Kivy自定義事件傳播

Question

我正在制作用於互聯網連接設備的Python / Kivy GUI。 由於該設備使用WAMP pub / sub方法進行通信，因此發生了很多同步事情。 問題是我不知道如何將自定義事件（例如on_connect，on_disconnect等）從kivy應用程序傳播到適當的kivy小部件。

這就是我現在所擁有的，為了獲得更好的可讀性，剝去了最低限度的要求，還有模擬連接事件的虛擬連接按鈕。

MyApp.py：

from kivy.app import App
from kivy.config import Config
from MainPage import MainPage
from AboutPage import AboutPage
from MainContainer import MainContainer

class MyApp(App):
    def build(self):
        self.container = MainContainer()
        self.register_event_type('on_connect')
        return self.container

    def on_session(self, session):
        print("session connected!")
        self.session = session
        self.dispatch('on_connect')

    def on_connect(self, *args):
        pass
MyApp().run()

my.kv：

#:kivy 1.10.1
#:import CardTransition kivy.uix.screenmanager.CardTransition
#:set menucolor1 0, 0.603, 0.784, 1
#:set menucolor2 0, 0.203, 0.384, 1
#:set backgroundcolor 0.95, 0.95, 0.95, 1

<MenuButton@Button>:
    size_hint_y: None
    height: 50
    markup: True

<MenuSpacer@Label>:
    size_hint_y: None
    height: 3
    canvas.before:
        Color:
            rgba: menucolor1
        Rectangle:
            pos: self.pos
            size: self.size
<MainPage>:
    canvas.before:
        Color:
            rgba: backgroundcolor
        Rectangle:
            pos: self.pos
            size: self.size
    name: 'main_screen'
    Label:
        color: menucolor1
        text: "Hi I'm Main Screen"

<AboutPage>:
    canvas:
        Color:
            rgba: backgroundcolor
        Rectangle:
            pos: self.pos
            size: self.size
    name: 'about_screen'
    Label:
        color: menucolor1
        text: "Hi I'm About Screen"


<MainContainer>:
    manager: manager
    canvas:
        Color:
            rgba: backgroundcolor
        Rectangle:
            pos: self.pos
            size: self.size
    BoxLayout:
        size: root.size
        orientation: 'horizontal'
        BoxLayout:
            orientation: 'vertical'
            width: 150
            size_hint_x: None
            MenuButton:
                text: '[b]Main[/b]'
                on_press: root.switch_to('main_screen')
            MenuSpacer:
            MenuButton:
                text: "[b]About[/b]"
                on_press: root.switch_to('about_screen')
            MenuSpacer:
            MenuButton:
                text: "[b]DummyConnect[/b]"
                on_press: root.dummyconnect()
            Widget:
                canvas.before:
                    Color:
                        rgba: menucolor1
                    Rectangle:
                        pos: self.pos
                        size: self.size
        ScreenManager:
            id:manager
            transition: CardTransition(direction='right',mode='push',duration=0.2)
            MainPage:
            AboutPage:

MainContainer.py

from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.app import App

class MainContainer(Widget):

    manager = ObjectProperty(None)

    def __init__(self, **kwargs):
        self.register_event_type('on_connect')
        super(MainContainer,self).__init__(**kwargs)
        print(self.children)

    def switch_to(self,name):
        self.manager.current = name

    def on_connect(self, *args):
        print("hello there")

    def dummyconnect(self):
        App.get_running_app().on_session("dummysession")

MainPage.py

from kivy.uix.screenmanager import Screen

class MainPage(Screen):
    pass

AboutPage.py

from kivy.uix.screenmanager import Screen

class AboutPage(Screen):
    pass

因此，基本上，我希望在MyApp中調度的on_connect事件傳播到MainPage和AboutPages，目前只有MainContainer定義了on_connect，但即使這樣也不會觸發。

我想我可以通過將其自己傳播給每個小部件的所有孩子來做到這一點，但是我還需要對所有的boxlayouts，screenmanagers和screen都實現它嗎？ 我認為有更好的方法可以做到這一點，但我還沒有找到。

任何幫助表示贊賞！

Answer 1

解

要將on_connect傳播到所有屏幕，即MainPage和AboutPage。 有關詳細信息，請參閱示例。

1. 為MainPage和AboutPage添加了ID
2. 將回調綁定到它們。 調度事件后，將使用與該特定事件相關的參數來調用您的回調。
3. return True ，表明我們已經消耗了觸摸並且不希望其進一步傳播。
4. 刪除了App（main.py）中的代碼，並在MainContainer.py中添加了一些代碼

注意

我已注釋掉return True以顯示事件傳播。 嘗試取消注釋return True以顯示傳播已停止。

片段

mainContainer上

def __init__(self, **kwargs):
    super(MainContainer, self).__init__(**kwargs)
    self.register_event_type('on_connect')
    print(self.children)
    self.bind(on_connect=self.ids.main_page.on_connect)
    self.bind(on_connect=self.ids.about_page.on_connect)
...
def on_connect(self, *args):
    print("\nMainContainer.on_connect()")
    print("hello there")
    # return True   # indicating that we have consumed the touch and don’t want it to propagate any further.

例

main.py

from kivy.app import App
from kivy.config import Config
from MainPage import MainPage
from AboutPage import AboutPage
from MainContainer import MainContainer


class MyApp(App):

    def build(self):
        return MainContainer()


if __name__ == "__main__":
    MyApp().run()

my.kv

#:kivy 1.10.1
#:import CardTransition kivy.uix.screenmanager.CardTransition
#:set menucolor1 0, 0.603, 0.784, 1
#:set menucolor2 0, 0.203, 0.384, 1
#:set backgroundcolor 0.95, 0.95, 0.95, 1

<MenuButton@Button>:
    size_hint_y: None
    height: 50
    markup: True

<MenuSpacer@Label>:
    size_hint_y: None
    height: 3
    canvas.before:
        Color:
            rgba: menucolor1
        Rectangle:
            pos: self.pos
            size: self.size
<MainPage>:
    canvas.before:
        Color:
            rgba: backgroundcolor
        Rectangle:
            pos: self.pos
            size: self.size
    name: 'main_screen'
    Label:
        color: menucolor1
        text: "Hi I'm Main Screen"

<AboutPage>:
    canvas:
        Color:
            rgba: backgroundcolor
        Rectangle:
            pos: self.pos
            size: self.size
    name: 'about_screen'
    Label:
        color: menucolor1
        text: "Hi I'm About Screen"


<MainContainer>:
    manager: manager
    canvas:
        Color:
            rgba: backgroundcolor
        Rectangle:
            pos: self.pos
            size: self.size
    BoxLayout:
        size: root.size
        orientation: 'horizontal'
        BoxLayout:
            orientation: 'vertical'
            width: 150
            size_hint_x: None
            MenuButton:
                text: '[b]Main[/b]'
                on_press: root.switch_to('main_screen')
            MenuSpacer:
            MenuButton:
                text: "[b]About[/b]"
                on_press: root.switch_to('about_screen')
            MenuSpacer:
            MenuButton:
                text: "[b]DummyConnect[/b]"
                on_press:
                    root.on_session()
            Widget:
                canvas.before:
                    Color:
                        rgba: menucolor1
                    Rectangle:
                        pos: self.pos
                        size: self.size
        ScreenManager:
            id: manager
            transition: CardTransition(direction='right',mode='push',duration=0.2)

            MainPage:
                id: main_page

            AboutPage:
                id: about_page

MainContainer.py

from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty


class MainContainer(Widget):

    manager = ObjectProperty(None)

    def __init__(self, **kwargs):
        super(MainContainer, self).__init__(**kwargs)
        self.register_event_type('on_connect')
        print(self.children)
        self.bind(on_connect=self.ids.main_page.on_connect)
        self.bind(on_connect=self.ids.about_page.on_connect)

    def switch_to(self, name):
        self.manager.current = name

    def on_connect(self, *args):
        print("\nMainContainer.on_connect()")
        print("hello there")
        # return True   # indicating that we have consumed the touch and don’t want it to propagate any further.

    def on_session(self):
        print("session connected!")
        self.dispatch('on_connect')

MainPage.py

from kivy.uix.screenmanager import Screen


class MainPage(Screen):

    def on_connect(self, *args):
        print("\nMainPage.on_connect()")
        # return True   # indicating that we have consumed the touch and don’t want it to propagate any further.

AboutPage

from kivy.uix.screenmanager import Screen


class AboutPage(Screen):

    def on_connect(self, *args):
        print("\nAboutPage.on_connect()")
        # return True   # indicating that we have consumed the touch and don’t want it to propagate any further.

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