App designer, making components visible

im having trouble turning on and off visiblity of a dropdown component and a button component

This error has come up for "switch expression must be a scalar or a character vector

app.SelectfeildDropDown.ValueChangedFcn

app.SelectfeildDropDown.Items

for

app.SelectfeildDropDown.Value

nothing happens we i change the value on the GUI

% Callbacks that handle component events

methods (Access = private)

% Value changed function: SelectfeildDropDown

function SelectfeildDropDownValueChanged(app, event)

switch(app.SelectfeildDropDown.DropDown.value)

case 'select'

case 'Tempreture'

app.MetrictoImperialButton.Visible

app.DropDown.Visible

case 'Length'

app.MetrictoImperialButton.Visible

app.DropDown.Visible

case 'Mass'

app.MetrictoImperialButton.Visible

app.DropDown.Visible

end

end

end

Answer 1

[Image Analyst]

You can't switch on the function name. You have to switch on the "Value" property, not the callback function's name, like:

switch app.SelectfeildDropDown.Value

Check spelling -- did you mean field instead of feild?

Then, I think you need to actually set the Visible property to something to show or hide it. So do something like

app.DropDown.Visible = 1; % 1 to show.  0 to hide.

Or maybe they use 'on' and 'off' instead of 1 and 0. They are inconsistent about that (at least in GUIDE they were). So if 1 and 0 don't work, try 'on' and 'off'

[MIchael Brennan]

Thanks I managed to work it out, it was supposed to be switch app.SelectionfeildDropDown.Value

But i also needed to toggle the visibility on and off

[Image Analyst]

I guess I must have been posting that same solution at the very same time you were figuring it out on your own. But glad it's fixed.

Answer 2

[MIchael Brennan]

This is what i wanted

[MIchael Brennan]

for case 'Length' & case 'Mass" they should be identical to case 'Tempreture