Enable/disable dropdowns when checkbox checked/unchecked in MATLAB2019A app designer

I want to disable the given dropdown if the checkbox is selected and enable it once checkbox is unchecked.

How should be the code?

Answer 1

[Kojiro Saito]

First, add ValueChangedFcn callback from app.CheckBox.

Then, define CheckBoxValueChanged function as the follows.s

% Value changed function: CheckBox
function CheckBoxValueChanged(app, event)
    value = app.CheckBox.Value;
    if value == true
        % If checkbox is checked, make dropdown disable
        app.DropDown.Enable = false;
    else
        % If checkbox is unchcked, make dropdown enable
        app.DropDown.Enable = true;
    end
end

Here is a screenshot.

[Paolo Volpe]

Hello there,

I tried to make the same example you did and it doesn't work. Any alternative solutions?

Error: Invalid expression. Check for missing multiplication operator, missing or unbalanced delimiters, or other syntax error. To construct matrices, use brackets instead of parentheses.

[Kojiro Saito]

@Paolo Volpe

Possibly, the syntax might be uncomplete . Could you show your callback function?

[Paolo Volpe]

@Kojiro Saito I just made the same passages you made in the script. I show you my steps:

1. I created a new APP Designer script
2. I added the checkBox and the DropDown icon
3. I added the callbacks
4. Here you find the code I put in the callbacks

% Value changed function: CheckBox
function CheckBoxValueChanged(app, event)
value = app.CheckBox.Value;

if value == true
    
    app.DropDown.Enable = false;
else
    
    app.DropDown.Enable = true;
end

end

[Kojiro Saito]

@Paolo Volpe

Do app.Checkbox and app.DropDown match the existing components?

In my previous answer, there are app.Checkbox and app.DropDown under app.UIFigure.

How do your components look like?

[Paolo Volpe]

This is how they look like

And this is the resulting error:

[Kojiro Saito]

@Paolo Volpe

OK, I found the reason.

Please delete the "end" in the last line. This occurs syntax error.

[Paolo Volpe]

Thank you, I didn't notice the end of the function

[Paolo Volpe]

I have another question @Kojiro Saito.

If I want to save my output file from the APP designer which function can I use? I didn't find nothing correlated to my question on the web. Thank you

[Kojiro Saito]

You can use save (as .mat file), writetable (as .csv or .txt, .xlsx) and so on.

For detail, please read this document (Export Function).

Also, with uiputfile, you can specify the file destination.