appeared, that showed the full entry text.

Now in 2019b this is not the case any more. I tried all the options in the graphic version of the app designer, but could not solve the problem. I want to avoid useless scrolling to the right and left. So I want the tooltips back.

Is there any way to get a tooltip in 2019b , like in the 2018a app designer?

Thank you!

2018a (too long entries with three dots, and if you hover over an entry, you see the full text):

2019b (text just cut, but therefore the scrollbar is there, hovering not possible):

Answer 1

[Cameron B]

How did you originally get the tooltip to specify only the line you're hovering on in 2018a? The only way I know is to use mouse wheel movement callbacks, but maybe there's another method. Every time I use tooltip it just shows the entire contents of the tooltip cell array.

[Tim P]

This was there by default.

I just added a ListBox that is not wide enough for the content. The three dots were there automatically, and the mouseover was also working automatically.

Full code of the ".mlapp"-File. I am using for this screenshots above the same code, but just in 2018a and 2019b.

classdef TooltipListProblemApp2018 < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure      matlab.ui.Figure
        ListBoxLabel  matlab.ui.control.Label
        ListBox       matlab.ui.control.ListBox
    end

    methods (Access = private)

        % Code that executes after component creation
        function startupFcn(app)
            

        end
    end

    % App initialization and construction
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)

            % Create UIFigure
            app.UIFigure = uifigure;
            app.UIFigure.Position = [100 100 640 480];
            app.UIFigure.Name = 'UI Figure';

            % Create ListBoxLabel
            app.ListBoxLabel = uilabel(app.UIFigure);
            app.ListBoxLabel.HorizontalAlignment = 'right';
            app.ListBoxLabel.Position = [81 385 48 22];
            app.ListBoxLabel.Text = 'List Box';

            % Create ListBox
            app.ListBox = uilistbox(app.UIFigure);
            app.ListBox.Items = {'Very Long Item 1', 'Very Long Item 2', 'Very Long Item 3', 'Very Long Item 4'};
            app.ListBox.Position = [144 335 79 74];
            app.ListBox.Value = 'Very Long Item 1';
        end
    end

    methods (Access = public)

        % Construct app
        function app = TooltipListProblemApp2018

            % Create and configure components
            createComponents(app)

            % Register the app with App Designer
            registerApp(app, app.UIFigure)

            % Execute the startup function
            runStartupFcn(app, @startupFcn)

            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

[Cameron B]

I'm not even sure how you got the tooltip to work on 2018a if this was your code. The relevant part of mine is:

            % Create ListBox
            app.ListBox = uilistbox(app.UIFigure);
            app.ListBox.Items = {'Very Long Name 1', 'Very Long Name 2', 'Very Long Name 3', 'Very Long Name 4'};
            app.ListBox.Tooltip = {'ans 1'; 'ans 2'; 'ans 3'; 'ans 4'};
            app.ListBox.Position = [126 263 90 74];
            app.ListBox.Value = 'Very Long Name 1';

and regardless of which item I hover over, it still reads the entire contents of app.ListBox.Tooltip. I suppose a quick and imperfect way to get around this is to make the following callback:

             % Value changed function: ListBox
        function ListBoxValueChanged(app, event)
            value = app.ListBox.Value;
            app.ListBox.Tooltip = value;
        end

I'm not a fan of this method though. It requires the user to select a new item in the list box just to see what the contents are and even then, the user must move the mouse outside the listbox then back in for the tooltip string to update. I suppose it does have the added benefit of showing multiple samples if you have multiselect on, but I would still look for another way. The MATLAB documentation gives this:

Tooltip, specified as a character vector, cell array of character vectors, string array, or 1-D categorical array. Use this property to display a message when the user hovers the pointer over the component at run time. The tooltip displays even when the component is disabled. To display multiple lines of text, specify a cell array of character vectors or a string array. Each element in the array becomes a separate line of text. If you specify this property as a categorical array, MATLAB uses the values in the array, not the full set of categories.

So I'm not sure if you can make the categorical array do that for you.

[Tim P]

Hello,

thanks for this idea! It kind of works, but as you mentioned it is a little bit unhandy.

In my app I have long lists and don't want the user to klick everytime while scrolling through the list.

The code above is my full .mlapp-File that I used for the screenshots above. In 2018a this tooltip for too long contents appeared automatically. My whole app depends on that feature, since I don't have much space for the Lists, and the List Entries are pretty long. So I can not understand, why a feature that was there in 2018a is not any more there in 2019b. Just one tick in the App Designer GUI would be enough that says something like "Crop long entries and show full content if mouseover".

It seems that I have to switch to tables instead of lists, there is this function still included. But there I have the problem, that the standard tooltip is sometimes hidden by other objects, which drives me crazy (see here).

I don't really understand what the documentation means and how this could help. What is a categorical array, and would this give me the tooltip for only the mouseover list entry?

[Cameron B]

Do you need to be able to select multiple items at once? If not, you can use the uidropdown feature instead. This might be easier than all other suggestions which may include java or other undocumented matlab work.

[Tim P]

No I don't need multiple selection. But the tooltip should appear also if the item is not selected.

What I need for my app: I have a list loaded, and every entry corresponding to a measurement data file. The App plots all of the measurements. If I klick on one measurement in the list, it shows in a table the details of this measurement, such as Date, used Settings, Equipment, etc... But the names of the measurements are pretty long, and for example if I have measurments of the same sample with different settings, the file-names start the same, but end different. So in 2018a it was possible to see the full file-name by hovering over the file name. As seen in the screenshot above (3 dots and tooltip if it is hovered).

By uiDropDown you mean that I should use a drop down menu? Sadly not possible. I need to see all the data names. They are also used as color legend for the plots...