Close kivy popup from another class - kivy

Question

I am writing a simple Vocabulary App and when the user submits an answer, a popup should display if he has answered correct or not. This works so far, but when the popup should be dismissed/closed the app crashes telling that AttributeError: 'MyScreenManager' object has no attribute 'close_pop'
which does makes sense, because the close_pop method is defined in the PopupWindow class (I'd like to separate the different concerns if possible)
I though of two possible solutions, but don't know how to realize them:
1: Call the close_pop method from within the MyScreenManager class, but I don't know how to reference the popup object that should be closed
2: Adjust the kv part:
<PopupWindow>:
pLabel: pLabel
Label:
id: pLabel
size_hint: .6, .2
pos_hint:{'x': .2, 'top': 1}
font_name: 'static/NotoSansSC-Regular.otf'
Button:
text: 'Close'
size_hint: .8, .2
pos_hint:{'x': .1, 'y': .1}
on_release: app.root.close_pop()
to not call the root class (MyScreenManager), but instead do something like app.PopupWindow.close_pop(), but this doesn't work either.
I was able to get it working without screenmanager (and putting all methods into one class 'Mainwindow' which also was the root class then) but for further enhancements I'd like to use screen manager :)
Any other fine solution will also work - thanks a lot!
Here is my Python Code:
import random
import pandas as pd
import unidecode
from kivy.app import App
#from kivy.uix.gridlayout import GridLayout
#from kivy.uix.widget import Widget
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.popup import Popup
#from kivy.uix.actionbar import ActionBar
#from kivy.uix.label import Label
from kivy.properties import ObjectProperty
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
class MainWindow(Screen):
userInput = ObjectProperty(None)
vocab = ObjectProperty(None)
def __init__(self, **kwargs):
super(MainWindow, self).__init__(**kwargs)
self.df = pd.read_excel(r"static/HSK1-Vocabulary-List.xlsx")
self.en = self.df['English']
self.zh = self.df['Chinese']
self.pinyin = self.df['Pinyin']
self.rd = None
def btn_submit(self):
if self.rd is None:
pLabel = "Please start before submitting!"
elif not self.userInput.text:
pLabel = "Please enter something!"
else:
pLabel = self.validate(self.userInput.text)
self.btn_next()
PopupWindow(pLabel).open_popup()
def btn_next(self):
self.userInput.text = ""
self.rd = random.randint(0, self.df.shape[0]-1)
self.vocab.text = "What is '{}' in Chinese?".format(self.en[self.rd])
def validate(self, answer):
def replace_tones(orig_voc):
unaccented_voc = unidecode.unidecode(orig_voc)
return(unaccented_voc)
if answer == self.zh[self.rd]:
#correct+=1
return("Well done, even in chinese characters!")
elif answer == self.pinyin[self.rd]:
#correct+=1
return("Well done, you also got the correct tones!")
elif answer == replace_tones(self.pinyin[self.rd]):
#correct+=1
return("Well done! Keep in mind the tones '{}'".format(self.pinyin[self.rd]))
else:
return("Sorry, that was not correct!\nThe correct vocab is {}".format(self.pinyin[self.rd]))
#cnt+=1
class PopupWindow(FloatLayout):
def __init__(self, userInput):
super().__init__()
self.pLabel.text = userInput
def open_popup(self):
content = PopupWindow(self.pLabel.text)
self.pop = Popup(title="Result", content=content, size_hint=(None, None), size=(400, 400))
self.pop.open()
def close_pop(self):
self.pop.dismiss()
class DashboardWindow(Screen):
pass
class MyScreenManager(ScreenManager):
pass
#def close_pop(self):
# print("This should close the popup...")
KV = Builder.load_file("main.kv")
class VocabularyTrainer(App):
def build(self):
return KV
if __name__ == "__main__":
app = VocabularyTrainer()
app.run()
and here my .kv file:
MyScreenManager:
MainWindow:
DashboardWindow:
<MainWindow>:
name: 'main'
vocab: vocab
userInput: userInput
GridLayout:
size: root.width, root.height
rows: 4
ActionBar:
id: actBar
background_image: ''
background_color: (0.53, 0.808, 0.98, 1)
ActionView:
ActionPrevious:
ActionButton:
text: 'Quiz'
ActionButton:
text: 'Training'
ActionButton:
text: 'Settings'
Label:
id: vocab
text: 'Welcome to the Chinese Learning App!'
TextInput:
id: userInput
hint_text: 'Enter answer'
width: 300
multiline: False
on_text_validate: root.btn_submit()
font_name: 'static/NotoSansSC-Regular.otf'
GridLayout:
cols: 3
Button:
text: 'Submit'
on_press: root.btn_submit()
Button:
text: 'Start/Skip'
on_press: root.btn_next()
Button:
text: 'Dashboard'
on_press: app.root.current = 'dashboard'
<PopupWindow>:
pLabel: pLabel
Label:
id: pLabel
size_hint: .6, .2
pos_hint:{'x': .2, 'top': 1}
font_name: 'static/NotoSansSC-Regular.otf'
Button:
text: 'Close'
size_hint: .8, .2
pos_hint:{'x': .1, 'y': .1}
on_release: app.root.close_pop()
<DashboardWindow>:
name: 'dashboard'
GridLayout:
rows: 2
Label:
text: '<e.g. PieChart Results>'
Button:
text: 'Go back'
on_press: app.root.current = 'main'

Answer 1

The problem is that your PopupWindow is creating two PopupWindows each time you use it. A better approach would be to just create one, like this:
class PopupWindow(FloatLayout):
def __init__(self, userInput):
super().__init__()
self.pLabel.text = userInput
self.pop = Popup(title="Result", content=self, size_hint=(None, None), size=(400, 400))
def open_popup(self):
self.pop.open()
def close_pop(self):
self.pop.dismiss()
Then in your kv you can use:
<PopupWindow>:
pLabel: pLabel
Label:
id: pLabel
size_hint: .6, .2
pos_hint:{'x': .2, 'top': 1}
font_name: 'static/NotoSansSC-Regular.otf'
Button:
text: 'Close'
size_hint: .8, .2
pos_hint:{'x': .1, 'y': .1}
on_release: root.close_pop()

Answer 2

You should break it down to a simple example of your problem. From what I have seen so far you should try to change your btn_submit method to something like this to make the popup accessible easily:
def btn_submit(self):
if self.rd is None:
pLabel = "Please start before submitting!"
elif not self.userInput.text:
pLabel = "Please enter something!"
else:
pLabel = self.validate(self.userInput.text)
self.btn_next()
self.mypopup = PopupWindow(pLabel)
self.mypopup.open_popup()
and then you should be able to access it with your screenmanager like this:
class MyScreenManager(ScreenManager):
def close_pop(self):
print("This should close the popup...")
self.get_screen('main').mypopup.close_pop()