Python，Kivy。通过下拉列表从动态创建的按钮获取文本

Question

我正在动态创建按钮并为每个按钮动态创建下拉列表。选择按钮时，主按钮上的文本值会更新。 我想将主要按钮更新的文本值导入Run_DrawsTest（）。 我一直在尝试运行按钮ID来获取文本值。通常是btn_txt = self.ids.button_id_name.text。 由于按钮是动态创建的，我无法预见将创建的数量，我不知道如何获得文本

        for i in range(row_count):
            drpName.append(DropDown())
            btnName = Button(text="Select", size_hint_y= self.size_hint_y)
            self.cnt_btns += 1
            for e in self.sel:
                self.ssbtn = ('tbtn' +  str(sbtn))
                sbtn += 1

                btn = Button(text=e, size_hint_y=None, height=25, id=self.ssbtn)
                btn.bind(on_release=lambda btn=btn, dropdown=drpName[i]: dropdown.select(btn.text))
                drpName[i].add_widget(btn)
            btnName.bind(on_release=drpName[i].open)
            drpName[i].bind(on_select=lambda instance, x, btn=btnName: setattr(btn, 'text', x))

            self.ids.select_btn.add_widget(btnName)
            self.my_btn_names.append(self.ssbtn)

def Run_Draws_Test (self):
    counter = 0
    vals = [ ]
    while counter != self.cnt_btns:
        btn_ids = (self.my_btn_names[counter])
        txt = ('txt' + str(counter))

        s = btn_ids
        btn_texts = str(txt + ' = ' + "self.ids." + s + ".text")
        vals.append(btn_texts)

        executable_code = (vals[counter])
        print(executable_code)
        time.sleep(3)
        exec(str(executable_code))
        print(txt)
        counter += 1

Answer 1

使用 on_select 事件将所选文本传递给方法。有关详细信息，请参阅代码段和示例。

Snippets - kv file

<CustomDropDown>:
    on_select:
        app.root.ids.Notes.ids.mainbutton.text = '{}'.format(args[1])
        app.root.Run_Draws_Test(args[1])

实施例

main.py

from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.dropdown import DropDown
from kivy.uix.button import Button
from kivy.core.window import Window


Window.size = (800, 480)


class CustomDropDown(DropDown):

    def __init__(self, **kwargs):
        super(CustomDropDown, self).__init__(**kwargs)
        self.add_buttons()

    def add_buttons(self):
        for index in range(10):
            # When adding widgets, we need to specify the height manually
            # (disabling the size_hint_y) so the dropdown can calculate
            # the area it needs.

            btn = Button(text='Value %d' % index, size_hint_y=None, height=44)

            # for each button, attach a callback that will call the select() method
            # on the dropdown. We'll pass the text of the button as the data of the
            # selection.
            btn.bind(on_release=lambda btn: self.select(btn.text))

            # then add the button inside the dropdown
            self.add_widget(btn)


class Notes(Screen):
    pass


class MyScreenManager(ScreenManager):

    def Run_Draws_Test(self, value):
        print(value)


class TestApp(App):
    title = "Kivy Drop-Down List Demo"

    def build(self):
        return MyScreenManager()


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

test.kv

#:kivy 1.10.0
#:import Factory kivy.factory.Factory

<CustomDropDown>:
    on_select:
        app.root.ids.Notes.ids.mainbutton.text = '{}'.format(args[1])
        app.root.Run_Draws_Test(args[1])


<Notes>:
    orientation: "vertical"

    FloatLayout:
        size_hint: None, None

        canvas.before:
            Color:
                rgba: 1, 1, 0, 1

        Button:
            id: mainbutton
            text: "Menu name"
            font_size: 20
            size_hint: None, None
            size: 150, 50
            pos: 20,400
            on_release: Factory.CustomDropDown().open(self)

<MyScreenManager>:
    canvas.before:
        Color:
            rgba: 0.5, 0.5, 0.5, 0.5
        Rectangle:
            pos: 0,0
            size: 800, 480
    Notes:
        id:Notes
        name: 'Notes'

输出