I'm learning how to use kivy. And to get things a little more difficult, I'm using kivyMD to use themes.
I'm trying to simply create a layout in a kivy file and fill it with a python loop in the python file.
My python file, for example :
from kivy.lang import Builder
from kivymd.app import MDApp
from kivymd.uix.label import MDLabel
from kivymd.uix.screen import MDScreen
KV="""
MyWidget:
MDBoxLayout:
orientation: 'vertical'
MDLabel:
text:"hello world !"
halign: 'center'
MDGridLayout:
id: _grid
col: 2
MDLabel:
text:"hello world !"
halign: 'center'
"""
class MyWidget(MDScreen):
def on_grid(self):
for i in range(6):
self.ids._grid.add_widget(MDLabel(text=str(i+1)))
pass
#Déclaration du moteur d'application
class MainApp(MDApp):
def build(self):
return Builder.load_string(KV)
if __name__=='__main__':
MainApp().run()
But the GridLayout stays empty.
I really search and tried other solutions with ObjectProperty() but I got even more errors. And I was unable to find a simple example, something less specific and more academic.
What is the best way to create an empty nested widget in a kv file and then fill it with a python loop at launch ?
Thank you for your help.
After a lot of researchs, I found a solution. I hope it will help someone.
'''
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.properties import ObjectProperty
from kivy.lang import Builder
KV="""
<MainScreen>:
grid: _grid
BoxLayout:
Label:
text: "Hello 1 !"
GridLayout:
id: _grid
cols:2
Label:
text: "Hello 2 !"
"""
Builder.load_string(KV)
class MainScreen(Screen):
grid = ObjectProperty()
def __init__(self, **kwargs):
super(MainScreen, self).__init__(**kwargs)
for i in range(6):
self.grid.add_widget(Label(text=str(i)))
class MyApp(App):
def build(self):
return MainScreen()
if __name__ == '__main__':
MyApp().run()
Related
I am able to get the data in main app class and run it to get as Label but when I want to do the same by getting data in main app class where as defining Label in another class, it's giving name error.
import kivy
from kivy.app import App # import Kivy App module to create
from kivy.uix.label import Label # import Label Module
kivy.require('1.11.1')
class MyKivyApp(App):
def build(self):
f=open('tesit.txt','r')
t=f.read()
return Label(text =t)
rt=MyKivyApp()
rt.run()
Your lines:
rt=MyKivyApp()
rt.run()
are inside the MyKivyApp. Just unindent those two lines to get them outside of the App class.
This's how we can read a text file and display it as label in another screen in kivy.
from kivy.app import App
from kivy.uix.screenmanager import Screen
from kivy.lang import Builder
from kivy.properties import StringProperty
class Screen1(Screen):
f=open('test.txt','r')
t=f.readlines()
b=t[0]
f.close()
class Screen2(Screen):
username = StringProperty("")
root = Builder.load_string('''
<Screen1>:
name:'xy'
id:loginscreen
BoxLayout:
orientation: "vertical"
Button:
text:'Execution button'
on_release: root.manager.current = "screen2"
<Screen2>:
name: "screen2"
FloatLayout:
Label:
text: root.username
Button:
text:'Back to menu'
size_hint:.3,.3
on_release: root.manager.current = "xy"
ScreenManager:
Screen1:
id:loginscreen
Screen2:
username: loginscreen.b
''')
class MyApp(App):
def build(self):
return root
r=MyApp()
r.run()
I want to be able to scroll within the buttons numbered 10-1 but it wont let me scroll. Any solutions? I was finally able to put the buttons in a scrollview but after all my effort I am not able to move it. It just crams into the space provided and doesn't move at all.
orientation: "vertical"
SongText:
size_hint: 1,0.35
PausePlay:
size_hint: 1,0.1
ScrollView:
orientation: "vertical"
PlayList:
orientation: "vertical"
AddDeleteShuffle:
size_hint: 1,0.2
<SongText>:
Label:
id: songtitle
text: "Song Title"
<PausePlay>:
Button:
id: play
text: "Play"
Button:
id: pause
text: "Pause"
This is the main area of focus I think nothing is needed here but who knows.
<PlayList>: #Main area of conceren
<AddDeleteShuffle>:
BoxLayout:
Button:
text: "Shuffle"
Button:
text: "Delete"
Button:
text: "Shuffle"
kv file ^
py file
import kivy
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.uix.anchorlayout import AnchorLayout
from kivy.uix.scrollview import ScrollView
from kivy.uix.stacklayout import StackLayout
from kivy.uix.gridlayout import GridLayout
from kivy.metrics import dp
from kivy.core.audio import SoundLoader
from kivy.properties import ObjectProperty, StringProperty
from kivy.uix.screenmanager import ScreenManager, Screen
class AddDeleteShuffle(BoxLayout):
pass
class PlayList(BoxLayout):
def __init__(self,**kwargs):
super().__init__(**kwargs)
for i in range(0,10):
size = dp(100)
b = Button(text=str(i+1), size_hint=(1,None), size=(size,size))
self.add_widget(b)
Class for the playlist it is inside a scroll view, but I can't move it. Maybe I have to add a layout in the kv file. I have no idea.
class PausePlay(BoxLayout):
pass
class SongText(BoxLayout):
pass
class AppLayout(BoxLayout):
pass
class Sound5App(App):
def build(self):
return AppLayout()
if __name__ == "__main__":
Sound5App().run()
i want to make nested for loop in kivy language by using on_perent then i try the slashes but there is error invalid indentation must be a multiple of 4 spaces i don't know what to do and there is no other than slashes
from kivy.app import App
from kivy.lang import Builder
kv = Builder.load_string('''
#:import Button kivy.uix.button.Button
BoxLayout:
BoxLayout:
on_parent:for i in range(2):\n \t \b\b\b\b\b \
on_parent:for i in range(3):\n \t \
on_parent:self.add_widget(Button(text=str(i)))
''')
class TestApp(App):
def build(self):
return kv
TestApp().run()
This is a way of doing the nested for loop but I don't understand what you are trying to achieve
from kivy.app import App
from kivy.lang import Builder
kv = Builder.load_string('''
#:import Button kivy.uix.button.Button
BoxLayout:
BoxLayout:
on_parent:
if not self.children: [self.add_widget(Button(text=str(j))) for i in range(2) for j in range(3)]
''')
class TestApp(App):
def build(self):
return kv
TestApp().run()
How do I change the button's color when it's down? As in, when you press the button, replace the blue-ish colour into another one?
I've tried fiddling around with background_color_down, background_color_normal, I tried using canvas and the sort but nothing seems to have the effect I intend it to
Or you could try giving the path to a png file with your design of the pressed button to the background_down attribute. Here my file is called "pressed.png" and is located within the same folder as the python programm. this is a link to something i made within 30 seconds in inkscape.
#!/usr/bin/python3.5
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.lang.builder import Builder
from kivy.properties import ObjectProperty, ListProperty
from kivy.atlas import Atlas
kv= Builder.load_string('''
<MainScreen>
my_but:my_but
orientation: "vertical"
size_hint:1,1
# size_hint: 0.3,0.3
# pos_hint:{"center_x": 1, "center_y":1}
Label:
size_hint: 0.5,0.4
text: "Look at my Button go:"
Button:
id:my_but
size_hint: 0.5,0.4
text: "klick me"
# background_normal: ""
background_down: "pressed.png"
''')
class MainScreen(BoxLayout):
my_but = ObjectProperty(None)
def __init__(self, **kwargs):
super(MainScreen, self).__init__(**kwargs)
class myApp(App):
def build(self):
return MainScreen()
if __name__ == "__main__":
myApp().run()
Simple problem I'm having:
When I click a button in my Kivy/Python app, I want to gain access to the ID of that button.
# Kivy code
Button:
id: position_1
on_press: app.access_button_id()
I have had various trial and error attempts but I cannot figure it out. The button is nested as follows (as part of a bigger app), if this is a factor in my problem:
FloatLayout:
AnchorLayout:
ScreenManager:
Screen:
BoxLayout:
FloatLayout:
Button:
id: position_1
on_press: app.access_button_id()
Here is my Python code, which returns all of the id's. That's as close as I have got:
# Python code
def access_button_id(name):
print(self.root.ids)
The problem I've got is that I don't even know what I should be looking at in the documentation as I do not fully understand the terminology yet, so I can't find the right information to learn from.
EDIT:
The (name) passed into the function is for some other functionality, not related to this problem.
You already know the id - you set it yourself. These are mostly used as a hard-coded values in your code:
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.lang import Builder
Builder.load_string('''
<MyWidget>:
Button:
id: id_value_1
text: 'Print my id'
on_press: print({'id_value_1': self.proxy_ref})
Button:
id: id_value_2
text: 'Print all ids'
on_press: print(root.ids)
''')
class MyWidget(BoxLayout):
pass
class MyApp(App):
def build(self):
widget = MyWidget()
print({'id_value_1': widget.ids['id_value_1']})
return widget
if __name__ == '__main__':
MyApp().run()
Why do you need id of a Button if you already have an access to it? What are you trying to accomplish?
EDIT
An example solution to problem mentioned in the comment:
import random
import functools
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.popup import Popup
from kivy.uix.button import Button
from kivy.lang import Builder
Builder.load_string('''
<MyWidget>:
Button:
text: 'B1'
on_press: root.open_popup(self)
Button:
text: 'B2'
on_press: root.open_popup(self)
''')
class MyWidget(BoxLayout):
def open_popup(self, caller):
fun = functools.partial(self.rename, caller)
popup = Popup(
title='Test popup',
content=Button(
text='rename',
on_press=fun
),
size_hint=(None, None), size=(400, 400)
)
popup.open()
def rename(self, caller, *args):
caller.text = ''.join(chr(random.randint(48, 90)) for i in range(5))
class MyApp(App):
def build(self):
return MyWidget()
if __name__ == '__main__':
MyApp().run()