我想将文本字段 in.kv 文件中的文本加载到变量 in.py 文件中

Question

I want to be able to click on MDFlatButton that says Štart and i want it to let's say for an example to call get_user_input(self) which would print whatever is inside text field. And I have been struggling with this for 2 whole days and i have no idea what to do, I am just a beginner and I have no clue what am I doing so sorry if it's messy. Ty for help, those are my files: main.py file:

from kivy.core.window import Window
from kivy.lang import Builder
from kivy.properties import ObjectProperty
from kivymd.app import MDApp
from kivy.uix.screenmanager import Screen, ScreenManager
from kivymd.uix.menu import MDDropdownMenu
from kivymd.uix.textfield import MDTextField
from kivy.properties import StringProperty

class testy(Screen):
    novy_test = ObjectProperty()


class Test(MDApp):

    Window.size = (1170 / 3, 2532 / 3)
    # input_number = ObjectProperty()
    def build(self):
        self.theme_cls.material_style = "M3"
        self.theme_cls.theme_style = "Dark"
        self.theme_cls.primary_palette = 'Gray'


        return testy()
    def get_user_input(self):
        print(self.root.ids.my_textfield_1.ids.user.text)
    def callback(self, button):
        pass



class CustomOverFlowMenu(MDDropdownMenu):
    # In this class you can set custom properties for the overflow menu.
    pass

Test().run()

test.kv file:

#:import Factory kivy.factory.Factory

#:import CustomOverFlowMenu __main__.CustomOverFlowMenu

<testy>:
    name:'testy'
    id: testy
    MDBoxLayout:
        orientation: "vertical"

        MDTopAppBar:
            title: "MDTopAppBar"
            use_overflow: True
            overflow_cls: CustomOverFlowMenu()
            specific_text_color: .51,.51,.51,1
            md_bg_color: 0, 0, 0, 1



            left_action_items: [["car", lambda x: Factory.novy_test().open(), '',"Nový test"]]


        MDBottomNavigation:
            panel_color: "black"
            selected_color_background: "white"
            text_color_active: "lightgray"
            selected_color_background: 1, 1, 1, .4

            MDBottomNavigationItem:
                name: 'screen 1'
                text: 'Testy'
                icon: 'road-variant'

                MDLabel:
                    text: 'Test'
                    halign: 'center'


            MDBottomNavigationItem:
                name: 'screen 2'
                text: 'chyby'
                icon: 'alert-circle'


                MDLabel:
                    text: 'Chyby'
                    halign: 'center'

            MDBottomNavigationItem:
                name: 'screen 3'
                text: 'Settings'
                icon: 'cog'

                MDLabel:
                    text: 'LinkedIN'
                    halign: 'center'
<novy_test@Popup>:
    id:my_textfield_1
    size_hint: .8, .45
    title: 'Nový test'
    separator_color: 'black'

    title_align: 'center'
    BoxLayout:
        id: layout

        spacing: 10
        orientation:'vertical'

        MDTextField:
            id: user
            hint_text: "Číslo testu"
            mode: "round"
            pos_hint: {"top": 1}

        MDFlatButton:
            text: 'Štart'
            pos_hint: {'center_x': .5}
            on_press: app.get_user_input()


        MDFlatButton:
            pos_hint: {'center_x': .5}
            text:'test z nesprávnych'
        MDFlatButton:
            text:'test z neurobených'
            pos_hint: {'center_x': .5}
        MDFlatButton:
            text:'test z neurobených'
            pos_hint: {'center_x': .5}
        MDFlatButton:
            text:'test z neurobených'
            pos_hint: {'center_x': .5}

Answer 1

I didn't perfectly understand all that you wanted to do, but in this example, the text a person types into the box will print. I moved the.kv language into a string just for convenience of creating a one-file runnable project. I tested it.

The main point is this code, inside the.kv file/kivy language you can use the id property to get a reference to the objects, and then the.text property of that object is sent as an argument to the function.

on_press: app.get_user_input(user.text)

runnable:

from kivy.core.window import Window
from kivy.lang import Builder
from kivymd.app import MDApp
from kivy.uix.screenmanager import Screen, ScreenManager
from kivymd.uix.menu import MDDropdownMenu
from kivy.uix.popup import Popup
from kivymd.uix.textfield import MDTextField
from kivy.properties import StringProperty

Builder.load_string('''
#:import Factory kivy.factory.Factory

<testy>:
    name:'testy'
    id: testy
    MDBoxLayout:
        orientation: "vertical"
        MDTopAppBar:
            title: "MDTopAppBar"
            use_overflow: True
            # overflow_cls: CustomOverFlowMenu()
            specific_text_color: .51,.51,.51,1
            md_bg_color: 0, 0, 0, 1
            left_action_items: [["car", lambda x: Factory.NovyTest().open(), '',"Nový test"]]
        MDBottomNavigation:
            panel_color: "black"
            selected_color_background: "white"
            text_color_active: "lightgray"
            selected_color_background: 1, 1, 1, .4
            MDBottomNavigationItem:
                name: 'screen 1'
                text: 'Testy'
                icon: 'road-variant'
                MDLabel:
                    text: 'Test'
                    halign: 'center'
            MDBottomNavigationItem:
                name: 'screen 2'
                text: 'chyby'
                icon: 'alert-circle'
                MDLabel:
                    text: 'Chyby'
                    halign: 'center'
            MDBottomNavigationItem:
                name: 'screen 3'
                text: 'Settings'
                icon: 'cog'
                MDLabel:
                    text: 'LinkedIN'
                    halign: 'center'
<NovyTest@Popup>:
    id:my_textfield_1
    size_hint: .8, .45
    title: 'Nový test'
    separator_color: 'black'
    title_align: 'center'
    BoxLayout:
        id: layout
        spacing: 10
        orientation:'vertical'
        MDTextField:
            id: user
            hint_text: "Číslo testu"
            mode: "round"
            pos_hint: {"top": 1}
        MDFlatButton:
            text: 'Štart'
            pos_hint: {'center_x': .5}
            # inside .kv/kivy language you can use the id property
            on_press: app.get_user_input(user.text)
        MDFlatButton:
            pos_hint: {'center_x': .5}
            text:'test z nesprávnych'
        MDFlatButton:
            text:'test z neurobených'
            pos_hint: {'center_x': .5}
        MDFlatButton:
            text:'test z neurobených'
            pos_hint: {'center_x': .5}
        MDFlatButton:
            text:'test z neurobených'
            pos_hint: {'center_x': .5}
'''
)


class NovyTest(Popup):
    # just an example, not used in this code
    def __init__(self, **kw):
        super().__init__(**kw)


class testy(Screen):
    # can list objects defined in .kv file and give them a type hint corresponding to object type
    novy_test: NovyTest

    def __init__(self, **kw):
        super().__init__(**kw)
        print("creating screen testy")

    # novy_test = ObjectProperty()


class Test(MDApp):

    Window.size = (1170 / 3, 2532 / 3)
    # input_number = ObjectProperty()

    def build(self) -> testy:
        self.theme_cls.material_style = "M3"
        self.theme_cls.theme_style = "Dark"
        self.theme_cls.primary_palette = 'Gray'
        return testy()

    def get_user_input(self, input_text, *args):
        print(f"{self} user input: {input_text}")
        # print(self.root.ids.my_textfield_1.ids.user.text)

    def callback(self, button):
        pass


class CustomOverFlowMenu(MDDropdownMenu):
    # In this class you can set custom properties for the overflow menu.
    pass


Test().run()

end