如何在kivy modalview中動態更新標記文本

Question

我正在嘗試從ModalView中TextInput的內容動態更新標簽字段。 這個想法是，在TextInput中輸入純文本，包括標記格式，您將在帶有markup = True的Label字段中直接看到結果。

不幸的是，我不知道如何訪問ModalView中的Label項。 誰能幫忙？ 請參見下面的示例代碼。

提前致謝。

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.modalview import ModalView
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.textinput import TextInput
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.properties import ObjectProperty, StringProperty

kv = """
<Test>:
    canvas:
        Color:
            rgba: 0.4, 0.5, 0.6, 1
        Rectangle:
            size: self.size
            pos: self.pos
    Button:
        size_hint: None, None
        size: 3 * dp(48), dp(48)
        text: 'Edit'
        on_press: root.showedit()
"""

Builder.load_string(kv)


class Test(BoxLayout):
    minput_text = StringProperty('Welcome')
    txtresult = ObjectProperty()

    def showedit(self):
        mview = ModalView(id='mviewid', size_hint=(0.4, 0.6), auto_dismiss=False, background='./images/noimage.png')
        mblt = BoxLayout(orientation='vertical', padding=(24))
        minp = TextInput(id='inptxt', text='', hint_text='Start typing text with markup here', size_hint=(1,0.5),multiline=True)
        minp.bind(text=self.on_inptext)

        mtxt = Label(id='txtresult',text='displays formatted text', color=(0.3,0.3,0.3), size_hint=(1,0.5),markup=True)
        mcnf = Button(text='OK', size=(144,48), size_hint=(None,None))
        mcnf.bind(on_press=mview.dismiss)

        mblt.add_widget(minp)
        mblt.add_widget(mtxt)
        mblt.add_widget(mcnf)
        mview.add_widget(mblt)
        mview.bind(on_dismiss=self.print_text)
        mview.open()

    def on_inptext(self, instance, value):
        self.minput_text = value

    def print_text(self, *args):
        print self.minput_text


class TestApp(App):
    def build(self):
        return Test()


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

Answer 1

您必須在TextIntput文本和Label之間進行綁定，為此，我們可以使用lambda函數和setattr 。

class Test(BoxLayout):
    minput_text = StringProperty('Welcome')
    txtresult = ObjectProperty()

    def showedit(self):
        mview = ModalView(id='mviewid', size_hint=(0.4, 0.6), auto_dismiss=False, background='./images/noimage.png')
        mblt = BoxLayout(orientation='vertical', padding=(24))
        minp = TextInput(id='inptxt', text='', hint_text='Start typing text with markup here', size_hint=(1,0.5),multiline=True)
        minp.bind(text=self.on_inptext)

        mtxt = Label(id='txtresult',text='displays formatted text', color=(0.3,0.3,0.3), size_hint=(1,0.5),markup=True)
        mcnf = Button(text='OK', size=(144,48), size_hint=(None,None))
        mcnf.bind(on_press=mview.dismiss)

        mblt.add_widget(minp)
        mblt.add_widget(mtxt)
        mblt.add_widget(mcnf)
        mview.add_widget(mblt)
        mview.bind(on_dismiss=self.print_text)
        # binding between TextInput text and Label text
        minp.bind(text=lambda instance, value: setattr(mtxt, 'text',value))

        mview.open()

    def on_inptext(self, instance, value):
        self.minput_text = value

    def print_text(self, *args):
        print(self.minput_text)