(Kivy) How do I display new content on my canvas in Kivy? - python

This should be a pretty easy fix. I'm new to Kivy. I'm trying to have the canvas cleared on a button press, and then display a new widget to essentially move to another page. When I run it and press the button, the canvas is cleared, but I get nothing from IntroPage.
Python Script:
import kivy
kivy.require('2.0.0')
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.gridlayout import GridLayout
from kivy.uix.button import Button
from kivy.uix.image import Image
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
class ABT(App):
def build(self):
return WelcomePage()
class WelcomePage(Widget):
def btn(self):
self.canvas.clear()
print('pressed')
return IntroPage()
class IntroPage(Widget):
def __init__(self):
pass
if __name__ == '__main__':
ABT().run()
KV File:
<WelcomePage>
canvas.before:
Color:
rgba: (.43,.51,.92,.26)
Rectangle:
pos: self.pos
size: self.size
GridLayout:
cols:1
size: root.width, root.height
Image:
source: 'abt1t.png'
size_hint: (1,.8)
Button:
text:"begin"
background_color: (.43,.51,.92,.26)
size_hint: (1,.2)
on_press: root.btn()
<IntroPage>
GridLayout:
cols:1
Label:
text:"This won't show up!"

Returning IntroPage from btn won't work, as btn isn't a build method.
The best way to implement multiple pages is probably to use ScreenManager:
from kivy.uix.screenmanager import ScreenManager, Screen
class ABT(App):
def build(self):
sm = ScreenManager()
sm.add_widget(WelcomePage(name="welcome"))
sm.add_widget(IntroPage(name="intro"))
return sm
class WelcomePage(Screen):
def btn(self):
print('pressed')
self.manager.current = "intro"
class IntroPage(Screen):
def __init__(self):
pass

Related

Kivy: Navigation bar on all screens

I want to keep the Navigationbar on all my screen, I am able to switch screen and display what I want but I don't seem to keep the Navigationbar.
Also for some reason my side menu seems to appear twice, overlapping each other and I'm not sure why, I've tried refactoring the code and it just seems to appear again
Can anyone offer any help?
*.py
import kivy
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.properties import StringProperty
from kivy.uix.label import Label
from kivy.uix.gridlayout import GridLayout
from kivy.uix.scrollview import ScrollView
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.anchorlayout import AnchorLayout
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.clock import Clock
from kivy.uix.button import Button
from kivy.core.window import Window
from kivymd.app import MDApp
from kivymd.uix.card import MDCard
from kivymd.uix.label import MDLabel
class FirstWindow(Screen):
pass
class ThirdWindow(Screen):
def on_pre_enter(self):
anchor = AnchorLayout(size=(1,1))
test = "This is the new window"
card = MDCard(orientation='vertical',padding="8dp",size_hint=(1,0.5),pos_hint={'top': 0.1,'right':1},radius=[5, ])
card.test = test
card.add_widget(MDLabel(text=test, halign="center"))
anchor.add_widget(card)
self.anchorID.add_widget(anchor)
class WindowManager(ScreenManager):
pass
class NearMeApp(MDApp):
def build(self):
self.theme_cls.theme_style ="Dark"
self.theme_cls.accent_palette = "Red"
self.theme_cls.primary_palette = "Purple"
self.root = Builder.load_file('NearMe.kv')
if __name__ == '__main__':
NearMeApp().run()
*.kv
#:import hex kivy.utils.get_color_from_hex
#:kivy 1.10.1
WindowManager:
FirstWindow:
ThirdWindow:
<FirstWindow>:
name:"FirstWindow"
Screen:
MDNavigationLayout:
ScreenManager:
Screen:
BoxLayout:
orientation: 'vertical'
MDToolbar:
title: "NearMe Application"
elevation: 10
left_action_items: [['menu', lambda x: nav_drawer.set_state("open")]]
Widget:
MDNavigationDrawer:
id: nav_drawer
BoxLayout:
orientation:'vertical'
Button:
text:"ThirdWindow"
on_release: root.manager.current = "ThirdWindow"
<ThirdWindow>:
name:"ThirdWindow"
anchorID:anchorID
AnchorLayout:
id:anchorID
canvas.before:
Color:
rgba: .2, .2, .2, 1
Rectangle:
pos: self.pos
size: self.size
Your md toolbar needs to be above the main windowmanager.
With your mdtoolbar as a child of firstwindow (child of windowmanager), your windowmanager acts on it and the other children of firstwindow at same during change in current window. By moving the mdtoolbar out of firstwindow and above windowmanager the mdtoolbar will remain present.
from kivymd.app import MDApp
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager
from kivy.uix.screenmanager import Screen
class FirstWindow(Screen):
pass
class ThirdWindow(Screen):
pass
class WindowManager(ScreenManager):
pass
kv = """
Screen:
MDNavigationDrawer:
id: nav_drawer
BoxLayout:
orientation:'vertical'
Button:
text:"ThirdWindow"
on_release: root.ids.manager.current = "ThirdWindow"
StackLayout:
MDToolbar:
title: "NearMe Application"
size_hint: (1, 0.1)
elevation: 10
left_action_items: [['menu', lambda x: nav_drawer.set_state("open")]]
WindowManager:
id: manager
FirstWindow:
ThirdWindow:
<FirstWindow>:
name:"FirstWindow"
Screen:
BoxLayout:
orientation: 'vertical'
Widget:
<ThirdWindow>:
name:"ThirdWindow"
anchorID:anchorID
AnchorLayout:
id:anchorID
canvas.before:
Color:
rgba: .2, .2, .2, 1
Rectangle:
pos: self.pos
size: self.size
"""
class Test(MDApp):
def __init__(self, **kwargs):
super().__init__(**kwargs)
self.screen = Builder.load_string(kv)
def build(self):
return self.screen
the_app = Test()
the_app.run()
The above removes the toolbar from your FirstWindow and places it on its own. In your example the toolbar is a child of FirstWindow so when you change the current window (screen) to ThirdWindow the toolbar disappears with its parent (FirstWindow). Now the toolbar is not a child of either window.

kivy - how to prepare app for touch events

I am developing an app using Kivy for Android and IOS, i haven't tried it on any mobile yet but i have been noticing that i need to add some sort off 'touch' events so the buttons, swipes and etc will work on a mobile touchscreen.
i've tried searching around for examples but i didn't exactly get the concept, and i was wondering what exactly do i need to do for it to be ready for touch events, i am thinking of making a 'swiping touch' to move between pages on both sides, what do i need to do to make this happen?
When you want to swipe through pages as you have mentioned. It could be a nice option to use PageLayout. Check the docs:https://kivy.org/doc/stable/api-kivy.uix.pagelayout.html
PageLayout is where you have several pages and you can swipe through them. It could be suitable for you.
Here is a very simple example.Where you will have three pages
PageLayout:
Button:
text: 'page1'
Button:
text: 'page2'
Button:
text: 'page3'
Here is a advanced pagelayout example from kv file. The pagelyout then consists of floatlayouts. But you could use other layouts too
<Example>:
PageLayout:
FloatLayout:
id: string1
canvas:
Color:
rgb:utils.get_color_from_hex("#2BFFFA")
Rectangle:
size: self.size
pos:self.pos
Image:
size_hint:.9,1
pos_hint:{"top": 1,"right": 1}
source: "string/str1.png"
FloatLayout:
canvas:
Color:
rgb:utils.get_color_from_hex("#39FF22")
Rectangle:
size: self.size
pos:self.pos
Image:
size_hint:.9,1
pos_hint:{"top": 1,"right": 1}
source: "string/str1_sol.png"
FloatLayout:
canvas:
Color:
rgb:utils.get_color_from_hex("#2BFFFA")
Rectangle:
size: self.size
pos:self.pos
Image:
size_hint:.9,1
pos_hint:{"top": 1,"right": 1}
source: "string/str2.png"
Notice that my main layout is a pagelayout and in the floatlayout I have floatlayouts. So now I have three pages to swipe through
Or you could use a screemanger to manage your screens. . And then you just have to click on a button and then you will automatically switch screens. Here is a example. This is better than pagelayouts.
import kivy
from kivy.app import App
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.properties import ObjectProperty
class ScreenOne(Screen):
def __init__ (self,**kwargs):
super (ScreenOne, self).__init__(**kwargs)
my_box1 = BoxLayout(orientation='vertical')
my_label1 = Label(text="BlaBlaBla on screen 1", font_size='24dp')
my_button1 = Button(text="Go to screen 2",size_hint_y=None, size_y=100)
my_button1.bind(on_press=self.changer)
my_box1.add_widget(my_label1)
my_box1.add_widget(my_button1)
self.add_widget(my_box1)
def changer(self,*args):
self.manager.current = 'screen2'
class ScreenTwo(Screen):
def __init__(self,**kwargs):
super (ScreenTwo,self).__init__(**kwargs)
my_box1 = BoxLayout(orientation='vertical')
my_label1 = Label(text="BlaBlaBla on screen 2",font_size='24dp')
my_button1 = Button(text="Go to screen 1",size_hint_y=None, size_y=100)
my_button1.bind(on_press=self.changer)
my_box1.add_widget(my_label1)
my_box1.add_widget(my_button1)
self.add_widget(my_box1)
def changer(self,*args):
self.manager.current = 'screen1'
class TestApp(App):
def build(self):
my_screenmanager = ScreenManager()
screen1 = ScreenOne(name='screen1')
screen2 = ScreenTwo(name='screen2')
my_screenmanager.add_widget(screen1)
my_screenmanager.add_widget(screen2)
return my_screenmanager
if __name__ == '__main__':
TestApp().run()

Kivy content sizes adjustment

I have been started to work in kivy recently. The thing what I am doing now is, i have a blank page with a button, when I click that button it navigates to an user input screen. It works fine, but the content comes in a very small input boxes and text as in the picture.
My question is that I want it bigger and centred.
Here is my code:
In python:
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.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.uix.widget import Widget
from kivy.lang import Builder
class LoginScreen(GridLayout):
def __init__(self, **kwargs):
super(LoginScreen, self).__init__(**kwargs)
self.cols = 2
self.add_widget(Label(text="Username:"))
self.username = TextInput(multiline=False)
self.add_widget(self.username)
self.add_widget(Label(text="Password:"))
self.password = TextInput(multiline=False, password=True)
self.add_widget(self.password)
self.add_widget(Label(text="Two Factor Auth:"))
self.tfa = TextInput(multiline=False)
self.add_widget(self.tfa)
class MainScreen(Screen):
pass
class AnotherScreen(Screen):
pass
class ScreenManagement(ScreenManager):
pass
presentation = Builder.load_file("screen.kv")
class SimpleKivy(App):
def build(self):
return presentation
if __name__ == "__main__":
SimpleKivy().run()
In kv:
#: import FadeTransition kivy.uix.screenmanager.FadeTransition
ScreenManagement:
transition: FadeTransition()
MainScreen:
AnotherScreen:
<MainScreen>:
name: "main"
Button:
color: 0,1,0,1
font_size: 25
size_hint: 0.3,0.2
text: "Click"
on_release: app.root.current = "other"
pos_hint: {"right":1, "top":1}
<AnotherScreen>:
name: "other"
GridLayout:
LoginScreen
In your screen.kv, you have the LoginScreen inside a GridLayout. Since the LoginSCreen is a GridLayout, you do not need that extra GridLayout.
Just change:
<AnotherScreen>:
name: "other"
GridLayout:
LoginScreen
to:
<AnotherScreen>:
name: "other"
LoginScreen:

Scrollview to display different videos in kivy lags after a while

I'm a beginner in kivy and python. I've been trying to create a scrollview in a page that displays selected video on the screen. But after a while when i selected 5-6 videos to display even though i delete the video widget it starts to lag. And i'm open to any suggestions to better way to handle this kind of application.
from kivy.config import Config
Config.set('graphics', 'width', '1920')
Config.set('graphics', 'height', '1080')
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.uix.widget import Widget
from kivy.uix.image import Image
from kivy.properties import StringProperty
from kivy.uix.scrollview import ScrollView
from kivy.uix.label import Label
from kivy.clock import Clock
from kivy.uix.button import Button
import os
from kivy.uix.video import Video
from kivy.uix.videoplayer import VideoPlayer
from kivy.clock import mainthread
from functools import partial
from kivy.core.window import Window
Window.clearcolor = (0, 0, 0, 0)
isThereVideo=False
picture_path="/home/linux/kivyFiles/kivyLogin/assets"
video_path="/home/linux/kivyFiles/kivyLogin/videoAssets/"
class Image(Image):
pass
class MainScreen(Screen):
pass
class AnotherScreen(Screen):
pass
class Selfie(Screen):
pass
class RootWidget(Widget):
def __init__(self, **kwargs):
super(RootWidget, self).__init__(**kwargs)
Clock.schedule_once(self.createMultipleButton)
#mainthread
def createMultipleButton(self, dt):
self.root = Widget()
size_y=150;
size_x=150;
for i in range(1):
folderList = os.listdir(picture_path)
if len(folderList)==0:
time.sleep(1)
break
fileList = os.listdir(picture_path)
print fileList
for file in fileList:
x = (picture_path+"/"+file)
button = Button(id=str(file),text="" + str(file),size_hint=(None, None),height=size_y,width=size_x, pos_hint={'x': 0, 'y': 1},background_normal=x)
button.bind(on_release=partial(self.VideoContainer, file))
print file
self.scrollview.content_layout.add_widget(button)
print button.id
print("Parent of ScreenTwo: {}".format(self.parent))
#print(button.pos)
def VideoContainer(self,name,btn):
global isThereVideo
if isThereVideo==True:
#self.videocontainer.video_layout.unload()
self.videocontainer.clear_widgets()
mylist=name.split('.')
emailButton = Button(id='email')
video = Video(source="/home/linux/kivyFiles/kivyLogin/videoAssets/"+mylist[0]+".mp4", state='play',options={'eos': 'loop'})
video.size=(self.parent.width,self.parent.height)
video_pos=(self.parent.x,self.parent.y)
#video.pos_hint={'x': self.parent.width /2, 'y': self.parent.height/2}
video.play=True
#video.pos=(self.parent.width /2 , self.parent.height/2)
#self.videocontainer.video_layout.add_widget(emailButton)
self.videocontainer.add_widget(emailButton)
emailButton.add_widget(video)
isThereVideo=True
print("Parent of ScreenTwo: {}".format(self.parent))
return 0
class ScreenManagement(ScreenManager):
pass
class VideoContain(Widget):
pass
class ScrollableContainer(ScrollView):
pass
presentation = Builder.load_file("login.kv")
class MainApp(App):
def build(self):
return presentation
if __name__ == '__main__':
Window.fullscreen = True
app=MainApp()
app.run()
And my Kv file
ScreenManagement:
MainScreen:
Selfie:
<MainScreen>:
name: 'main'
Button:
on_release: app.root.current = 'selfie'
text: 'Another Screen'
font_size: 50
<Selfie>:
name: 'selfie'
Button:
on_release: app.root.current = 'login'
text: 'Selfie Screen'
font_size: 10
pos_hint: {"right": 1, 'top':1}
size_hint: (0.1, 0.1)
RootWidget:
<RootWidget>
size_hint: (0.1, None)
scrollview: scrollview
videocontainer:videocontainer
size:(self.parent.width, self.parent.height)
VideoContain:
id:videocontainer
##size:(self.parent.width, self.parent.height)
size:(root.width, root.height)
ScrollableContainer:
id: scrollview
size: root.size
pos: root.pos
<VideoContain>
video_layout:video_layout
FloatLayout:
cols:1
id: video_layout
<ScrollableContainer>:
scroll_timeout: 75
scroll_distance: 10
app: app
content_layout: content_layout
GridLayout:
id: content_layout
cols: 1
size_hint: (0.1, None)
pos: root.pos
height: self.minimum_height
padding: 25
spacing: 25
I posted all my code since i don't know which part may causing the problem i'm facing.
Solved it.
def VideoContainer(self,name,btn):
global isThereVideo
if isThereVideo:
# self.videocontainer.video_layout.unload()
self.videocontainer.clear_widgets()
In this part i'm clearing the widgets but i also need to unload the video somehow.
self.video.unload() solved my problem

Changing kivy widget properties within Class

I'm having difficulty figuring out how to change the text of a label within a kivy widget. For simplicity, I have a label set to 0 and I would like to change the text to read 30 in this example. However, I get the following error.
AttributeError: 'super' object has no attribute 'getattr'
I understand that I'm probably not properly targeting that widget and I am hoping someone can please explain how to specifically reference the text of this label (self.ids.mainel1temp.stuff_r.text = '30') to update (with more detail than fixing the code)
#!/usr/bin/kivy
import kivy
from random import random
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.gridlayout import GridLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.uix.switch import Switch
from kivy.uix.label import Label
from kivy.config import Config
Config.set('graphics', 'width', '800')
Config.set('graphics', 'height', '480')
Builder.load_string("""
<Menuscreen>:
#Handling the gesture event.
ScreenManager:
id: manager
Screen:
id: main_screen
name:'main_screen'
stuff_r: mainel1temp
FloatLayout:
Label:
id: mainel1temp
size: self.texture_size
text:'0'
size_hint: None, None
text_size: 75,75
pos: 295,308
font_size:'20sp'
halign: 'center'
""")
class Thermostuff(Screen):
stuff_r = ObjectProperty(None)
def starttherm(self):
Clock.schedule_interval((self.read_temp), 1)
def read_temp(self, dt):
self.ids.mainel1temp.stuff_r.text = '30'
Thermrun = Thermostuff()
Thermrun.starttherm()
class MenuScreen(Screen):
pass
sm = ScreenManager()
menu_screen = MenuScreen(name='menu')
sm.add_widget(menu_screen)
class TestApp(App):
def build(self):
return sm
if __name__ == '__main__':
TestApp().run()
You do a couple of things wrong here.
You dont want to put a ScreenManager inside a Screen
Only one ScreenManager is needed.
Then you can start the Clock in the __init__ of the Thermostuff(Screen)
Or if you want it to initiate on_enter you need to overrite that. In that case you might want to check somehow, if its allready started, so you wont have multiple clocks running.
Then when you create an ObjectProperty you dont need self.ids, because you allready created that property. So self.stuff_r is now the label.
I rewrote your example a bit, to demonstrate this.
Try this:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen
from kivy.properties import ObjectProperty
from kivy.clock import Clock
sm = """
#Handling the gesture event.
ScreenManager:
id: manager
MenuScreen:
Button:
text: "Go to Thermostuff"
on_release:
root.current = "main_screen"
Thermostuff:
name:'main_screen'
stuff_r: mainel1temp
FloatLayout:
Label:
id: mainel1temp
size: self.texture_size
text:'0'
size_hint: None, None
text_size: 75,75
pos: 295,308
font_size:'20sp'
halign: 'center'
"""
class Thermostuff(Screen):
stuff_r = ObjectProperty(None)
test_temp = 0
def __init__(self,**kwargs):
super(Thermostuff,self).__init__(**kwargs)
Clock.schedule_interval((self.read_temp), 1)
def read_temp(self, dt):
self.test_temp += 1
self.stuff_r.text = str(self.test_temp)
class MenuScreen(Screen):
pass
class TestApp(App):
def build(self):
return Builder.load_string(sm)
if __name__ == '__main__':
TestApp().run()

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