Kivy Tutorial #9 - Navigation Between Multiple Screens 

Probably the first tutorial that I'm following along all the way through without quiting before it ends.. really straight forward, short videos, nice approach. Amazing man! Thanks for that. Will definitelly check your other Python videos as well. Wish you the best!

The best kivy tutorial you can find online

searched for this for a long time finally found it great video.

thank you for your representation of the kivy in python. It is really great clear and easy to understand

Thanks for the concise yet well-explained tutorials series! PS: @5:31 You just pressed Ctrl + tab, it allows you to navigate between windows

Im not native english speaker so I wrote direction with double R and spend like an hour to figure what the problem was great tutorieal

Thanks for the concise yet well-explained tutorials series! PS: @5:31 You just pressed Ctrl + tab, it allows you to navigate between windows true

Tim for the win. Thanks for the tutorial.

Hey Tim - thanks for making this series as we use kivy at school. Would you have any idea on how to transfer data between different windows (screens) in kivy?

I spent 3 hours on this because the whole time I forgot ScreenManager in the class. I was so focused on the kivy file for 3 hours that i missed that.

Could you please explain why you didn't use these pointy brackets on WindowManager but on the other two you did? I'm trying to figure out when to use what in general :)

exactly what I needed!

Taking Python to the next level ! Amazing ! Thank you !

i had learn a lot with this tutorial, thanks so much for upload it, i have been looking for something like this, now i can use python for somthing xdxd

Your information is good, i'm learning and your videos were my help... thanks

Thanks Tim, Is it possible to explain how you can pass the password value from main Screen to Second Screen ??

Exelent series of tutorials

Thank you so much, This helps with my project!!

Hey Tim, i have a problem with transitioning data between different screen.Thank you in regards.

Thanks Tim you're a legend!

Hi Tim, great video! How would you create a transition without a button? For example, hold one screen for 60 sec then auto transition to the next screen? Thanks!

thanks Tim, great work

@Tech With Tim, How do you do if you have multi pages with the same structur, but with different informations? Is it possible to have one screen in .kv and replace just the values (like text or others)?

I find a good idea for you to collaborate with the guys who made Programming hero, maybe adding a kivy topic in that app. Anyhow, nice work

Thanks to you the computer remained unharmed

How come the app.root.current can use an equal sign but everything else uses a colon. Is it because they're logic code instead of GUI code?

Great tutorial! Thanks!

I would love to see how to put the logic of password check inside python instead of inside the kivy language file, so that we can learn to keep style and logic separted

Excellent tutorial thank you

Hey Tim. Lovely video. I have a question though. Let us say we have both username and password, how do you make the condition for it to read individually?

Thanks for the tutorial! But i have a question: can i set the name of window in .py file? Not using kv language. Is it even possible to create multiple windows in .py?

You helped me alot! Thx TWT!

Hi Tim, you are much better at explaining kivy as any Course on kivy i bought on udemy. So thank you for that. The more I see from kivy the more I feel it is not that great. Many things seem overly complicated and even the logic in the code differs quite from that of python, so it is more like learning an entire new language. Also there are a lot of inconsistencies and same commands sometimes do not accept the same style, which makes it very frustrating. Sometimes you can use "=" but most of the time you have to use ":" . The documetation on it is very poor as well and it seems to give only very specific or far feched examples. Connecting it with actual python code is not intuativ at all. And the fact that you can only make an installation of that App on you phone with ubunty... What do you think about kivy? Is it actually worth learning?

how can i use both the my.kv file and a touch class we made in the previous video

Hi Tim, I noticed you only imported Builder this time, does this automatically include the GridLayout, Label, and other widgets you imported separately before?

you are amazing tim im ur fan

I'm guessing we can use a floatlayout if we wanted to??

One question how long have you been learning "Programming" and how long did it take you to become comfortable "Intermediate" Stage in a language?

hey I do the same but got black screen instead ....... what should i do?

i keep getting No screen with name "screen name" i definately have the correct screen name so what is happing?

Good stuff.

What if you want to create UI elements at runtime ? For example I want a scrollable vertical layout of buttons generated for each user input.

Oh I find what I want Label: text: "Congratulations Pro Thanks too much"

also can i use the kv file and have variables as texts of elements so i can change them

We made ScreenManager a Class. Then, how can we change transition type, transition durations etc.? Internet shows something really different.

I got this error ('NoneType' object is not subscriptable) when trying to do kv = Builder.load_file("my.kv")

why do you need to use equal signs if you use 'app.root.current = 'second' or root.manager.transition.direction = 'left'' while the rest is different??

from where did you learn kivy? Just by reading the docs? I found them very confusing, (specially considering that I have no previous experience with GUI langs or Kivy). Does anyone recommend a course?

hello, nice vid but for some challenge, do you know if there is a way to switch screen with a speech recognition on a defined key word? (I need help in fact ^^)

hi what if an app requires more than 10 pages and each having many lines of code, Like if i want to create an ecommerce app? I am able to create basic small apps but if i try to create bigger apps my codes gets dirty!

so how do you call functions from screen classes? after moving code into a screen root.functionName no longer works

first view holla tim ....how many lang do you know and were did u learned from them ...are u in university

I copied all of the code as it is until 7:17, but I get this: NameError: name 'my' is not defined(on line 18) Please help me out

you applied the logic inside the kivy design file, is there a way to apply the same logic inside the python file?

im having an attribute error that module object has no attribute load_file ? any solutions

Hi I am getting the following error when i try to switch screen by clicking and releasing submit button. " AttributeError: 'NoneType' object has no attribute 'transition'".

Hey Is there any way to switch screens from python itself??? Please Help

i wrote the same code but the Builder.load_file is giving a black screen. help!

hello, i have a problem with packing python files and kv files into one excutable file to run in windows. can you help me please ?

How to pass the values from one screen to another ex:scr1 has a text input with my name and when I click the submit button it has to move to the next screen and print the previous screen input my name

What if i want to retrive the password from sql database , can i use a variable to replace "tim" there?

thanks.

How to check value in .kv file which is returned from method in .py file?

I want to move textinput to centre of screen. How can I do this?

Does anyone how to solve this problem "[CRITICAL] [Window ] Unable to find any valuable Window provider."

Could you do a tutorial on kivymd? coz there are literally NO good tutorials on kivymd

logical statements in the kv file hmm is there a better way around, to truly seperate logic from layout?

Anyone have any idea why we do *app.root.current = "second"* and use the *=* operator? It really through me off here as we've only been using *:* in our .kv files as an *=* operator.

it isnt working for me :( it says WindowManager Class not identified :(

Hi, I was practicing this tutorial. In kv file, I gave id: pass for TextInput: and the code wasn't running. In console it said invalid syntax. Why we cannot use pass as id? is this reserved word for kv?

I don't understand it doesn't work when i try to import the file, I even copied all the part from his website and i get raise AttributeError AttributeError

Hi tim

It's Showing Keyerror:'name' as i have used same concept, just help me out.

I am using python 2.7 with kivy so when I put in the logic in the kv file like this: on_release: "second" if passw=="khiz" else "main" The submit button doesn't do anything at all. I guess because the passw.text would be returned as a unicode value. This happens a lot with python 2.7. What would be the best way to overcome this?

How can i import a Screen from another .py file?

Hello Tim, I followed your Tutorial, and it's raising attribute error... can u help me

How can ı make without .kv

If I do it this way (using the kv file to create the screens) is there a way to change screens from the python file? I've tried using WindowManager.current = "second" and ScreenManager.current = "second", but it doesn't work. Can anyone please help me?

How do I contact you?

from kivy.app import App from kivy.lang import Builder kv = Builder.load_file("my.kv") class MyApp(App): def build(self): return kv if __name__ == "__main__": MyApp.run() Hi, for the above code I am getting a error, TypeError: run() missing 1 required positional argument: 'self' can anyone help me with this ?

I keep getting an error saying "[WARNING] [Lang ] The file C:\Users\Dell\PycharmProjects\MyNEAapp\my.kv is loaded multiples times, you might have unwanted behaviours. " I have the exact code as you however I have added an extra screen. Can anyone help?

does not work for me I got File "C:\Users\jorda\anaconda3\lib\site-packages\kivy\factory.py", line 146, in __getattr__ raise FactoryException('Unknown class ' % name) FactoryException: Unknown class My code if copied off your website

It always black screen

Guys I am stuck. I follwed the videos several times and even stated over and cut and pasted code from website I am still getting the following errors: Traceback (most recent call last): File "C:/Users/jscot/Kivy Turtuial 2/main.py", line 5, in kv = Builder.load_file("my.kv") File "C:\Python\Python38\lib\site-packages\kivy\lang\builder.py", line 304, in load_file return self.load_string(data, **kwargs) File "C:\Python\Python38\lib\site-packages\kivy\lang\builder.py", line 402, in load_string widget = Factory.get(parser.root.name)(__no_builder=True) File "C:\Python\Python38\lib\site-packages\kivy\factory.py", line 145, in __getattr__ raise FactoryException('Unknown class ' % name) kivy.factory.FactoryException: Unknown class Process finished with exit code 1 Can anyone help?

will you plzz make a video on changing button sizes in kv file. not happening with me Main file code: from kivy.app import App from kivy.lang import Builder from kivy.uix.screenmanager import Screen, ScreenManager from kivy.uix.button import Button from kivy.uix.widget import Widget from kivy.lang import Builder class MainWindow(Screen): pass class SecondWindow(Screen): pass class ThirdWindow(Screen): pass class FourthWindow(Screen): pass class WindowManager(ScreenManager): pass kv = Builder.load_file("my.kv") class TestApp(App): def build(self): return kv if __name__ == "__main__": TestApp().run() test.kv file code # : # Button: # text:"See" WindowManager: MainWindow: SecondWindow: : name: "Main" GridLayout: cols:1 GridLayout: cols: 2 # Label: # text: "Password" # TextInput: # id: pa # multiline: True Button: text: "Enter New Student Details" size_hint: [4] on_release: app.root.current = "second" root.manager.transition.direction = "left" : name: "second" Button: text:"Go Back" on_release: app.root.current = "Main" root.manager.transition.direction = "right" Error: Traceback (most recent call last): File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 700, in _apply_rule setattr(widget_set, key, value) File "kivy\weakproxy.pyx", line 35, in kivy.weakproxy.WeakProxy.__setattr__ File "kivy\properties.pyx", line 497, in kivy.properties.Property.__set__ File "kivy\properties.pyx", line 1356, in kivy.properties.ReferenceListProperty.set File "kivy\properties.pyx", line 1345, in kivy.properties.ReferenceListProperty.check ValueError: Button.size_hint value length is immutable During handling of the above exception, another exception occurred: Traceback (most recent call last): File "c:/Users/adity/OneDrive/Documents/Coding/python/projects/smallgame.py", line 35, in TestApp().run() File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\app.py", line 828, in run self.load_kv(filename=self.kv_file) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\app.py", line 599, in load_kv root = Builder.load_file(rfilename) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 301, in load_file return self.load_string(data, **kwargs) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 405, in load_string rule_children=rule_children) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 657, in _apply_rule root=rctx['ids']['root'], rule_children=rule_children) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\uix\widget.py", line 469, in apply_class_lang_rules rule_children=rule_children) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 538, in apply rule_children=rule_children) File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 707, in _apply_rule e), cause=tb) kivy.lang.builder.BuilderException: Parser: File "c:\Users\adity\OneDrive\Documents\Coding\python\projects\test.kv", line 28: ... 26: Button: 27: text: "Enter New Student Details" >> 28: size_hint: [4] 29: on_release: 30: app.root.current = "second" ... ValueError: Button.size_hint value length is immutable File "C:\Users\adity\AppData\Local\Continuum\anaconda3\lib\site-packages\kivy\lang\builder.py", line 700, in _apply_rule setattr(widget_set, key, value) File "kivy\weakproxy.pyx", line 35, in kivy.weakproxy.WeakProxy.__setattr__ File "kivy\properties.pyx", line 497, in kivy.properties.Property.__set__ File "kivy\properties.pyx", line 1356, in kivy.properties.ReferenceListProperty.set File "kivy\properties.pyx", line 1345, in kivy.properties.ReferenceListProperty.check (base) C:\Users\adity\OneDrive\Documents\Coding\python\projects>

pip install PyFriday

vai zio

Ugh that logic statement reads nothing like python which is kinda annoying.

OMG... it's so dificult language . i am furtrated after this video😟😟😟

You started this video series with a question : How to create a mobile app with python? You have not answered this question by making an example app with the best functions and methods avaiable with Kivy. It was the wastage of your time and ours. Even after 10 Tutorials, I do not know how to create a mobile app with Kivy in the best way.