如何为 kivyMD 按钮分配一个功能

Question

我是 kivy 和 kivymd 的新手，我有一个问题。问题是我需要为 KivyMD RectangleFlatButton 分配一个函数来打开一个网站，但我不知道该怎么做。请告诉我怎么做。

这是我试过的；

from kivy.lang import Builder
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import ObjectProperty

from kivymd.app import MDApp

import webbrowser

class func():
    def open():
        webbrowser.open('google.com')

KV = '''
<ContentNavigationDrawer>:
    orientation: "vertical"
    padding: "8dp"

    ScrollView:

        MDList:

            MDLabel:
                text: "App"
                font_style: "H3"
                size_hint_y: None
                height: self.texture_size[1]

            OneLineListItem:
                text: "1"
                on_press:
                    root.nav_drawer.set_state("close")
                    root.screen_manager.current = "scr 1"

            OneLineListItem:
                text: "2"
                on_press:
                    root.nav_drawer.set_state("close")
                    root.screen_manager.current = "scr 2"

            OneLineListItem:
                text: "3"
                on_press:
                    root.nav_drawer.set_state("close")
                    root.screen_manager.current = "scr 2"


Screen:
    pos: 0, root.height - 591

    MDToolbar:
        id: toolbar
        pos_hint: {"top": 1}
        elevation: 10
        title: "App"
        left_action_items: [["menu", lambda x: nav_drawer.set_state("open")]]

    NavigationLayout:
        x: toolbar.height

        ScreenManager:
            id: screen_manager

            Screen:
                name: "scr 1"

                BoxLayout:
                    orientation: "vertical"
                    padding: "10db"
                
                    MDLabel:
                        text: "Google"
                        font_style: "H3"
                        halign: "center"

                    MDLabel:
                        text: "Go to google!!!"
                        font_style: "Body2"
                        halign: "center"

                    MDRectangleFlatButton:
                        id: "button1"
                        text: "Go to Google"
                        pos_hint: {"center_x": 0.5}
                        on_press: func.open()

            Screen:
                name: "scr 2"

                MDLabel:
                    text: "Screen 2"
                    halign: "center"

        MDNavigationDrawer:
            id: nav_drawer

            ContentNavigationDrawer:
                screen_manager: screen_manager
                nav_drawer: nav_drawer
'''


class ContentNavigationDrawer(BoxLayout):
    screen_manager = ObjectProperty()
    nav_drawer = ObjectProperty()



class App(MDApp):
    def build(self):
        return Builder.load_string(KV)


App().run()

但是当我运行代码出现错误时。这是错误；

Traceback (most recent call last):
   File "c:/Users/DTLM/Desktop/Python/kivy/app.py", line 113, in <module>
     EduLink().run()
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\app.py", line 950, in run
     runTouchApp()
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\base.py", line 573, in runTouchApp
     EventLoop.mainloop()
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\base.py", line 347, in mainloop
     self.idle()
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\base.py", line 391, in idle
     self.dispatch_input()
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\base.py", line 342, in dispatch_input
     post_dispatch_input(*pop(0))
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\base.py", line 248, in post_dispatch_input
     listener.dispatch('on_motion', etype, me)
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\core\window\__init__.py", line 1412, in on_motion
     self.dispatch('on_touch_down', me)
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\core\window\__init__.py", line 1428, in on_touch_down
     if w.dispatch('on_touch_down', touch):
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\relativelayout.py", line 297, in on_touch_down
     ret = super(RelativeLayout, self).on_touch_down(touch)
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\widget.py", line 545, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\widget.py", line 545, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\screenmanager.py", line 1198, in on_touch_down
     return super(ScreenManager, self).on_touch_down(touch)
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\widget.py", line 545, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\relativelayout.py", line 297, in on_touch_down
     ret = super(RelativeLayout, self).on_touch_down(touch)
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\widget.py", line 545, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\widget.py", line 545, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy\_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivymd\uix\behaviors\ripplebehavior.py", line 231, in on_touch_down
     return super().on_touch_down(touch)
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivymd\uix\button.py", line 961, in on_touch_down
     return super().on_touch_down(touch)
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\uix\behaviors\button.py", line 151, in on_touch_down
     self.dispatch('on_press')
   File "kivy\_event.pyx", line 705, in kivy._event.EventDispatcher.dispatch
   File "kivy\_event.pyx", line 1248, in kivy._event.EventObservers.dispatch
   File "kivy\_event.pyx", line 1132, in kivy._event.EventObservers._dispatch
   File "C:\Users\DTLM\AppData\Local\Programs\Python\Python38\lib\site-packages\kivy\lang\builder.py", line 57, in custom_callback
     exec(__kvlang__.co_value, idmap)
   File "<string>", line 72, in <module>
 NameError: name 'func' is not defined

请帮忙，谢谢。

Answer 1

在您的 kv 文件中，在开头插入：

#:import webbrowser webbrowser

那么你的on_press可以是：

on_press: webbrowser.open('http://google.com')

如何为 kivyMD 按钮分配一个功能

How to assign a function to a kivyMD button

python-webbrowser

kivy

python-3.6

kivy-language

kivymd