Kivy ScreenManager 打破 BoxLayout

Question

我是 Kivy 的新手，但能够创建单屏应用。在我需要添加更多屏幕之前，一切看起来都很好。一页应用程序显示正确，但是当我添加屏幕时，BoxLayouts 不再按预期工作。小部件全部呈现在屏幕底部。我的问题是我在实施 ScreenManager 时做错了什么？

单屏应用如下所示：

我决定让它多屏，但是当我添加 ScreenManager 逻辑时，生成的屏幕如下所示：

我从this tutorial获取信息

我的 main.py 文件如下所示：

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.uix.popup import Popup
from kivy.properties import ObjectProperty
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition

class Pay_screen(Screen):
    pass

class Survey_screen(Screen):
    pass

class Finish_screen(Screen):
    pass

class Sm(ScreenManager):
    pass

class Next_root(BoxLayout):
    pass

class Nq_disagree_label(Label):
    pass

class Nq_question_label(Label):
    pass

class Nq_button(Button):
    pass

class survey_form(BoxLayout):
    #dept_button = ObjectProperty()

    def send_survey(self):
        mypopup = MyPopup()
        mypopup.show_popup('Survey', 'Survey sent!', 'OK!')

    def add_comment(self):
        mypopup = MyPopup()
        mypopup.show_popup('Comment', 'This is where a comment is added.', 'OK!')

    def close_app(self):
        App.get_running_app().stop()

class MyPopup(Popup):
    def show_popup(self, title_text, label_text, button_text):
        mytext= label_text
        content = BoxLayout(orientation="vertical")
        content.add_widget(Label(text=mytext, font_size=20, text_size=(300, None)))
        mybutton = Button(text="Ok!", size_hint=(1,.20), font_size=20)
        content.add_widget(mybutton)
        mypopup = Popup(content = content,              
                        title = title_text,     
                        auto_dismiss = False,         
                        size_hint = (.5, .5)) #,         
                        #font_size = 20)
        mybutton.bind(on_press=mypopup.dismiss)  
        mypopup.open()  

class nextqualApp(App):
    icon = 'nextqual.png'
    title = 'Pay / survey / join'


if __name__ == '__main__':

    nextqualApp().run()

我的屏幕管理器的 KV 文件如下所示：

#: import FadeTransition kivy.uix.screenmanager.FadeTransition

Sm:
    transition: FadeTransition()
    Survey_screen:
    Pay_screen:


<nq_button@Button>:
    halign: "center"
    text: "Add\ncomment"
    size_hint_x: 10

<Nq_disagree_label@Label>:
    halign: "left"
    size_hint_x: 10
    text:"Strongly\ndisagree"

<Nq_agree_label@Label>:
    halign: "left"
    size_hint_x: 10
    text:"Strongly\nagree"

<Nq_question_label@Label>:
    halign: "left"
    font_size: "24"
    size_hint_x: 25

<Pay_screen>:
    name: 'pay'
    #orientation: "vertical"
    #padding: 6
    #font_size: 24
    BoxLayout:
        height: "40dp"
        Button: 
            text: "Pay your bill"
            on_release: app.root.current = 'pay'
        Button:
            text: "Tell us how we did"
            on_release: app.root.current = 'survey'
        Button:
            text: "I'm finished"
    BoxLayout:
        Button:
            text: "Pay your bill"
            on_release: app.root.current = 'survey'

<Survey_screen>:
    name: "survey"
    #orientation: "vertical"
    #padding: 6
    #font_size: "24"

    BoxLayout:
        height: "40dp"
        Button: 
            text: "Pay your bill"
            on_release: app.root.current = 'pay'

        Button:
            text: "Tell us how we did"
            on_release: app.root.current = 'survey'
        Button:
            text: "I'm finished"

    BoxLayout:
        halign: "center"
        Image:
            source: "logo.jpg"  
            #size: self.size

    BoxLayout:
        height: "80dp"
        size_hint_y: None
        Label:
            bold: True
            #color: 10,10,10,10
            #halign: "center"
            #text_size: self.size
            markup: True
            text: "[color=f9f752]Description[/color]"
            multiline: True
            #size_hint_x: 25
            text_size: self.size
            halign: 'center'
            valign: 'middle'


    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The service I recieved from start to finish was excellent."

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "I waited an appropriate amount of time for my food and drink."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()


    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The quality and presentation of the food was outstanding."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()


    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The prices provide good value for money."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The atmosphere was relaxing and enjoyable."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The overall cleanliness was very acceptable."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "I will recommend Synterest to my friends and family."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()


    BoxLayout:
        height: "100dp"
        size_hint_y: None

        Label:
            size_hint_x: 40
        Button:
            size_hint_x: 20
            text:"Send survey"
            halign: "center"
            on_press: root.send_survey()
        Label:
            size_hint_x: 40

没有屏幕管理器的KV文件是这样的：

nq_button@Button>:
    halign: "center"
    text: "Add\ncomment"
    size_hint_x: 10

<Nq_disagree_label@Label>:
    halign: "left"
    size_hint_x: 10
    text:"Strongly\ndisagree"

<Nq_agree_label@Label>:
    halign: "left"
    size_hint_x: 10
    text:"Strongly\nagree"

<Nq_question_label@Label>:
    halign: "left"
    font_size: "24"
    size_hint_x: 25

survey_form:

<survey_form>:
    name: "survey"
    orientation: "vertical"
    padding: 6
    font_size: "24"

    BoxLayout:
        height: "40dp"
        Button: 
            text: "Pay your bill"
            on_release: app.root.current = 'pay'

        Button:
            text: "Tell us how we did"
            on_release: app.root.current = 'survey'
        Button:
            text: "I'm finished"

    BoxLayout:
        halign: "center"
        Image:
            source: "logo.jpg"  
            #size: self.size

    BoxLayout:
        height: "80dp"
        size_hint_y: None
        Label:
            bold: True
            #color: 10,10,10,10
            #halign: "center"
            #text_size: self.size
            markup: True
            text: "[color=f9f752]At Synterest, we care deeply about your impressions of our food, service and atmosphere. We would be very grateful if you took a few moments to give us your feedback on how you enjoyed your meal.[/color]"
            multiline: True
            #size_hint_x: 25
            text_size: self.size
            halign: 'center'
            valign: 'middle'


    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The service I recieved from start to finish was excellent."

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "I waited an appropriate amount of time for my food and drink."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()


    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The quality and presentation of the food was outstanding."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()


    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The prices provide good value for money."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The atmosphere was relaxing and enjoyable."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "The overall cleanliness was very acceptable."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()

    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_question_label:
            text: "I will recommend Synterest to my friends and family."
    BoxLayout:
        height: "40dp"
        size_hint_y: None
        Nq_disagree_label:
        Slider:
            size_hint_x: 80
            value: 50
        Nq_agree_label:
        nq_button:
            on_press: root.add_comment()


    BoxLayout:
        height: "100dp"
        size_hint_y: None

        Label:
            size_hint_x: 40
        Button:
            size_hint_x: 20
            text:"Send survey"
            halign: "center"
            on_press: root.send_survey()
        Label:
            size_hint_x: 40

Answer 1

在这件事上挥汗如雨后，有时答案就变得显而易见了。

Survey_screen 和 Pay_screen 继承自 Main.py 文件中的 Screen。当我制作原始的一页应用程序时，根小部件继承自 BoxLayout。

我在 .kv 文件中的每个屏幕上添加了一个 BoxLayout 并将所有内容放在正确的位置。

例如，

<Survey_screen>:
    name: "survey"
    BoxLayout:
        orientation: "vertical"
        padding: 6
        BoxLayout:
            height: "40dp"
            size_hint_y: None

            Button: 

等

Answer 2

我已经设法让屏幕管理器工作，并在各个平台共享小部件属性 所有屏幕。

class XDispLayout(Screen):

    intr_str01 = str('This application advises --')


    def start01_value(self):

      xclr=[random.random(), random.random(), random.random()]+[1]

      self.ids.x1.color=xclr
      self.ids.set_ipbtn.color=xclr
      app = App.get_running_app()
      print ('text imported is '+ str(app.INT_TEXT))
      app.INT_TEXT = app.INT_TEXT + 1

      app.COLOR_STX=xclr
      print ('screen-Main app.COLOR_STX -is >'+ str(app.COLOR_STX))
      self.ids.ip_add01.color=app.COLOR_STX
      #below is an example of how you update on another screen, Year05 screen for eg.
      app.root.pyear05.ids.sfayear05.color =app.COLOR_STX

      return()

class Year01(Screen):
    def set_chk_same_cshint_y1(self,guess, *arg):
        if guess.active:
           temp_int=float(self.ids.cshint_y1m1.value)
           print ('tttt-is >'+ str(temp_int))
           app = App.get_running_app()
           self.ids.sfayear06.color=app.COLOR_STX
           print ('app.root.pyear01.ids.int_ylm2.value -is >'+ str(app.root.pyear01.ids.int_ylm1.value))
           #since the above is actually the same object, you can use 
           #different ways....
           #self.ids.int_ylm1.value==temp_int
           #app.root.pyear01.ids.int_ylm1.value=temp_int



class CManager(ScreenManager):
      #below is important when you want to change something on another screen
      pmain = ObjectProperty(None)
      pyear01 = ObjectProperty(None)
      pyear02 = ObjectProperty(None)
      pyear03 = ObjectProperty(None)
      pyear04 = ObjectProperty(None)
      pyear05 = ObjectProperty(None)
      pyear06 = ObjectProperty(None)
      #self.transition=NoTransition()
      pass


class FinDispApp(App):

  # the below values can be accessed using app.INT_TEXT, app.COLOR_STX
  INT_TEXT = 55
  COLOR_STX = [1,0,0,1]
  CASHOUT_00=0

  #.....
  #.......

   def build(self):
      sm = CManager(transition=NoTransition())
      sm.current='main'
      return sm


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



<CManager>:
    #this is the root widget
    id:screen_manager01
    #below maps python object property to kivy Ids
    pmain : idmain
    pyear01 : idyear01
    pyear02 : idyear02
    pyear03 : idyear03
    pyear04 : idyear04
    pyear05 : idyear05
    pyear06 : idyear06

    XDispLayout:
        id:idmain
        name:'main'
        manager:screen_manager01
    Year01:
        id:idyear01
        name:'year01'
        manager:screen_manager01
    Year02:
        id:idyear02
        name:'year02'
        manager:screen_manager01
    Year03:
        id:idyear03 
        name:'year03'
        manager:screen_manager01
    Year04:
        id:idyear04
        name:'year04'
        manager:screen_manager01
    Year05:
        id:idyear05
        name:'year05'
        manager:screen_manager01
    Year06:
        id:idyear06
        name:'year06'
        manager:screen_manager01

<XDispLayout>:
    name: 'main'
    orientation: "horizontal"
    BoxLayout:
        orientation:'vertical'


        BoxLayout:
            orientation:'horizontal'
            size_hint_x :1
            size_hint_y :0.08
            Button:
                id: btn_yr06
                text:'go to year06'
                o#pacity : 0
                #disabled : True
                on_press:
                    #root.setvalue_00()
                on_release:
                    root.manager.current = 'year06'
                    root.manager.transition.direction = 'right'               
            Button:
                id: btn_yr01
                text:'go to year01'
                opacity : 0
                disabled : True
                on_press:
                    #root.enable_y06()
                    #root.setvalue_00()
                on_release:
                    root.manager.current = 'year01'
                    root.manager.transition.direction = 'left'


<Year01>:
    name: 'year01'
    BoxLayout:
        orientation:'vertical'
        Label:
            id:sfayear01
            text: "Year01"


<Year02>:
    name: 'year02'
    BoxLayout:
        orientation:'vertical'
        Label:
            id:sfayear02
            text: "Year02"
            halign : 'right'
            valign : 'middle'


<Year06>:
    name: 'year06'
    BoxLayout:
        orientation:'vertical'
        Label:
            id:sfayear06
            text: "blah blah blas"
            font_size: 20

        BoxLayout:
            orientation:'horizontal'
        BoxLayout:
            orientation:'horizontal'
            size_hint_x :1
            size_hint_y :0.4
            Button:
                text:'go to year05'
                on_press:
                    root.manager.current = 'year05'
                    root.manager.transition.direction = 'right'
            Button:
                text:'go to main'
                on_press:
                    root.manager.current = 'main'
                    root.manager.transition.direction = 'left'