【发布时间】：2017-10-06 08:23:57
【问题描述】：
我目前正在与 kivy 合作开发一个可以在多个屏幕上动态打印数字的应用程序。
现在正在从一个屏幕打印值，但我还必须在其他两个屏幕上显示值，问题是我正在调用一个类的方法以及时连续运行并更新变量值，我想要从其他类中的该方法查询或访问这些变量以在其他屏幕上打印它们，每个类都代表一个屏幕，因此它们必须存在于代码中。
我想知道这是否可行以及如何实施解决方案。
让我分享我的一段代码，它非常大，所以我只粘贴相关代码：
gui.py
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.properties import ObjectProperty, StringProperty, NumericProperty
from kivy.uix.gridlayout import GridLayout
from kivy.clock import Clock
# Creating dynamic variables
class Show_Val(Screen):
timer_update = NumericProperty(0)
dist_travel = NumericProperty(0)
average_mph = NumericProperty(0)
temp = NumericProperty(0)
dist_travel_2 = NumericProperty(0)
# screen 1: this is working ok
class Main_Screen(Screen):
update_val = Show_Val()
def update(self, dt):
# these corresponds to the screen 1, their are currently working
self.update_val.timer_update += 1
self.update_val.dist_travel += 1
self.update_val.average_mph += 1
# temp variable would be printed in screen 2: Input_Screen
self.update_val.temp += 1
# and dist_travel_2 will be printed in screen 3: Route_Screen
self.update_val.dist_travel_2 += 1
# screen 2: here I need to get access to self.update_val.temp
class Input_Screen(Screen):
pass
# screen 3: here I need to get access to self.update_val.temp
class Route_Screen(Screen):
pass
# screen 0 or master screen management, it's just for reference
class Screen_Management(ScreenManager):
pass
presentation = Builder.load_file("gui.kv")
class guiApp(App):
def build(self):
main = Main_Screen()
# this call is my "loop" and is updating the variables at 50hz
# frequency, I tried to call differently functions like this one
# but with no success.
Clock.schedule_interval(main.update, 1.0/50.0)
return presentation
guiApp().run()
gui.kv
Screen_Management:
id: screen_management
transition: FadeTransition()
Main_Screen:
id: main_screen
name: "main_screen_name"
manager: screen_management
Input_Screen:
id: tire_setup_screen_id
name: "tire_setup_screen_name"
manager: screen_management
Route_Screen:
name: "route_input_screen_name"
##############################################################
##############################################################
# Screen 1: Main Screen
# working ok
<Main_Screen>:
canvas:
Color:
rgb: [.30, .30, .30]
Rectangle:
pos: self.pos
size: self.size
BoxLayout:
orientation: 'vertical'
Button:
id: timer_indicator
background_disabled_down: ('0.00.00,000')
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 100
text: str(root.update_val.timer_update)
#text: root.update_val.test
pos_hint: {'x': .2}
size_hint: [.8, 1]
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 100
text: str(root.update_val.dist_travel)
pos_hint: {'x': .2}
size_hint: [.8, 1]
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 100
text: str(root.update_val.average_mph)
pos_hint: {'x': .2}
size_hint: [.8, 1]
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
size_hint: .2, 1
pos_hint: {"x": 0, "center_y": .5}
on_release: app.root.current = "tire_setup_screen_name"
text: " INPUTS "
font_size: 30
##############################################################
##############################################################
# Screen 2: Input Screen
# I will need to print self.update_val.temp value in this creen
<Input_Screen>:
canvas:
Color:
rgb: [.30, .30, .30]
Rectangle:
pos: self.pos
size: self.size
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 30
size_hint: 0.2, .5
text: "MAIN"
pos_hint: {'x':0, 'y': 0}
on_release: app.root.current = "main_screen_name"
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 30
size_hint: .2, .5
text: "ROUTES"
pos_hint: {'x':0, 'y': .5}
on_release: app.root.current = "route_input_screen_name"
GridLayout:
cols: 2
pos: (205,150)
size_hint: (.8, .75)
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 30
text: " TIRE\nTEMP (°C)"
size_hint_x: None
width: 150
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 100
text: "000.000" # self.update_val.temp value it will be here
##############################################################
##############################################################
# Screen 3: Route Screen
# self.update_val.dist_travel_2 will be printed in this screen
<Route_Screen>:
canvas:
Color:
rgb: [.30, .30, .30]
Rectangle:
pos: self.pos
size: self.size
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 30
size_hint: 0.2, .5
text: "INPUTS"
pos_hint: {'x':0, 'y': 0}
on_release: app.root.current = "tire_setup_screen_name"
BoxLayout:
orientation: 'vertical'
Button:
background_color: .52, .52, .52, 1
bold: 1
color: .0078,.67,.69,1
font_size: 50
text: "000.000 MPH" # self.update_val.dist_travel_2 value
pos_hint: {'x': .2}
size_hint: [.8, 1]
感谢您抽出宝贵时间，希望您能帮我解决这个问题。
如何从其他类中的一种方法访问变量？
【问题讨论】：
标签： python kivy kivy-language