How to access appdesigner uicontrol input validation such as seen on NumericEditField?

The ui control NumericEditField has 'built-in' validation when the limits are enabled, preventing the user from entering a number outwith these limits and displaying a popup tote if attempted. Is it possible to manipulate this validation that MATLAB carries out? Ideally I would like to be able to implement this on both numeric and text field boxes, for example to enable a EditField control to only accept hex input, and in the event of a non hex character being enabled the dialog tote would appear informing the user to only enter hex characters. This should not trigger the value changed callback á la the NumericEditField case.

[Greg]

I doubt it.

It's easy enough to do the validation at the top of the ValueChangedFcn, using event.PreviousData or event.PreviousValue then return to "abort" the change.

[A Mackie]

Greg, thank you for your input. Its useful to be able to 'abort' the change as you put it, but ideally I was hoping to be able to manipulate the popup tote I describe, such as to give the user feedback as to why their input has been reverted. If this isn't possible then I think your solution, coupled with a label informing the user of their 'mistake' is probably the best/easiest solution; although I was rather hoping to minimise the clutter in the ui.

[Greg]

The new functions uialert and uiconfirm are a nice-ish way to mimic the "popup tote."