Restricting app slider values

Is there a way to restrict the values a slider in an app can take? I want to define an array of increasing numbers and have that be all the values the slider is allowed to take as I move it and NOT take on any other values. So for example if the first two values in my array are 1.23 and 2.45, I want the slider two start at 1.23 and when I move it to the right, it should go to 2.45 and NOT 1.4 or anything like that.

Thanks in advance!

Answer 1

[Cris LaPierre]

Is the spacing between values uniform? If so, you can set the step property.

If not, I think you would have to have your callback function process the slider value and set it to the predetermined value that is closest.

% Assume this is the slider value
value = 2.1;
% Assume this is the list of values you want the slider to take
myVals = [1.23 2.45 3.76 4.01];
% find the closest value
[~,ind] = min(abs(myVals-value))

ind = 2

valAct = myVals(ind)

valAct = 2.4500

Once you have identified the predefind value to use, set the slider's value property to that value.

app.Slder.Value = valAct;

I wrote the code the way I did so that it will execute here. You will of course need to adapt it to work within your app.

[Harpreet]

That worked, thank you for your help

[Harpreet]

Would you know if there is a way to set the step size of it using uislider instead of uicontrol, given the spacing is uniform?

[Cris LaPierre]

Sorry for the confusion. Only sliders in live tasks have a step property. So a uislider has the same properties as the slider component in an app.

If you want to only display accepted values on the tick labels, I would probably just programmatically set the slider ticks in a startupFcn. Note that a slider does not snap to the ticks. The previous answer I shared could be used for that purpose.

% Code that executes after component creation
function startupFcn(app)
    app.Slider.MajorTicks = 1.23:1.22:15;
end