No horizontal scrollbar on on UITable in App Designer

I am working on an app in AppDesigner. One of the features requires the ability to import a large table (CSV or XLSX) with an unknown size (~50-60 columns). The app starts with an empty table and the user selects one to view.

When the user imports the table, a vertical scrollbar is automatically generated and the user can scroll down all the rows. However, the horizontal scrollbar is not generated even though the table extends off the panel significantly. See attached image.

If I specify a size for the initial empty table then a horizontal scroll bar will appear, but it will not adjust to the correct size once the user imports a new table. Since the user table size is unknown, this will not work.

I only see this problem in the AppDesigner. Generate a UIFigure and UITable using the MATLAB command line, a scroll appears and adjusts to size without issue. However, this functionality is part of a larger app, and I would prefer to work inside the AppDesigner.

[Russell Shomberg]

A workaround I found is to to delete the UITable and create a new one. This works, but also means none of the settings specified by the app designer carry over so not ideal.

[Mahdi Khosravi]

Hello Russell,

Did you solve this problem? It seems that this problem is only for Matlab R2022b. I checked it on R2021b and R2019b with the same code and I did not see this problem. Please inform us here if you could solve it in R2022b.

Thank you

[Staffan Neth]

Still no official answer from Mathworks on this, or is there a bug report?

[Adam Danz]

If you are experiencing this problem, it would be helpful to

1. attach your app and any additional required files
2. provide step-by-step instructions to recreate the problem starting with opening the app.
3. tell us what MATLAB Release you're using (see the ver or version functions)

Alternatively, contact tech support to report a bug and provide the information above.

Answer 1

[Alexandre]

Thanks for reporting this bug!

Starting in MATLAB R2023a, AppDesigner does not experience this issue.

As an example under startupFcn in AppDesigner:

function startupFcn(app)
    T = readtable("patients.xls");
    app.UITable.Data = T;
end

You will now see that MATLAB properly includes a horizontal bar.

For earlier versions of MATLAB, please look at the clever workarounds below provided by our MATLAB Community.

Answer 2

[Josh Kahn]

Hi,

This is a known issue in R2022b. The suggested workaround for now is to reset the row names after adding data to your table:

% Add data to your table
app.UITable.Data = myData;

% Redraw the table and toggle the row names to numbered then back to blank.
drawnow;
app.UITable.RowName = 'numbered';
drawnow;
app.UITable.RowName = '';

Regards,

Josh

[Arnab Samaddar-Chaudhuri]

This works best

Answer 3

[Arash Moshkforoush]

I had the same problem, but only when I tried using the app as a webapp.

What worked for me was that if I increase the number of columns to a large number in the ColumnName section of the UITable (in my case 20 columns; which is larger than the number of columns of the actual table), once a new table is loaded, the scrollbar is automatically generated.

Another possible workaround is to increase the ColumnWidth such that the initial table is wider than the alloted space.

Hope this helps

[Staffan Neth]

I tried you suggested workaround with ColumnWidth, and it made the scrollbar appear, but scrollbar is still not updated when the table is updated, so the scrollbar is still limited to the initial width, which is not enough.

Answer 4

[Mathijs Werkman]

Hello, I had the same issue.

Affter a lot of trying got it to work by:

• Create startupFcn

Startup Tasks and Input Arguments in App Designer - MATLAB & Simulink - MathWorks Benelux

• Creating a larger table at startupFcn: only changing columnnames is suficient.

tmp(1:1000) = {''};

app.UITable.ColumnName = tmp;

• Before putting the actual data in the table, empty it first, and set RowName:

app.UITable.Data = [];

app.UITable.ColumnName = [];

drawnow;

app.UITable.RowName = ' '; % it has to be a character, cannot be empty ''

• then update the table

app.UITable.Data = <your table data>;

app.UITable.ColumnName = <your columnnames>;

drawnow;