So, I wanted to create an app that created tasks/habits in kivy. Basically, there would be a screen that shows you your tasks/habits, and you could click on a button to take you to another screen to create a new task/habit. You would input information about the task/habit in that screen, and click the submit button. The submit button would add the task/habit to the first screen. However, when I run my code, it works the first time. I can go to the second screen, add my habit/code and then go back to the first screen. However, when I click the button on the first screen, it gives me an error.
The error being: kivy.uix.screenmanager.ScreenManagerException: No Screen with name "second".
Here is my code:
main.py:
from kivy.lang import Builder
from kivy.properties import ObjectProperty
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout
from kivy.uix.label import Label
from kivy.uix.widget import Widget
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.image import Image
from PIL import Image
import numpy as np
class FirstWindow(Screen):
def add_label(self, name, time, date):
label = Label(text= f' {name}, {time}, {date}')
self.ids.boxlayout.add_widget(label)
class SecondWindow(Screen):
a_task = False
a_habit = False
name = ""
time = ""
date = ""
def task_button(self):
self.a_task = True
self.a_habit = False
def habit_button(self):
self.a_habit = True
self.a_task = False
def submit_button(self):
self.name = self.ids.the_name.text
self.time = f'{self.ids.time_spinner_1.text}:{self.ids.time_spinner_2.text}'
self.date = f'{self.ids.date_spinner_1.text}/{self.ids.date_spinner_2.text}'
def get_name(self):
return self.name
def get_time(self):
return self.time
def get_date(self):
return self.date
kv = Builder.load_file('Button.kv')
class ButtonApp(App):
def build(self):
sm = ScreenManager()
sm.add_widget(FirstWindow())
sm.add_widget(SecondWindow())
return sm
if __name__ == '__main__':
ButtonApp().run()
Button.kv:
<FirstWindow>:
name: "first"
BoxLayout:
id: boxlayout
orientation: "vertical"
canvas.before:
Color:
rgba: (0.3,0.33,0.3,1)
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Label:
text: "To Do List"
font_size: 32
pos_hint: { 'right': 0.65, 'top': 1.4 }
Button:
text: "add a task"
on_release: root.manager.current = "second"
<SecondWindow>:
name: "second"
BoxLayout:
orientation: "vertical"
spacing: "10dp"
canvas.before:
Color:
rgba: (0.3,0.33,0.3,1)
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Label:
text: "Add A Task"
font_size: 32
pos_hint: { 'right': 0.65, 'top': 1.2 }
BoxLayout:
orientation: "horizontal"
Button:
text: "task"
on_press: root.task_button()
Button:
text: "habit"
on_press: root.habit_button()
TextInput:
id: the_name
text: "Name"
Label:
text: "alert"
BoxLayout:
orientation: "horizontal"
Spinner:
id: time_spinner_1
text: "00"
values: ['1','2','3','4','5','6','7','8','9','10','11', '12']
Spinner:
id: time_spinner_2
text: "00"
values: ['01','02','03','04','05','06','07','08','09','10','11', '12', '13','14','15','16','17','18','19','20','21','22','23','24','25','26','27','28','29','30','31','32','33','34','35','36','37','38','39','40','41','42','43','44','45','46','47','48','49','50','51','52','53','54','55','56','57','58','59']
BoxLayout:
orientation: "horizontal"
Spinner:
id: date_spinner_1
text: "00"
values: ['1','2','3','4','5','6','7','8','9','10','11', '12']
Spinner:
id: date_spinner_2
text: "00"
values: ['01','02','03','04','05','06','07','08','09','10','11', '12', '13','14','15','16','17','18','19','20','21','22','23','24','25','26','27','28','29','30','31']
Button:
text: "submit"
on_press: root.submit_button()
on_release:
root.manager.current = "first"
root.manager.get_screen("first").add_label(root.get_name(), root.get_time(), root.get_date())
Your code:
def submit_button(self):
self.name = self.ids.the_name.text
self.time = f'{self.ids.time_spinner_1.text}:{self.ids.time_spinner_2.text}'
self.date = f'{self.ids.date_spinner_1.text}/{self.ids.date_spinner_2.text}'
changes the name property of the SecondWindow Screen, so trying to change Screen to the second will no longer work. It looks like you are trying to use name for some other purpose. I suggest you use a variable with a different name.
I have a problem with my Kivy Python Code. I have 2 screens: 1st is to navigate to the second screen and on the 2nd screen there is a button to add text to a scrollview...navigating is working but it does not add any text to the scrollview...I think I need some help here! AttributeError: 'super' object has no attribute 'getattr'
import kivy
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.gridlayout import GridLayout
from kivy.uix.textinput import TextInput
from kivy.uix.button import Button
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.clock import Clock, mainthread
from kivy.core.window import Window
from kivy.uix.scrollview import ScrollView
from kivy.effects.scroll import ScrollEffect
from kivy.lang import Builder
Builder.load_string("""
<MenuScreen>:
name: 'mainmenu'
BoxLayout:
spacing: 1
orientation: "vertical"
Label:
text: "MAIN MENU"
Button:
text: 'Go to Screen 2'
on_release:
root.manager.current = 'screen2'
root.manager.transition.direction = "left"
Button:
text: 'Quit'
on_release: root.manager.current = app.exit_software()
<Screen2>:
name: 'screen2'
BoxLayout:
spacing: 1
orientation: "vertical"
ScrollView:
id: scroll_view
always_overscroll: False
BoxLayout:
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
Label:
id: label
text: "You can add some Text here by pressing the button"
size_hint: None, None
size: self.texture_size
Button:
text: 'Add text!'
size_hint_y: 0.1
on_release: app.add_text()
Button:
text: 'Back to main menu'
size_hint_y: 0.1
on_release:
root.manager.current = 'mainmenu'
root.manager.transition.direction = "right"
""")
# Declare both screens
class MenuScreen(Screen):
pass
class Screen2(Screen):
pass
class AddTextApp(App):
def __init__(self,**kwargs):
super().__init__(**kwargs)
def build(self):
# Create the screen manager
sm = ScreenManager()
sm.add_widget(MenuScreen(name='mainmenu'))
sm.add_widget(Screen2(name='screen2'))
return sm
def add_text(self):
self.root.ids.label.text += f"Some new Text\n"
self.root.ids.scroll_view.scroll_y = 0
def exit_software(self):
App.get_running_app().stop()
if __name__ == '__main__':
AddTextApp().run()
Thank you very much in advance!
The error occurred because self.root.ids gets access to widgets located in the root widget of the main class. To access the secondary screen elements, you need to add it to the main class (in your case, in ScreenManager) and set its id. Also, you have a lot of imported excess, so that it is clearly visible, I advise you to use Pycharm or something like that.
from kivy.app import App
from kivy.uix.screenmanager import Screen
from kivy.lang import Builder
kv = """
<MenuScreen>:
name: 'mainmenu'
BoxLayout:
spacing: 1
orientation: "vertical"
Label:
text: "MAIN MENU"
Button:
text: 'Go to Screen 2'
on_release:
root.manager.current = 'screen2'
root.manager.transition.direction = "left"
Button:
text: 'Quit'
on_release: root.manager.current = app.exit_software()
<Screen2>:
name: 'screen2'
BoxLayout:
spacing: 1
orientation: "vertical"
ScrollView:
id: scroll_view
always_overscroll: False
BoxLayout:
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
Label:
id: label
text: "You can add some Text here by pressing the button"
size_hint: None, None
size: self.texture_size
Button:
text: 'Add text!'
size_hint_y: 0.1
on_release: app.add_text()
Button:
text: 'Back to main menu'
size_hint_y: 0.1
on_release:
root.manager.current = 'mainmenu'
root.manager.transition.direction = "right"
ScreenManager:
MenuScreen:
id: menu_scr
Screen2:
id: scr_2
"""
class MenuScreen(Screen):
pass
class Screen2(Screen):
pass
class AddTextApp(App):
def __init__(self, **kwargs):
super().__init__(**kwargs)
def build(self):
return Builder.load_string(kv)
def add_text(self):
self.root.ids.scr_2.ids.label.text += f"Some new Text\n"
self.root.ids.scr_2.ids.scroll_view.scroll_y = 0
#staticmethod
def exit_software():
App.get_running_app().stop()
if __name__ == '__main__':
AddTextApp().run()
I am currently building a mobile app with kivy. In one of my screens I am trying to include an MDExpansionPanel, although I have tried with a lot of different codes, and searched on the web for solutions, either I get an error, or simply the Expansion Panel is not rendered in my screen. I am using ScreenManager since I have 5 screens, with the possibility of increasing such number.
The relevant Python code is the following:
from kivy.app import App
from kivy.properties import ObjectProperty
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.screenmanager import ScreenManager, Screen
from kivymd.app import MDApp
from kivymd.theming import ThemeManager
from kivymd.toast import toast
from kivymd.uix.picker import MDDatePicker, MDTimePicker
from kivymd.uix.expansionpanel import MDExpansionPanel
from kivymd.uix.boxlayout import MDBoxLayout
class LoginWindow(Screen):
pass
class CreateAccountWindow(Screen):
pass
class MainWindow(Screen):
pass
class TravelManagerWindow(Screen):
pass
class IngActivWindow(Screen):
panel_container = ObjectProperty(None)
def on_pre_enter(self, *args):
self.add_panels()
def show_timepicker(self):
picker = MDTimePicker()
picker.bind(time=self.got_time)
picker.open()
def got_time(self, picker_widget, time):
self.text = str(time.hour) + ":" + str(time.minute)
self.focus = False
# selectedTime= self.text
print(self.text)
self.ids.tiempoActiv.text = self.text
def add_panels(self):
for i in range(5):
IngActivWindow.ids.panel_container.add_widget(
MDExpansionPanel(
icon="actividades.png",
content=MyContent(),
panel_cls=MDExpansionPanelOneLine(
text="Text",
)
)
)
class MyContent(MDBoxLayout):
pass
class WindowManager(ScreenManager):
ScreenManager().add_widget(LoginWindow(name='login'))
ScreenManager().add_widget(CreateAccountWindow(name='create'))
ScreenManager().add_widget(MainWindow(name='main'))
ScreenManager().add_widget(IngActivWindow(name='ingActiv'))
ScreenManager().add_widget(TravelManagerWindow(name='travelManager'))
class powerApp1(MDApp):
def build(self):
self.theme_cls.primary_palette = "Teal"
return WindowManager()
if __name__ == "__main__":
powerApp1().run()
The relevant kv code is the following:
(I have an image on the background and an Action Bar before the MDBoxLayout where I am trying to add the Expansion Panel)
<WindowManager>:
LoginWindow:
CreateAccountWindow:
MainWindow:
IngActivWindow:
TravelManagerWindow:
<IngActivWindow>:
name: 'ingActiv'
panel_container: panel_container
FloatLayout:
cols:1
canvas.before:
Rectangle:
pos: self.pos
size: self.size
source: 'ingActiv_background.png'
ActionBar:
pos_hint: {'top':1}
ActionView:
use_separator: True
ActionPrevious:
title: '---------'
with_previous: False
ActionButton:
icon: 'homeIcon.png'
on_press:
root.manager.current = 'main'
root.manager.transition.direction = 'right'
ActionGroup:
text: 'Gastos de Viaje'
mode: 'spinner'
size_hint:(None,None)
size: root.width/5,root.height/12
ActionButton:
text: 'Solicitar'
on_release:
root.manager.current = 'solicitud'
root.manager.transition.direction = 'left'
ActionButton:
text: 'Comprobar'
on_release:
root.manager.current = 'comprobar'
root.manager.transition.direction = 'left'
ActionGroup:
text: 'Opciones'
mode: 'spinner'
size_hint:(None,None)
size: root.width/5,root.height/12
ActionButton:
text: 'Ingresar Actividad'
on_release:
root.manager.current = 'ingActiv'
root.manager.transition.direction = 'left'
ActionButton:
text: 'Enviar Reporte'
ActionButton:
text: 'Cerrar Sesion'
on_release:
root.manager.current = 'login'
root.manager.transition.direction = 'down'
MDBoxLayout:
cols:1
size_hint: 1,0.6
pos_hint: {"center_x": 0.5, "center_y": 0.5}
ScrollView:
GridLayout:
id: panel_container
cols: 1
pos_hint: {"center_x": 0.5, "center_y": 0.5}
<MyContent>:
size_hint: 1, None
height: self.minimum_height
orientation: 'horizontal'
Button:
size_hint: None, None
Thanks a lot in advance for your support,
Have a great day.
I'm looking for a way to change a part of a screen between 'DownPanel1' and 'DownPanel1' but I would like to avoide creating nex screen class 'ToAvoid'. Is it possible?
from kivy.config import Config
Config.set('graphics', 'multisamples', '0')
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.boxlayout import BoxLayout
kv = '''
#:import FadeTransition kivy.uix.screenmanager.FadeTransition
ScreenManagement:
transition: FadeTransition()
SomeScreen:
ToAvoid:
<Menu#RelativeLayout>
id: main_menu
size_hint_x: None
width: 120
Button:
size_hint_y: None
pos: root.x, root.top - self.height
text: 'SomeScreen'
on_press: app.root.current = "SomeScreen"
<UpScreen>:
BoxLayout:
Button:
text: 'switch'
on_press: app.root.current = "ToAvoid"
<DownPanel1>:
Button:
text: 'DownPanel1'
#on_press:
<DownPanel2>:
Button:
text: 'DownPanel2'
#on_press:
<SomeScreen>:
name: 'SomeScreen'
BoxLayout:
orientation: 'horizontal'
Menu:
BoxLayout:
orientation: 'vertical'
UpScreen:
DownPanel1:
<ToAvoid>:
name: 'ToAvoid'
BoxLayout:
orientation: 'horizontal'
Menu:
BoxLayout:
orientation: 'vertical'
UpScreen:
DownPanel2:
'''
class DownPanel1(BoxLayout):
pass
class DownPanel2(BoxLayout):
pass
class UpScreen(Screen):
pass
class SomeScreen(Screen):
pass
class ToAvoid(Screen):
pass
class ScreenManagement(ScreenManager):
pass
sm = Builder.load_string(kv)
class TestApp(App):
def build(self):
return sm
if __name__ == '__main__':
TestApp().run()
How about some inception? Just put another ScreenManager inside of the other.
Try this example:
from kivy.app import App
from kivy.lang import Builder
KV = """
ScreenManager:
Screen:
name: "1st"
Button:
text: "next"
on_release:
root.current = "2nd"
Screen:
name: "2nd"
BoxLayout:
Button:
text: "3rd to avoid"
on_release:
root.current = "3rd"
ScreenManager:
id: sm2
Screen:
name: "inner1"
Button:
text: "go to inner 2"
on_release:
sm2.current = "inner2"
Screen:
name: "inner2"
Label:
text: "This is inner 2!"
Screen:
name: "3rd"
Label:
text: "To Avoid!"
"""
class MyApp(App):
def build(self):
return Builder.load_string(KV)
if __name__ == "__main__":
MyApp().run()
After much headbanging, I've created an app that opens the FileChooser and picks an image. A function will then transform the image and change it on the screen.
< FirstScreen > is just something to start with, relatively unimportant.
< SecondScreen > is the file chooser. The path may need editing. < ThirdScreen > shoudl show the image along with buttons that will eventually lead elsewhere.
I suspect the problem is that the line
sm.current = "_third_screen_"
is creating a new instance separate to everything else I've passed items too. How do I show the image I selected?
from kivy.lang import Builder
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.properties import ObjectProperty, StringProperty
Builder.load_string("""
<MyScreenManager>:
FirstScreen:
SecondScreen:
ThirdScreen:
<FirstScreen>:
name: '_first_screen_'
BoxLayout:
orientation: "horizontal"
Label:
id: first_screen_label
text: "Hi, I'm the home page"
BoxLayout:
orientation: "vertical"
Button:
text: "Okay!"
on_press: root.manager.current = '_second_screen_'
Button:
text: "Cancel!"
on_press: app.stop()
<SecondScreen>:
name: '_second_screen_'
id: file_chooser
BoxLayout:
id: file_chooser_box_layout
orientation: "horizontal"
Button
text: "Open"
on_press:
root.callback_image_and_other_stuff(file_chooser_list_view.selection)
FileChooserListView:
id: file_chooser_list_view
<ThirdScreen>:
name: '_third_screen_'
BoxLayout:
orientation: "vertical"
id: third_screen
Label:
id: main_title
text: "Upload"
size_hint: (1, 0.1)
Image:
id: main_image
source: root.img
size_hint: (1, 0.75)
BoxLayout:
orientation: "horizontal"
padding: 10
size_hint: (1, 0.15)
Button:
text: "Okay"
size_hint: (0.5, 1)
on_press: image_viewer.image_accepted_by_user(filechooser.selection)
Button:
text: "Cancel"
size_hint: (0.5, 1)
on_press: root.manager.current = '_first_screen_'
""")
class FirstScreen(Screen):
pass
class SecondScreen(Screen):
def callback_image_and_other_stuff(self, new_image_address):
# do other stuff here also, then pass new_image_address along
new_image_address = new_image_address[0].replace("\\", "/")
third_screen = ThirdScreen()
third_screen.callback_image(new_image_address)
class ThirdScreen(Screen):
img = ObjectProperty(None)
def __init__(self, **kwargs):
super(Screen, self).__init__(**kwargs)
def callback_image(self, new_image_address):
sm.current = "_third_screen_"
self.img = new_image_address
self.ids.main_image.source = self.img
print(self.img)
# Create the screen manager
sm = ScreenManager() # Problem?
sm.add_widget(FirstScreen(name='_first_screen_'))
sm.add_widget(SecondScreen(name='_second_screen_'))
sm.add_widget(ThirdScreen(name='_third_screen_'))
class MyApp(App):
def build(self):
return sm
if __name__ == '__main__':
MyApp().run()
Every time you use some_obj = SomClass() you are creating a new object, in your case that is what you are doing, you are creating a new ThirdScreen different from the one shown by that you do not observe the image, the solution is that you have to access to the initial object using the ScreenManager and name screen.
from kivy.lang import Builder
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.properties import ObjectProperty, StringProperty
Builder.load_string("""
<FirstScreen>:
BoxLayout:
orientation: "horizontal"
Label:
id: first_screen_label
text: "Hi, I'm the home page"
BoxLayout:
orientation: "vertical"
Button:
text: "Okay!"
on_press: root.manager.current = '_second_screen_'
Button:
text: "Cancel!"
on_press: app.stop()
<SecondScreen>:
id: file_chooser
BoxLayout:
id: file_chooser_box_layout
orientation: "horizontal"
Button
text: "Open"
on_press:
root.callback_image_and_other_stuff(file_chooser_list_view.selection)
FileChooserListView:
id: file_chooser_list_view
<ThirdScreen>:
BoxLayout:
orientation: "vertical"
id: third_screen
Label:
id: main_title
text: "Upload"
size_hint: (1, 0.1)
Image:
id: main_image
source: root.img
size_hint: (1, 0.75)
BoxLayout:
orientation: "horizontal"
padding: 10
size_hint: (1, 0.15)
Button:
text: "Okay"
size_hint: (0.5, 1)
on_press: image_viewer.image_accepted_by_user(filechooser.selection)
Button:
text: "Cancel"
size_hint: (0.5, 1)
on_press: root.manager.current = '_first_screen_'
""")
class FirstScreen(Screen):
pass
class SecondScreen(Screen):
def callback_image_and_other_stuff(self, new_image_address):
if new_image_address:
third_screen = self.manager.get_screen("_third_screen_")
# do other stuff here also, then pass new_image_address along
new_image_address = new_image_address[0].replace("\\", "/")
third_screen.callback_image(new_image_address)
class ThirdScreen(Screen):
img = ObjectProperty(None)
def __init__(self, **kwargs):
super(Screen, self).__init__(**kwargs)
def callback_image(self, new_image_address):
sm.current = "_third_screen_"
self.img = new_image_address
self.ids.main_image.source = self.img
print(self.img)
# Create the screen manager
sm = ScreenManager() # Problem?
sm.add_widget(FirstScreen(name='_first_screen_'))
sm.add_widget(SecondScreen(name='_second_screen_'))
sm.add_widget(ThirdScreen(name='_third_screen_'))
class MyApp(App):
def build(self):
return sm
if __name__ == '__main__':
MyApp().run()