Segmentation fault in real numeric pad on iPad

[cvp]

For @estephan500 and @runjaj I begin to (try to) create a real numeric pad on iPad.
The code is not yet finished nor nice but when I test it, I get a segmentation fault when I type the backspace key for the 2nd time...
Help of a guru is needed 😢

import ui
from objc_util import *

# To store TextField associated with key-button, we need to use a python class
# for the button, not an ui.Button it-self
# idea found here https://forum.omz-software.com/topic/1913/attaching-a-class-to-a-ui-element-such-as-uibutton-i-am-desperate
class CustomAction(object):
		def __init__(self, TextField):
			self.action = self.real_action
			self.TextField = TextField

		def __call__(self, sender):
			return self.action(sender)

		def real_action(self, sender):

			tfb = self.TextField
			if sender.name == 'x':
				if tfb.text != '':
					tfb.text = tfb.text[:-1]
			elif sender.name == 'y':
				tfb.end_editing()
			else:
				tfb.text = tfb.text + sender.title

def SetTextFieldAsNumeric(tf):
	tfo = ObjCInstance(tf).textField() # UITextField is subview of ui.TextField
	#print(dir(tfo))
	
	keys = '123x|456|789y| 0'
	#keys = '1234567890x y'
	rows = keys.split('|')
	row_length = 0
	for row in rows:
		if len(row) > row_length:
			row_length = len(row)

	v = ui.View()
	db = 50
	dd = 10
	x0 = (ui.get_screen_size()[0]-row_length*db-(row_length-1)*dd)/2
	x = x0
	y = 0

	for row in rows:
		for c in row:
			if c != ' ':
				b = ui.Button()
				b.name = c
				b.background_color = 'white'
				b.tint_color = 'black'
				b.corner_radius = 10 
				if c == 'x':
					b.image = ui.Image.named('typb:Delete')
				elif c == 'y':
					b.title = ''
					b.image = ui.Image.named('iob:ios7_checkmark_outline_32')
				else:
					b.title = c
				b.font = ('<system>',32)
				b.frame = (x,y,db,db)
				b.action = CustomAction(tf)	# to store TextField in button
				v.add_subview(b)
			x = x + db + dd
		y = y + db + dd
		x = x0

	v.width = ui.get_screen_size()[0]
	v.height = y

	# view of keyboard
	tfo.setInputView_(ObjCInstance(v))
 
tf = ui.TextField()

SetTextFieldAsNumeric(tf)
tf.text = ''
tf.present('sheet')
tf.begin_editing()
tf.wait_modal()

[cvp]

reading here solves the problem, add:

	retain_global(v)

Before

	tfo.setInputView_(ObjCInstance(v))

[JonB]

really great idea!

by the way, in recent pythonista versions, you can add attributes to buttons directly. therefore, you can say
b.Textfield =Textfield,
and your button action can therefore access sender.Textfield.
That CustomAction was for previous versions where you could not add custom attributes to buttons.

[cvp]

@JonB Thanks a lot, will make code easier