Issue
Good evening. I'm learning kivy and trying to make something like "microsoft to do". But I have a problem. Now I'm doing an adding task function. The main idea of it:
- When I click "add task"(button with plus icon) button, my screen changes on "AddingNewTaskScreen".
- In AddingNewTaskScreen class I created a function ""addTask that takes text from TextInput and add it in text file. Then it changes this screen on "MainMenuScreen"
- In MainMenuScreen class(it is first screen), in constructor i call a "taskRead" function that takes text from text file and write it in array. Then it adds elements of arrays in MDList and after it, it adds this MDList to ScrollView.
And it works, but it takes shows me tasks after new programm launch. For example: I add the task and the "MainMenuScreen" doesn't show me anything. But when I restart my programm, everything are in ScrollView. If you have any ideas how it can be fixed, please tell me, I wold really apreciate it. Thank you for advance.
main.py
from kivy.uix.button import Button
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.core.window import Window
from kivy.uix.widget import Widget
from kivymd.app import MDApp
from kivymd.uix.list import OneLineListItem, MDList
from kivy.properties import ObjectProperty
from kivy.uix.scrollview import ScrollView
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
class MainMenuScreen(Screen):
listBox = ObjectProperty()
theme_changer = ObjectProperty()
search_task = ObjectProperty()
all_tasks = ObjectProperty()
important_tasks = ObjectProperty()
create_list = ObjectProperty()
completed_tasks = ObjectProperty()
list_name = ObjectProperty()
sort = ObjectProperty()
rename = ObjectProperty()
add_button = ObjectProperty()
scroll = ScrollView()
list_view = MDList()
def __init__(self, **kw):
super().__init__(**kw)
self.taskRead()
def taskRead(self):
sv = open('tasks.txt', 'r', encoding='utf-8')
arr = sv.read().split('\n')
sv.close()
for i in range(len(arr)):
self.list_view.add_widget(OneLineListItem(text=arr[i], on_press=self.scr))
self.add_widget(MDList())
self.scroll.add_widget(self.list_view)
self.listBox.add_widget(self.scroll)
def scr(self, value):
self.manager.transition = FadeTransition()
self.manager.current = 'goodbye_screen'
class ToDoListApp(MDApp):
def __init__(self, **kw):
super().__init__(**kw)
def build(self):
self.theme_cls.theme_style = "Dark"
Window.size = (1300, 700)
sm = ScreenManager()
sm.add_widget(MainMenuScreen(name='main_menu_screen'))
sm.add_widget(ImportantOrCompletedTaskCheckScreen(name='goodbye_screen'))
sm.add_widget(AddingNewTaskScreen(name='adding_newTask_screen'))
return sm
class AddingNewTaskScreen(Screen):
taskToTxt = ObjectProperty()
addTaskButton = ObjectProperty()
def __init__(self, **kw):
super().__init__(**kw)
def addTask(self):
task_text = str(self.taskToTxt.text)
sv = open('tasks.txt', 'a', encoding='utf-8')
sv.writelines(str(task_text) + '\n')
sv.close()
ToDoListApp.get_running_app().root.current = "main_menu_screen"
# Class for another problem
class ImportantOrCompletedTaskCheckScreen(Screen):
pass
if __name__ == '__main__':
ToDoListApp().run()
todolist.kv
<MainMenuScreen@Screen>:
listBox:listBox
rename:rename
search_task:search_task
theme_changer:theme_changer
all_tasks:all_tasks
important_tasks:important_tasks
create_list:create_list
completed_tasks:completed_tasks
list_name:list_name
sort:sort
#add_button:add_button
orientation: 'vertical'
# right lateral panel
BoxLayout:
BoxLayout:
size_hint: '0.3', '0.8'
pos_hint: {'y': 0.17}
orientation: 'vertical'
GridLayout:
cols: 1
rows: 9
MDRoundFlatButton:
id: theme_changer
size_hint: 0.5, 0.3
text: 'Light theme'
line_color: 1,1,1,1
elevation_normal: 0
on_press: root.change_theme()
BoxLayout:
size_hint: 1, 0.5
MDRoundFlatButton:
size_hint: 1, 0.7
text: 'All tasks'
line_color: 1,1,1,1
id: all_tasks
BoxLayout:
size_hint: 1, 0.08
MDRoundFlatButton:
size_hint: 1, 0.7
text: 'Important'
line_color: 1,1,1,1
id: important_tasks
BoxLayout:
size_hint: 1, 0.08
MDRoundFlatButton:
size_hint: 1, 0.7
text: '+ Create \nlist'
line_color: 1,1,1,1
id: create_list
BoxLayout:
size_hint: 1, 0.08
MDRoundFlatButton:
size_hint: 1, 0.7
text: 'Completed \ntasks'
line_color: 1,1,1,1
id: completed_tasks
# top panel
BoxLayout:
orientation: 'vertical'
AnchorLayout:
anchor_y: 'top'
size_hint: 1, 0.05
GridLayout:
size_hint: 1, 0.05
cols: 4
rows: 1
Label:
text: 'Name'
size_hint: 0.5, 0.05
id: list_name
MDTextField:
id:search_task
halign: 'center'
valign: 'center'
hint_text: 'Search'
size_hint: 1, None
line_color_normal: 0.15,0.15,0.15
MDRectangleFlatButton:
id: rename
text: 'Rename'
line_color: 1,1,1,1
MDRectangleFlatButton:
text: 'Sort'
line_color: 1,1,1,1
id: sort
# Center
BoxLayout:
orientation: 'vertical'
size_hint: 0.1, 0.1
MDFloatingActionButton:
icon: "plus"
md_bg_color: 'black'
on_press: root.manager.current = 'adding_newTask_screen'
BoxLayout:
orientation: 'vertical'
size_hint: 1,1
BoxLayout:
ScrollView:
line_color_normal: 1,1,0,1
id: listBox
# Screen for another problem
<ImportantOrCompletedTaskCheckScreen@Screen>:
name: 'goodbye_screen'
AnchorLayout:
anchor_x: 'center'
anchor_y: 'center'
BoxLayout:
orientation: 'vertical'
size_hint: 0.5, 0.25
GridLayout:
cols: 2
rows: 1
size_hint: 0.3, 0.25
pos_hint: {'x': 0.35}
MDSwitch:
size_hint: 0.3, 0.3
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
line_color: 1, 1, 1, 1
Label:
text: 'Important'
BoxLayout:
size_hint: 0, 0.5
GridLayout:
cols: 2
rows: 1
size_hint: 0.3, 0.25
pos_hint: {'x': 0.35}
MDSwitch:
text: 'Important'
size_hint: 0.3, 0.3
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
line_color: 1, 1, 1, 1
Label:
text: 'Completed'
AnchorLayout:
anchor_x: 'center'
anchor_y: 'center'
MDRoundFlatButton:
text: 'Continue'
size_hint: 1, 0.5
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
line_color: 1, 1, 1, 1
on_press: root.manager.current='main_menu_screen'
<AddingNewTaskScreen@Screen>:
taskToTxt:taskToTxt
AnchorLayout:
anchor_x: 'center'
anchor_y: 'center'
BoxLayout:
orientation: 'vertical'
size_hint: 0.5, 0.25
MDTextField:
id: taskToTxt
hint_text: 'Name of new task'
color: 'white'
halign: 'center'
valign: 'center'
size_hint: 1, None
multiline: False
AnchorLayout:
anchor_x: 'center'
anchor_y: 'center'
MDRoundFlatButton:
text: 'Add task'
id: addTaskButton
on_press: root.addTask()
size_hint: 1, 0.5
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
line_color: 1, 1, 1, 1
Solution
In addTask you should get access to main screen
main_screen = ToDoListApp.get_running_app().root.get_screen('main_menu_screen')
and then you can add task to list
main_screen.list_view.add_widget(OneLineListItem(text=task_text, on_press=main_screen.scr))
def addTask(self):
task_text = str(self.taskToTxt.text)
sv = open('tasks.txt', 'a', encoding='utf-8')
sv.writelines(str(task_text) + '\n')
sv.close()
main_screen = ToDoListApp.get_running_app().root.get_screen('main_menu_screen')
main_screen.list_view.add_widget(OneLineListItem(text=task_text, on_press=main_screen.scr))
ToDoListApp.get_running_app().root.current = "main_menu_screen"
BTW:
ScreenManager is a parent for every Screen so you could write shorter with self.parent.
Or you could use self.manager
main_screen = self.parent.get_screen('main_menu_screen')
#main_screen = self.manager.get_screen('main_menu_screen')
# ... code ...
self.parent.current = "main_menu_screen"
#self.manager.current = "main_menu_screen"
In MainMenuScreen you could also create function to add single task
class MainMenuScreen(Screen):
def add_task(self, text):
self.list_view.add_widget(OneLineListItem(text=text, on_press=self.scr))
and then you could write it simpler in addTask
main_screen = self.parent.get_screen('main_menu_screen')
main_screen.add_task(task_text)
and in taskRead you could reduce for-loop
for text in arr:
self.add_task(text)
Answered By - furas
