[Kivy] Need to render updated recycler view

[test]

I changed the widget hierarchy a little bit hoping that will make it scroll...still no good..
here's the code:

import kivy
kivy.require('1.0.8')

import openpyxl
from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.scrollview import ScrollView
from kivy.uix.gridlayout import GridLayout
from kivy.uix.boxlayout import BoxLayout

class AllApp(App):

	layout = BoxLayout(orientation='horizontal')
	layout_questions = BoxLayout(orientation='vertical')

	def get_questions(self, subject):
		print(subject)
		wb = openpyxl.load_workbook('sWL.xlsx')
		sheet = wb[subject]
		data = []
		for row in range (2, sheet.max_row+1):
			question = sheet.cell(row=row, column=1).value
			data.append(question)
		return self.add_questions(data)

	def add_questions(self, data):
		self.layout_questions.clear_widgets()
		for question in data:
			question = Button(text= question, size=(480, 40), size_hint=(None, None))
			self.layout_questions.add_widget(question)

	def build(self):
		layout_subjects = BoxLayout(orientation='vertical')
		subjects = ['Anatomy', 'Biochemistry', 'Physiology', 'Pharmacology', 'Pathology', 'Microbiology', 'FMT', 'Ophthalmology', 'ENT', 'PSM', 'OG', 'Surgery', 'Internal_Medicine', 'Paediatrics', 'Anaesthesia', 'Radiology', 'Dermatology', 'Orthopaedics', 'Psychiatry']		
		subjects_d = {}
		for subject in subjects:
			subjects_d[subject] = subject
		print(subjects_d)
		for k, v in subjects_d.items():
			k = Button(text = v, size=(480, 40), size_hint=(None, None))
			k.bind(on_press= lambda k: self.get_questions(k.text))
			layout_subjects.add_widget(k)
		
			
		root = BoxLayout()
		scroll_subject = ScrollView()
		scroll_question = ScrollView()
		root.add_widget(self.layout)
		self.layout.add_widget(scroll_subject)
		scroll_subject.add_widget(layout_subjects)
		self.layout.add_widget(scroll_question)
		scroll_question.add_widget(self.layout_questions)


		return root



if __name__ == '__main__':
	AllApp().run()

---

Fixed the scrolling problem...

import kivy
kivy.require('1.0.8')

import openpyxl
from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.scrollview import ScrollView
from kivy.uix.gridlayout import GridLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.app import runTouchApp

class AllApp(App):

	layout = BoxLayout(orientation='horizontal')
	layout_questions = GridLayout(cols=1, size_hint=(None, None), width=400, height=5500)

	def get_questions(self, subject):
		print(subject)
		wb = openpyxl.load_workbook('sWL.xlsx')
		sheet = wb[subject]
		data = []
		for row in range (2, sheet.max_row+1):
			question = sheet.cell(row=row, column=1).value
			data.append(question)
		return self.add_questions(data)

	def add_questions(self, data):
		self.layout_questions.clear_widgets()
		for question in data:
			question = Button(text= question, size=(480, 40), size_hint=(1, None))
			self.layout_questions.add_widget(question)

	def build(self):
		layout_subjects = GridLayout(cols=1, size_hint=(None, None), width=400, height=1000)
		subjects = ['Anatomy', 'Biochemistry', 'Physiology', 'Pharmacology', 'Pathology', 'Microbiology', 'FMT', 'Ophthalmology', 'ENT', 'PSM', 'OG', 'Surgery', 'Internal_Medicine', 'Paediatrics', 'Anaesthesia', 'Radiology', 'Dermatology', 'Orthopaedics', 'Psychiatry']		
		subjects_d = {}
		for subject in subjects:
			subjects_d[subject] = subject
		print(subjects_d)
		for k, v in subjects_d.items():
			k = Button(text = v, size=(480, 40), size_hint=(1, None))
			k.bind(on_press= lambda k: self.get_questions(k.text))
			layout_subjects.add_widget(k)
		
			
		root = BoxLayout()
		scroll_subject = ScrollView(size_hint=(1, 1))
		scroll_question = ScrollView(size_hint=(1, 1))
		root.add_widget(self.layout)
		self.layout.add_widget(scroll_subject)
		scroll_subject.add_widget(layout_subjects)
		self.layout.add_widget(scroll_question)
		scroll_question.add_widget(self.layout_questions)
		
		# runTouchApp(scroll_subject)
		# runTouchApp(scroll_question)

		return root



if __name__ == '__main__':
	AllApp().run()

Apologies if I am being annoying.