Kivy ScreenManager根目錄大小問題

Question

我只是想設置我的菜單。我看起來很好，然後我發現了ScreenManager，並決定使用它是一件好事。所以我將我的代碼移植到一個新文件中來試用它，但是我的屏幕布局完全沒有了。

我想要什麼：

import kivy 
kivy.require('1.9.1') 
from kivy.app import App 
from kivy.uix.tabbedpanel import TabbedPanel 
from kivy.uix.tabbedpanel import TabbedPanelHeader 
from kivy.uix.floatlayout import FloatLayout 
from kivy.uix.button import Button 
from kivy.uix.label import Label 
from kivy.uix.image import Image 
from kivy.uix.widget import Widget 
from kivy.uix.popup import Popup 

class MainMenu(Widget): 
    pass 


class G_A_M_E_App(App): 
    def build(self): 
     return MainMenu() 

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

及其.kv文件

#:kivy 1.9.1 

<MainMenu>: 

FloatLayout: 
    width: root.width * 1/3 
    height: root.height * 1/2 
    center_x: root.width * 1/2 
    center_y: root.height * 1/2 

    canvas: 
     Color: 
      rgba: 0,0,1,.5 
     Rectangle: 
      size: self.size 
      pos: self.pos 



    Button: 

     size_hint: (.5, .10) 
     pos_hint: {'center_x': .5, 'center_y' : .90} 
     text: 'Play' 
     color: [1, 0, 0, 1] 

     font_size: self.height * 5/6 
     border: [25, 25, 25, 25] 



    Button: 

     size_hint: (.5, .10) 
     pos_hint: {'center_x': .5, 'center_y' : .70} 
     text: 'Load' 
     color: [1, 0, 0, 1] 

     font_size: self.height * 5/6 
     border: [25, 25, 25, 25] 


    Button: 

     size_hint: (.5, .10) 
     pos_hint: {'center_x': .5, 'center_y' : .50} 
     text: 'New Game' 
     color: [1, 0, 0, 1] 

     font_size: self.height * 5/6 
     border: [25, 25, 25, 25] 


    Button: 
     id: help 
     size_hint: (.5, .10) 
     pos_hint: {'center_x': .5, 'center_y' : .30} 
     text: 'Help' 
     color: [1, 0, 0, 1] 

     font_size: self.height * 5/6 
     border: [25, 25, 25, 25] 
     on_press: root.helpm() 


    Button: 

     size_hint: (.5, .10) 
     pos_hint: {'center_x': .5, 'center_y' : .10} 
     text: 'Quit' 
     color: [1, 0, 0, 1] 

     font_size: self.height * 5/6 
     border: [25, 25, 25, 25] 

1 和繼承人，這並不像她那樣

import kivy 
kivy.require('1.9.1') 
from kivy.app import App 
from kivy.lang import Builder 
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition 
from kivy.uix.floatlayout import FloatLayout 
from kivy.uix.button import Button 
from kivy.uix.label import Label 
from kivy.uix.image import Image 
from kivy.uix.widget import Widget 
from kivy.uix.popup import Popup 


class StartMenu(Screen): 
    pass 

class NewGame(Screen): 
    pass 

class LoadGame(Screen): 
    pass 

class ScreenManager(ScreenManager): 
    pass 




sm = Builder.load_file("main.kv") 

class G_A_M_E_App(App): 
    def build(self): 
     return sm 
if __name__=='main__': 
    G_A_M_E_App().run() 

及其.kv文件中的一個

ScreenManager: 
    StartMenu: 
    NewGame: 
    LoadGame: 

<StartMenu>: 
    name: 'start_menu' 

    FloatLayout: 
     width: root.width * 1/3 
     height: root.height * 1/2 
     center_x: root.width * 1/2 
     center_y: root.height * 1/4 

     canvas: 
      Color: 
       rgba: 0,0,1,.5 
      Rectangle: 
       size: root.size 
       pos: root.pos 



     Button: 

      size_hint: (.5, .10) 
      pos_hint: {'center_x': .5, 'center_y' : .90} 
      text: 'Play' 
      color: [1, 0, 0, 1] 
      font_size: self.height * 5/6 
      border: [25, 25, 25, 25] 



     Button: 

      size_hint: (.5, .10) 
      pos_hint: {'center_x': .5, 'center_y' : .70} 
      text: 'Load' 
      color: [1, 0, 0, 1] 
      font_size: self.height * 5/6 
      border: [25, 25, 25, 25] 


     Button: 

      size_hint: (.5, .10) 
      pos_hint: {'center_x': .5, 'center_y' : .50} 
      text: 'New Game' 
      color: [1, 0, 0, 1] 
      font_size: self.height * 5/6 
      border: [25, 25, 25, 25] 


     Button: 
      id: help 
      size_hint: (.5, .10) 
      pos_hint: {'center_x': .5, 'center_y' : .30} 
      text: 'Help' 
      color: [1, 0, 0, 1] 
      font_size: self.height * 5/6 
      border: [25, 25, 25, 25] 


<NewGame>: 
    name: 'new_game' 

    Button: 
     on_release: app.root.current = 'new' 
     text: 'New Game' 
     font_size: 50 

<LoadGame>: 
    name: 'load_game' 

    Button: 
     on_release: app.root.current = 'load' 
     text: 'Load' 
     font_size: 50 

我沒有給大小我仍然使其基於根改變的值，並且我不知道什麼是影響它。

Screenshot of menu。

Answer 1

屏幕管理器是相對佈局。這是發生了什麼。 https://kivy.org/docs/api-kivy.uix.relativelayout.html#kivy-uix-relativelayout-common-pitfalls

Answer 2

試着將你的按鈕的BoxLayout的內部。像這樣：

FloatLayout: 
    canvas: 
     Color: 
      rgba: 0,0,1,.5 
     Rectangle: 
      size: root.size 
      pos: root.pos 
    BoxLayout: 
     spacing: 20 
     orientation: 'vertical' 
     size_hint: (.5, .5) 
     pos_hint: {'center_x':.5, 'center_y':.5} 
     Button: 
     Button: