Kivy GUI (Python) falling into a segmentation fault when trying to update the screen

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I have this simple program for displaying text on a screen using python and kivy but I cannot get my screen to update. I have tried using what is written below but it keeps crashing with the error 'segmentation fault'. I believe the issue my be caused by the def _init_ because if I remove it the fault goes away but the screen still does not update.

class ScreenDivider(Widget):
    def __init__(self):
        self.score = 12
        #Clock.schedule_interval(self.UpdateText,1) I tried using this way but no luck

    def UpdateText(self, dt):
        self.score += 1


class Screen(App):

    ####################### Ignore from here ##################
    stocksSearchArray = GrabStockList() # Grab the list of stocks I want to see 
    
    global stocksOnScreen # List of the stocks currently displayed on LED screen
    global stocksOnScreenListInfo # The quote information for the stocks on screen 
    stocksOnScreen = []
    stocksOnScreenListInfo = []
    
    # Thread to handle constant data collection 
    thread_data_collector = threading.Thread(target=dataCollector_thread)
    thread_data_collector.daemon = True
    thread_data_collector.start()

    # Thread to handle screen update
    thread_whatsonscreen = threading.Thread(target=screenUpdate_thread, args=(stocksSearchArray,))
    thread_whatsonscreen.daemon = True
    thread_whatsonscreen.start()

    # Handle user input 
    thread_inputHandle = threading.Thread(target=userInput_thread, args=(stocksSearchArray,))
    thread_inputHandle.daemon = True
    thread_inputHandle.start()

    ####################### Ignore to here ##################


    # Build the screen 
    def build(self):
        screen = ScreenDivider()
        Clock.schedule_interval(screen.UpdateText, 1.0 / 60.0)
        return screen

if __name__ == "__main__":
    Screen().run()

The .ky file

#:kivy 1.0.9

<ScreenDivider>:    
    name: 'program'
    canvas:
        Line:
            points: 0,root.height*0.2,root.width,root.height*0.2
            
    Label:
        font_size: 70  
        center_x: root.width / 4
        top: root.top - 50
        text: str(root.score)
kivy class python
1 Answers

When you extend a class and define an __init__() method for that class, you normally must call the super class __init__() method. Just add that to your ScreenDivider class:

class ScreenDivider(Widget):
    def __init__(self):
        super(ScreenDivider, self).__init__()  # call super __init__()
        self.score = 12
        # Clock.schedule_interval(self.UpdateText,1) I tried using this way but no luck

Since you are referencing score in your kv, you will want that to be a property of ScreenDivider (otherwise the Label will not update when you change score). So adding that property in the class definition:

class ScreenDivider(Widget):
    score = NumericProperty(0)
    def __init__(self):
        super(ScreenDivider, self).__init__()  # call super __init__()
        self.score = 12
user_72546330
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