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pythonuser-interfacefiremonkey

How do I make an Edit that only accepts numbers in a Python FMX GUI App?

I have a Python FMX GUI App with an Editcontrol that I want to only accept integer values with. In the past, I've done this kind of validation by overloading the KeyPress event and just removing characters that didn't fit the specification.

Is there a different way that is better? Maybe using regular expressions?

Ideally, this would behave such that pressing a non-numeric character would either produce no result or immediately provide the user with feedback about the invalid character.

Solution

  • The Edit component in FMX has a FilerChar property specifically for this purpose. So you could enter "0123456789" into the FilterChar property and then only numbers are allowed in the Edit.

    So assuming you have an Edit named "edtNumbers", you can simply write:

    self.edtNumbers.FilterChar = "0123456789"