Source code for DroneProject.FloatInput

import re
from kivy.uix.textinput import TextInput


#Name:        James Hall
#Student No.: C00007006
#Institute:   Institute of Technology Carlow
#Project:     Drone Traffic Control System     
#Date:        April 2021 
#License:     GNU Affero General Public License v3.0

#FloatInput class

class FloatInput(TextInput):
    """
    Class designed to ensure only floats can be used for text input for lat/long values.

    Source: https://kivy.org/doc/stable/api_kivy.uix.textinput.html
    """    
    pat = re.compile('[^-|0-9]')
    def insert_text(self, substring, from_undo=False):
        pat = self.pat
        if '.' in self.text:
            s = re.sub(pat, '', substring)
        else:
            s = '.'.join([re.sub(pat, '', s) for s  in substring.split('.', 1)])
        return super(FloatInput, self).insert_text(s, from_undo=from_undo)