self.add_widget(ViewGridLayout()) error?

[Erin Biskup]

So I'm doing some Kivy tutorials that my teacher set me, but I keep getting a syntax error on self.add_widget(ViewGridLayout()). The tutorials are all pretty much just copy and pasting the code from a word doc and figuring out by ourselves what code does what so it should be working. Here are the full .py and .kv codes:

.kv

#: import NoTransition kivy.uix.screenmanager.NoTransition

ScreenManagement:

    transition: NoTransition()

    MainScreen:

    ViewScreen:

<MainScreen>:

name: 'main'

BoxLayout:

orientation: 'vertical'

Label:

text: 'My Application'

size_hint: 1, 0.1

GridLayout:

size_hint: 1, 0.5

cols: 2

Label:

text: 'Name'

TextInput:

BoxLayout:

size_hint: 1, 0.2

Button:

text: 'Add'

Button:

text: 'Delete'

Button:

text: 'View'

on_press: app.root.current = 'view'

Label:

size_hint: 1, 0.2

text: 'Debug'

<ViewScreen>:

name: 'view'

.py

from kivy.app import App

from kivy.lang import Builder

from kivy.uix.button import Button

from kivy.uix.screenmanager import ScreenManager, Screen, NoTransition

from kivy.uix.gridlayout import GridLayout

from kivy.uix.boxlayout import BoxLayout

class MainScreen(Screen):

pass

class ViewScreen(Screen):

def btn_pressed(self, *args):

presentation.current='main'

def __init__(self, **kwargs):

super(ViewScreen, self).__init__(**kwargs)

self.add_widget(ViewBoxLayout())

class ViewBoxLayout(BoxLayout):

def btn_pressed(self, *args):

presentation.current='main'

def __init__(self, **kwargs):

super(ViewBoxLayout, self).__init__(**kwargs)

self.orientation = 'vertical'

back_btn = Button(text='Back')

back_btn.bind(on_press=self.btn_pressed)

self.add_widget(Label(text='My Application')    

self.add_widget(ViewGridLayout())              #This is where the error is occurring

self.add_widget(back_btn)

class ViewGridLayout(GridLayout):

def __init__(self, **kwargs):

super(ViewGridLayout, self).__init__(**kwargs)

self.cols = 2

class ScreenManagement(ScreenManager):

pass

class MainApp(App):

    

def build(self):

return presentation

presentation = Builder.load_file("main2.kv")

MainApp().run()

Any ideas what could be going wrong?

Thanks!

[Fari Tigar]

A bracket is missing in this line:

self.add_widget(Label(text='My Application'))

As a beginner, do yourself a favor and work with an IDE, either Pycharm or Eclipse, you would have found the error in no time.

And if you really want to impress your teacher, user kivymd, which is a library of nicer Widgets.

[Fari Tigar]

Sorry, the correct name is parentheses, you might ques that already.

[OceanArrow]

Thanks! This helped me heaps! :)

[Geekademy]

Not sure this is always the best advice to be honest. Those huge environments
have correspondingly high learning curves, even if they do help once learned.

The situation described is one of the things that every programmer must
discover, however. If you have an error and can't figure out why it is
happening, look a line or two before it. Error messages are often wrong as
well, so reading between the lines is sometimes necessary. It's something that
is a bit more obvious when learning C due to its nature (multiple compiler
errors and use of braces), but can happen in any language.

Personally I use a lightweight/fast editor that does simple bracket/paren
matching, and as I'm familiar with the rule above, do not encounter such problems.

Cheers,