How can I remove information from the screen and reuse the method of displaying information on this-CodePudding

Please help me figure it out. I’m beginner in learning Python.

The training program I'm currently working on, counts items sold.

The CoffeeWindow and TeaWindow screens have buttons with items (coffee, tea) that the program counts when pressed.

On the TotalWindow screen, the program should show the amount of selected items and their general price as one order. After pressing the Delete button, the program should delete the contents of this screen in order to show the next new order.

I can't figure out, how I can clear the result of the set_label_text method and run it again after pressing the Delete button. I created a delete_total method that runs after clicking on Delete, in it I change the text label to ‘ ’ and change the price list to empty list, it seems to work, the text is removed from the screen. But when you press any buttons with items, the result is shown the same plus new.

I try different ways but nothing works. What am I doing wrong?

Thanks in advance!

main.py:

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen


class TotalWindow(Screen):

    def on_pre_enter(self, *args):

        coffee = self.manager.ids.coffee.clickCounter
        tea = self.manager.ids.tea.clickCounter

        big_dict = {**coffee, **tea}

        self.price_list = []
        for item_name, count in big_dict.items():
            self.price_list.append(count[0] * count[1])


        self.set_label_text(big_dict, self.ids.label1)


    def delete_total(self):

        self.ids.label1.text = ""
        self.price_list = []


    def set_label_text(self, counts, label):

        label.text = ""
        for item_name, count in counts.items():
            label.text  = f"{item_name} ({count[0]})\n"

        label.text  = "\nTotal Price: "   str(sum(self.price_list))



class CoffeeWindow(Screen):

    clickCounter = {}

    def count(self, name, price):

        self.clickCounter.setdefault(name, [0, price])
        self.clickCounter[name][0]  = 1


class TeaWindow(Screen):

    clickCounter = {}

    def count(self, name, price):

        self.clickCounter.setdefault(name, [0, price])
        self.clickCounter[name][0]  = 1


class MainWindow(Screen):
    pass


class WindowManager(ScreenManager):
    pass


kv = Builder.load_file('my.kv')


class MainApp(App):

    def build(self):
        return kv


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

my.kv:

<ItemButton@Button>:
    size_hint: 0.5, 0.12
    bold: True


WindowManager:
    MainWindow:
        id: main
    CoffeeWindow:
        id: coffee
    TeaWindow:
        id: tea
    TotalWindow:
        id: total


<TotalWindow>:
    name: "total"

    BoxLayout:
        orientation: "vertical"
        pos_hint: {'x' : 0, 'center_y' : 0.57}
        size_hint: 1, 0.88

        Label:
            id: label1

    Button:
        size_hint: 0.5, 0.1
        pos_hint: {'right' : 0.5, 'y' : 0}
        text: "Go to Main"
        on_release:
            app.root.current = "main_window"
            app.root.transition.direction = "right"

    Button:
        size_hint: 0.5, 0.1
        pos_hint: {'right' : 1, 'y' : 0}
        text: "Delete"
        on_release:
            root.delete_total()


<MainWindow>:
    name: "main_window"

    BoxLayout:

        ItemButton:
            text: "Go to Coffee"
            pos_hint: {'x' : 0, 'center_y' : 0.5}
            on_release:
                app.root.current = "coffee"
                app.root.transition.direction = "left"

        ItemButton:
            text: "Go to Tea"
            pos_hint: {'x' : 0, 'center_y' : 0.5}
            on_release:
                app.root.current = "tea"
                app.root.transition.direction = "left"


<CoffeeWindow>:
    name: "coffee"

    GridLayout:
        rows: 3
        size_hint: 1, 0.8
        pos_hint: {'center_x' : 0.5, 'top' : 0.95}

        ItemButton:
            text: "black coffee"
            on_release:
                root.count("black coffee", 20)

        ItemButton:
            text: "milk coffee"
            on_release:
                root.count("milk coffee", 20)


        Button:
            size_hint: 0.5, 0.1
            text: "Show Total Menu"
            on_release:
                app.root.current = "total"
                app.root.transition.direction = "left"

        Button:
            size_hint: 0.5, 0.1
            text: "Go to Main"
            on_release:
                app.root.current = "main_window"
                app.root.transition.direction = "right"


<TeaWindow>:
    name: "tea"

    GridLayout:
        rows: 3
        size_hint: 1, 0.8
        pos_hint: {'center_x' : 0.5, 'top' : 0.95}

        ItemButton:
            text: "green tea"
            on_release:
                root.count("green tea", 20)

        ItemButton:
            text: "black tea"
            on_release:
                root.count("black tea", 20)

        Button:
            size_hint: 0.5, 0.1
            text: "Show Total Menu"
            on_release:
                app.root.current = "total"
                app.root.transition.direction = "left"

        Button:
            size_hint: 0.5, 0.1
            text: "Go to Main"
            on_release:
                app.root.current = "main_window"
                app.root.transition.direction = "right"

CodePudding user response：

Your delete_total() method is clearing the text, but not removing the counts in your clickCounters. You can clear the counts by adding lines to your delete_total() method:

def delete_total(self):

    self.ids.label1.text = ""
    self.price_list = []
    self.manager.ids.coffee.clickCounter = {}
    self.manager.ids.tea.clickCounter = {}