I want to switch screens to screen 2 from screen 1 after 3 seconds of being on screen 1.
The program compiles but it just stays on Screen1 and I want it to change to screen2 after 3 seconds of being on screen1.
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.lang import Builder
from kivy.uix.image import Image
from kivy.clock import Clock
class Screen1(Screen):
def callNext(self, dt):
self.manager.current = 'screen2'
class Screen2(Screen):
pass
kv = Builder.load_file('my.kv')
class MyApp(App):
def build(self):
return Screen1()
return kv
if __name__ == '__main__':
MyApp().run()
kv file:
#:import Clock kivy.clock.Clock
<Screen1>:
name: 'screen1'
on_enter:
Clock.schedule_once(self.callNext, 3)
canvas.before:
Rectangle:
pos: self.pos
size: self.size
source: 'logokivy.png'
<Screen2>:
name: 'screen2'
Button:
text: 'Hello'
Your code doesn't use a ScreenManager. Make the root widget a ScreenManager with the two screens as children, and it looks like everything else should be fine and it will work.
You should be able to import time and use time.sleep() to wait 3 seconds and then close it.
Related
I am writing a program that requires a label, a text_input, and a checkbox to be aligned on screen in that order. They should span the width of the screen and be at the same y level.
I have written this code in my .kv file which uses identical pos_hint values, but only the text_input box moves
Below is my .kv code:
<Union>:
BoxLayout:
orientation: "vertical"
BoxLayout:
orientation: "horizontal"
pos_hint_y: {"top":.85}
Label:
text: 'Session Length'
pos_hint: {"x":.3, "top":.85}
TextInput:
id: input
text: "test"
pos_hint: {"x":.5, "top":.85}
size_hint: 0.3, 0.05
background_disabled_normal: ""
disabled: not checkbox.active
on_text: app.return_text()
CheckBox:
id: checkbox
pos_hint: {"x":.7, "top":.85}
and here is my main.py
from kivy.core.window import Window
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.uix.dropdown import DropDown
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.gridlayout import GridLayout
from kivy.uix.screenmanager import Screen, ScreenManager
Window.size = (309, 555)
class MenuScreen(Screen):
pass
class SetupScreen(Screen):
pass
class drop_content(DropDown):
pass
class UnionScreen(Screen):
class Checkbox_Setup(FloatLayout):
pass
class TheApp(App):
def build(self):
# Create the screen manager
sm = ScreenManager()
sm.add_widget(MenuScreen(name='menu'))
sm.add_widget(SetupScreen(name='setup'))
sm.add_widget(UnionScreen(name='union'))
return sm
def return_text(self):
text = self.root.get_screen('union').ids.input.text
print(text)
def main():
Builder.load_file('menu.kv')
app = TheApp()
app.run()
if __name__ == '__main__':
main()
Finally, here is the output I am currently getting, with the label and checkbox in line but underneath the text_input which is in the right place.
I am relatively new to kivy so any help would be greatly appreciated. Thanks in advance!
I've just started my first kivy app. The app is intended to start with button "Start Scan" and then show up the QR scanner built with ZBarCam.
I'm using Screens with the ScreenManager to change from the button view to the camera view (with zbarcam), the problem is that I realized that the camera is initialized from the beginning , so before clicking on the button the camera is already on (I know it because the led from the camera is on).
I don't know if Screen should not be used in this case, or if is there a way to tell the app to do not initialize all screens.
The code I'm using is the following:
QrApp.py:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
class QrReader(Screen):
pass
class ScanButton(Screen):
pass
class QrApp(App):
pass
if __name__ == '__main__':
QrApp().run()
qrapp.kv:
ScreenManager:
id: screen_manager
ScanButton:
id: scan_btn
name: 'scan_btn'
manager: 'screen_manager'
QrReader:
id: qr_reader
name: 'qr_reader'
manager: 'screen_manager'
<ScanButton>:
BoxLayout:
orientation: 'vertical'
Button:
text:'Start Scan'
font_size:"50sp"
color: [0, 255, 255, .67]
on_press: app.root.current = 'qr_reader'
<QrReader>:
#:import ZBarCam kivy_garden.zbarcam.ZBarCam
BoxLayout:
orientation: 'vertical'
ZBarCam:
id:qrcodecam
Label:
size_hint: None, None
size: self.texture_size[0], 50
text: ' '.join([str(symbol.data) for symbol in qrcodecam.symbols])
Thanks!
==== ALTERNATIVE BASED IN A COMMENT (still fails) ====
Based on the comment from n4321d I tried to add the ZBarCam as widget in the QrReader Screen. While I can now initiate the camera when the widget is added, I don't see how I can get the symbols that is, the text read from the QR.
This alternative code is the following:
QrApp.py:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.widget import Widget
from kivy.core.window import Window
from kivy.uix.label import Label
from kivy.uix.screenmanager import ScreenManager, Screen
class QrReader(Screen):
def on_enter(self):
from kivy_garden.zbarcam import ZBarCam
zbarcam = ZBarCam()
self.add_widget(zbarcam)
self.add_widget(Label(
text='PRINT SYMBOLS', #' '.join([str(symbol.data) for symbol in zbarcam.symbols] does not work
size_hint=(None,None),
size=(Window.width*0.1, Window.height*0.1),
center=(Window.width*0.3, Window.height*0.5)))
class ScanButton(Screen):
pass
class QrApp(App):
pass
if __name__ == '__main__':
QrApp().run()
qrapp.kv
ScreenManager:
id: screen_manager
ScanButton:
id: scan_btn
name: 'scan_btn'
manager: 'screen_manager'
QrReader:
id: qr_reader
name: 'qr_reader'
manager: 'screen_manager'
<ScanButton>:
BoxLayout:
orientation: 'vertical'
Button:
text:'Start Scan'
font_size:"50sp"
color: [0, 255, 255, .67]
on_press:
app.root.current = 'qr_reader'
<QrReader>:
BoxLayout:
orientation: 'vertical'
====== SOLUTION ========
My workaround solution is posted as an answer to this question here
First:
I would also add an on_leave function where you remove your cam widget otherwise you will keep adding new widgets every time you load it.
I dont have a working cam now , so i cannot test your code. Looking at your code I think you have to bind the text in your Label to the text in zbarcam.symbols with a function: self.label = Label(....); zbarcam.bind(symbols=lambda *x: setattr(self.label, "text", str(x[1]))) or somethign like that.
Here is an example using a random text generator instead of ZBarCam (since i cannot run that).
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.widget import Widget
from kivy.core.window import Window
from kivy.uix.label import Label
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.properties import ListProperty
import random
from kivy.clock import Clock
kv_str = """
ScreenManager:
id: screen_manager
ScanButton:
id: scan_btn
name: 'scan_btn'
manager: 'screen_manager'
QrReader:
id: qr_reader
name: 'qr_reader'
manager: 'screen_manager'
<ScanButton>:
BoxLayout:
orientation: 'vertical'
Button:
text:'Start Scan'
font_size:"50sp"
color: [0, 255, 255, .67]
on_press:
app.root.current = 'qr_reader'
<QrReader>:
BoxLayout:
orientation: 'vertical'
"""
class ZBarCam(Label):
symbols = ListProperty([])
def __init__(self, **kwargs):
super().__init__(**kwargs)
Clock.schedule_interval(self.gen_rand_text, 1)
def gen_rand_text(self, *args):
self.text = random.choice(['aaaaa', 'bbbbb', 'ccccc'])
self.symbols.append(self.text)
if len(self.symbols) > 3:
del self.symbols[0]
class QrReader(Screen):
def on_enter(self):
self.zbarcam = ZBarCam()
self.add_widget(self.zbarcam)
self.label = Label(
text='PRINT SYMBOLS', #' '.join([str(symbol.data) for symbol in zbarcam.symbols] does not work
size_hint=(None,None),
size=(Window.width*0.1, Window.height*0.1),
center=(Window.width*0.3, Window.height*0.5))
self.add_widget(self.label)
self.zbarcam.bind(symbols = lambda *x: setattr(self.label, "text", str(x[1])))
def on_leave(self, *args):
self.remove_widget(self.zbarcam)
self.remove_widget(self.label)
class ScanButton(Screen):
pass
class QrApp(App):
def build(self):
return Builder.load_string(kv_str)
if __name__ == '__main__':
QrApp().run()
if it still does not work you might have to call self.zbarcam.start() too in the on_enter method after adding it
hope this helps
Thanks to answer from n4321d I finally found a solution.
I also struggled releasing the camera, as zbarcam.stop() stops zbarcam but camera was apparently still open (led was on). After digging a lot, I found this workaround which seems to work well to release the camera.
I also merged the button and qr reader in the same Class and I no longer use kv file, in this example. The final code is the following:
QrApp.py:
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.clock import Clock
from kivy_garden.zbarcam import ZBarCam
class QrScanner(BoxLayout):
def __init__(self, **kwargs):
super(QrScanner, self).__init__(**kwargs)
btn1 = Button(text='Scan Me', font_size="50sp")
btn1.bind(on_press=self.callback)
self.add_widget(btn1)
def callback(self, instance):
"""On click button, initiate zbarcam and schedule text reader"""
self.remove_widget(instance) # remove button
self.zbarcam = ZBarCam()
self.add_widget(self.zbarcam)
Clock.schedule_interval(self.read_qr_text, 1)
def read_qr_text(self, *args):
"""Check if zbarcam.symbols is filled and stop scanning in such case"""
if(len(self.zbarcam.symbols) > 0): # when something is detected
self.qr_text = self.zbarcam.symbols[0].data # text from QR
Clock.unschedule(self.read_qr_text, 1)
self.zbarcam.stop() # stop zbarcam
self.zbarcam.ids['xcamera']._camera._device.release() # release camera
class QrApp(App):
def build(self):
return QrScanner()
if __name__ == '__main__':
QrApp().run()
There is no way to lazy-load kivy Screens. Try this as a workaround: Do not let ScreenManager know about all Screens. Use switch_to to remove the current screen and load the desired one instead. Check Kivy docs to learn how to use it.
Maybe so?
from kivy_garden.zbarcam import ZBarCam
from kivymd.uix.textfield import MDTextField
class MenuScreen(MDScreen):
zbarcam: ZBarCam = ObjectProperty()
qrfield: MDTextField = ObjectProperty()
def __init__(self, **kwargs):
super().__init__(**kwargs)
self.__cam_release()
def scan(self, instance):
self.__cam_release()
def on_touch_down(self, touch):
if self.zbarcam.collide_point(*touch.pos):
self.__cam_open()
return super().on_touch_down(touch)
def __cam_release(self):
if self.zbarcam.xcamera._camera._device.isOpened():
self.zbarcam.stop()
self.zbarcam.xcamera._camera._device.release()
def __cam_open(self):
if not self.zbarcam.xcamera._camera._device.isOpened():
self.zbarcam.xcamera._camera._device.open(0)
self.zbarcam.start()
i cannot remove widget using the screen with kivy python, i dont know why it just does not do anything
the code was suppose to remove textinput with id:name on the first screen but it just does not do anything and no error message.
here is all of the code it is tested on python 3.7.4, kivy 1.11.1 on window.
module_media_player.py
import kivy
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.lang import Builder
from kivy.core.audio import SoundLoader
from kivy.uix.videoplayer import VideoPlayer
from kivy.uix.screenmanager import ScreenManager,Screen
class Player(Screen):
def press(self):
self.ids.name.text = 'nice'
def remove(self):
self.remove_widget(self.ids.name)
class MediaPlayer(Screen):
pass
class WindowManager(ScreenManager):
pass
kv = Builder.load_file('my.kv')
class GoodApp(App):
def build(self):
return kv
if __name__ == '__main__':
GoodApp().run()
my.kv
WindowManager:
Player:
MediaPlayer:
<Player>:
name:"player"
BoxLayout:
orientation:"vertical"
size:root.width,root.height
cols:2
TextInput:
id:name
multiline:False
text:"first"
font_size:12
size_hint_y:0.3
Button:
text:"click me"
on_press:root.remove()
Button:
text:"next window"
font_size:14
size_hint_y:0.7
on_release:
app.root.current = "mediaplayer"
root.manager.transition.direction = "left"
<MediaPlayer>:
name:"mediaplayer"
BoxLayout:
orientation:"vertical"
size:root.width,root.height
Label:
text:"second"
font_size:12
Button:
text:"previous window"
font_size:14
on_release:
app.root.current = "player"
root.manager.transition.direction = "right"
Your code:
def remove(self):
self.remove_widget(self.ids.name)
is trying to remove the TextInput from the Player Screen, but that Textinput is not a child of Player. It is actually a child of the BoxLayout. You can fix this by modifying your remove() method:
def remove(self):
textinput = self.ids.name
textinput.parent.remove_widget(textinput) # remove widget from its parent
I'm trying to add a digital clock to my Kivy program, it seems to be having trouble.
Here is the .py:
import kivy
kivy.require('1.10.0')
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.image import Image
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.stacklayout import StackLayout
from kivy.clock import Clock
from kivy.properties import ObjectProperty
from kivy.properties import StringProperty
import time
class IntroScreen(Screen):
pass
class ContScreen(Screen):
pass
class ScreenManagement(ScreenManager):
pass
backbone = Builder.load_file("main.kv")
class Status(FloatLayout):
_change = StringProperty()
_tnd = ObjectProperty(None)
def update(self, *args):
self.time = time.asctime()
self._change = str(self.time)
self._tnd.text = str(self.time)
print (self._change)
class XGApp(App):
time = StringProperty()
def update(self, *args):
self.time = str(time.asctime()) # + 'time'?
def build (self):
Clock.schedule_interval(self.update, 1)
return backbone
xApp = XGApp()
if __name__ == "__main__":
xApp.run()
and the .kv
<ContScreen>:
FloatLayout
size_hint: .1,.1
canvas.before:
Color:
rgba: 0,0,0,1
Rectangle:
pos: self.pos
size: self.size
Label:
text: app.time
ContScreen is the title of the screen I want to show the clock on, it's served by a separate Builder (main.kv).
Any help would be appreciated! Been struggling with this clock for a few hours now. The trouble seems to be on the .kv side from what I can tell.
BONUS: If you want to go the extra mile, I also want to add a timer that counts down x amount on press of a button on the .kv. The x amount would be different depending on which button you press.
I have made a fork of the original kivydigitalclock here. It should be easier to use than the original. You can add it to your .kv file just as any other widget. For example, something like:
<ContScreen>:
FloatLayout
size_hint: .1,.1
canvas.before:
Color:
rgba: 0,0,0,1
Rectangle:
pos: self.pos
size: self.size
Label:
text: app.time
DigitalClock:
pos_hint: {'right': 1.0, 'center_y': 0.5}
size_hint: (0.2, 0.2)
should work. Note that in your main .py file you will need to include:
from digitalclock.digitalclock import DigitalClock
(assuming that the digitalclock.py file is in a digitalclock folder)
I asked a question regarding updating label text (Kivy change label text with python) - it was answered and was working but I've been trying for hours trying to adapt my running code to ScreenManager so I can have multiple screens. I've cut down the code to the basic stuff I can't get working.
ScreenManager code breaks the solution, I know what the issue is I just can't resolve it. The code is working, text and time updating in the shell but not the labels, I couldn't add return self.first_screen to the Kivy def build so its not binding to the_time: _id_lbl_time - Any help/pointers would be really appreciated.
from kivy.app import App
from kivy.base import runTouchApp
from kivy.lang import Builder
from kivy.properties import ListProperty, StringProperty, ObjectProperty
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.screenmanager import ScreenManager, Screen, WipeTransition, FadeTransition
from kivy.uix.anchorlayout import AnchorLayout
from kivy.clock import Clock
import time
from datetime import datetime, timedelta
class FirstScreen(Screen):
def update_time(self, sec):
MyTime = time.strftime("%H:%M:%S")
print MyTime # to test update_time is called etc
self.the_time.text = MyTime #<---- self.the_time isn't working
class SecondScreen(Screen):
def update_text(self, sec):
MyText = 'New Text'
print MyText # to test update_text is called etc
self.the_set.text = MyText #<---- self.the_set isn't working
class MyScreenManager(ScreenManager):
pass
Builder.load_string('''
<FirstScreen>:
name: 'first'
the_time: _id_lbl_time
BoxLayout:
orientation: 'vertical'
Label
id: _id_lbl_time
text: 'Clock'
font_size: 30
BoxLayout:
Button:
text: 'New Here'
font_size: 20
size: 200, 50
size_hint: None, None
on_release: app.root.current = 'second'
<SecondScreen>:
name: 'second'
the_set: _id_lbl_set
BoxLayout:
orientation: 'vertical'
Label:
id: _id_lbl_set
text: 'New Here'
font_size: 30
BoxLayout:
Button:
text: 'Main'
font_size: 20
size: 200, 50
size_hint: None, None
on_release: app.root.current = 'first'
''')
class ScreenManagerApp(App):
def build(self):
sm = ScreenManager()
sm.add_widget(FirstScreen(name='first'))
sm.add_widget(SecondScreen(name='second'))
self.first_screen = FirstScreen()
self.sec_screen = SecondScreen()
return sm #<---- I can't return self.first_screen etc here?
def on_start(self):
Clock.schedule_interval(self.first_screen.update_time, 1) # 1 second
Clock.schedule_interval(self.sec_screen.update_text, 2)
ScreenManagerApp().run()
I can't return self.first_screen etc here?
No. There has to be a ScreenManager on top of the Screen widgets, otherwise it's just a RelativeLayout as is its definition in the source code.
You experienced a really common mistake by beginners. You used one instance FirstScreen() and SecondScreen() for ScreenManager(those are visible) and then you created another instances with:
self.first_screen = FirstScreen()
self.sec_screen = SecondScreen()
which you then used for Clock:
Clock.schedule_interval(self.first_screen.update_time, 1)
Clock.schedule_interval(self.sec_screen.update_text, 2)
and that means text properties in instances that actually aren't added anywhere as widgets were used for updating. The instances exist, so no error to trigger except the visual one → you don't see the values, because you used wrong instance.
Correct build():
def build(self):
sm = ScreenManager()
self.first_screen = FirstScreen(name='first')
self.sec_screen = SecondScreen(name='second')
sm.add_widget(self.first_screen)
sm.add_widget(self.sec_screen)
return sm