我是Kivy的新手，我正在开发一款车辆维修跟踪应用程序，我有一个约会列表，当你按下列表上的项目时，我试图转到另一个屏幕，我不知道为什么它不适合我，因为它说它在另一个屏幕上，但它不在应用程序上
from kivymd.app import MDApp
from kivy.lang.builder import Builder
from kivymd.uix.list import ThreeLineAvatarIconListItem
from kivymd.uix.list import ImageLeftWidget
from kivy.uix.screenmanager import Screen, ScreenManager, SwapTransition, CardTransition
from kivy.core.window import Window
import sqlite3
DatabaseConnection = sqlite3.connect('CarWorkshopDB.db')
cursor = DatabaseConnection.cursor()
Window.size= (400, 650)
class MainScreen(Screen):
pass
class AddScreen(Screen):
pass
class DetailsScreen(Screen):
pass
class WorkApp(MDApp):
def build(self):
self.screen_manager = ScreenManager(transition=CardTransition())
self.screen_manager.add_widget(MainScreen(name='MainScreen'))
self.screen_manager.add_widget(AddScreen(name='AddScreen'))
self.screen_manager.add_widget(DetailsScreen(name='DetailsScreen'))
screen = Builder.load_file("test2.kv")
return screen
def on_start(self):
client = 'John smith'
cursor.execute("SELECT TrackingNumber, Plate, Status FROM Appointments WHERE Customer =?", (client,))
for i in cursor:
self.new_message(i[0], i[1], i[2])
def new_message(self, TrackingNumber, Vehicle, Process):
new_message = ThreeLineAvatarIconListItem(text=TrackingNumber, secondary_text=Vehicle, tertiary_text=Process)
new_message.add_widget(ImageLeftWidget(source='RepairIMG.jpg'))
new_message.bind(on_release=self.on_touch_down)
self.root.ids.list.add_widget(new_message)
def on_touch_down(self, x):
print(self.screen_manager.current)
self.screen_manager.current = "DetailsScreen"
self.screen_manager.transition.direction = 'right'
print(self.screen_manager.current)
WorkApp().run()
这是kv文件中的列表代码
NavigationLayout:
ScreenManager:
id: screen_manager
MainScreen:
name : "MainScreen"
BoxLayout:
orientation:'vertical'
MDBottomNavigation:
panel_color: 1, .643, 0, 1
MDBottomNavigationItem:
name: 'screen 1'
text: 'Home'
icon: 'alpha-h-circle'
MDToolbar:
title: 'Add Repair'
md_bg_color: 1, .643, 0, 1
elevation: 6
pos_hint: {'top':1}
Widget:
MDBottomNavigationItem:
name: 'screen 2'
text: 'Track'
icon: 'alpha-t-circle'
MDToolbar:
id: toolbar
title: 'Track History'
md_bg_color: 1, .643, 0, 1
elevation: 6
pos_hint: {'top':1}
NavigationLayout:
x: toolbar.height
size_hint_y: 1.0 - toolbar.height/root.height
ScreenManager:
Screen:
name: 'ScrollViewScreen'
ScrollView:
MDList:
id: list
MDFloatingActionButton:
icon: 'plus'
md_bg_color: 1, .643, 0, 1
on_release:
screen_manager.current = 'AddScreen'
screen_manager.transition = CardTransition()
screen_manager.transition.direction = "down"
pos_hint: {'x': .84, 'y': .02}
MDBottomNavigationItem:
name: 'screen 4'
text: 'More'
icon: 'dots-horizontal'
MDToolbar:
title: 'More'
md_bg_color: 1, .643, 0, 1
elevation: 6
pos_hint: {'top':1}
Widget:
MDLabel:
text: 'dfsfdsf'
halign: 'center'
AddScreen:
name: 'AddScreen'
id: Add
FloatLayout:
orientation: 'vertical'
MDToolbar:
id: toolbar2
title: 'Add Tracking Number'
md_bg_color: 1, .643, 0, 1
elevation: 6
pos_hint: {'top':1}
MDIconButton:
icon : 'close'
pos_hint : {'top':0.98, 'x':0.85}
on_release :
screen_manager.current = "Main"
screen_manager.transition = CardTransition()
screen_manager.transition.direction = "up"
FloatLayout:
x: toolbar2.height
size_hint_y: 1.0 - toolbar.height/root.height
ScatterLayout:
MDLabel:
text: 'Track Repair'
font_style: 'H4'
valign: 'top'
pos_hint: {'top':1}
text_size: self.size
size_hint: None, None
MDTextFieldRound:
icon_left: 'alpha-t-circle'
hint_text: 'Tracking Number'
normal_color: 1, .643, 0, 1
pos_hint: {'y':.7}
text_size: self.size
MDTextFieldRound:
icon_left: 'alpha-p-circle'
hint_text: 'Postcode'
normal_color: 1, .643, 0, 1
pos_hint: {'y':.6}
text_size: self.size
MDTextButton:
text: "Cant find your tracking number?"
custom_color: 1, .643, 0, 1
pos_hint: {'y':.5}
halign: 'center'
MDRectangleFlatButton:
text: 'confirm'
pos_hint: {'y':.4}
valign: 'middle'
text_size: self.size
DetailsScreen:
name: 'DetailsScreen'
id: Details
BoxLayout:
orientation: 'vertical'
MDLabel:
text: 'details Screen?'
问题是，在您的build()方法中，您正在构建以下行中的小部件树:
self.screen_manager = ScreenManager(transition=CardTransition())
self.screen_manager.add_widget(MainScreen(name='MainScreen'))
self.screen_manager.add_widget(AddScreen(name='AddScreen'))
self.screen_manager.add_widget(DetailsScreen(name='DetailsScreen'))
但是这个小部件树没有在GUI中使用。GUI中的小部件树是通过以下方式从kv文件构建的:
screen = Builder.load_file("test2.kv")
当你的代码试图改变当前的Screen使用:
self.screen_manager.current = "DetailsScreen"
它正在更改当前ScreenManager的Screen，不在您的GUI中。
self.screen_manager分配正确的值，像这样:
class WorkApp(MDApp):
def build(self):
screen = Builder.load_file("test2.kv")
self.screen_manager = screen.ids.screen_manager
return screen