Send value in callback

Hi,

I want to have a Switch1 to change Text1 and Switch2 to change Text2 etc. I came up with the following code:

% function to change the text
function ChangeText(value, number)
    switch value
        case 'On'
            app.(['Text' number]).Value = 'Hi';
        case 'Off'
            app.(['Text' number]).Value = 'Bye';
    end
end

% callback for switch 1
function Switch1ValueChanged(app, event)
    value = app.Switch1.Value;
    app.ChangeText(value, '1')
end

% callback for switch 2
function Switch2ValueChanged(app, event)
    value = app.Switch2.Value
    app.ChangeText(value, '2')
end

This way the lines of code is reduced because the ChangeTex function is not in every callback. Still I would like to have less code. Is it possible to have one callback with the code of the ChangeText function, that can be called by all the switches and change the text paired with the switch? So one callback that causes a switch in switch n to change text n.

Already thankfull for the reply!

Answer 1

[Walter Roberson]

https://www.mathworks.com/help/matlab/creating_guis/write-callbacks-for-gui-in-app-designer.html#mw_54ae4804-091b-4168-a240-3defb0bc2ceb shows how to share callbacks.

I recommend that you follow the section immediately after that to create your own callback. Custom callbacks accept app, src, and event. src will be the handle to the object that triggered the callback. You can have stored information within the object, such UserData, which could be the name of the field that should be updated.

[Tim Reddering]

Can you maybe help me with an example for the case I described above? I do not understand how to work with the custom callbacks. Can I use the src (handle) to find the switch name? Or how do I use the handle?

[Walter Roberson]

function SwitchValueChanged(app, src, event)
  value = src.Value;
  app.ChangeText(value, src.UserData)
end

Having set app.Switch1.UserData to '1', app.Switch2.UserData to '2' and so on