toolbar from kivymd haven't left_action_items

Question

How determine in toolbar from kivymd left_action_items or right_action_items on pure python.

i try write :left_action_items: [['icon.png', lambda x: pass]]

 from kivymd.theming import ThemeManager
 from kivy.uix.boxlayout import BoxLayout
 from kivy.app import App
 from kivymd.toolbar import Toolbar
 class StartScreen(BoxLayout):
    def __init__(self, **args):
        super().__init__(**args)
        self.orientation = 'vertical'
        toolbar = Toolbar(title = 'Welcome', left_action_items = [['red.png', lambda x: print('hello')]]) 
        self.add_widget(toolbar)

 class Program(App): 
    theme_cls = ThemeManager()
    title = "Application"
    def build(self): 
        return StartScreen()    

Program().run() 

write error: KeyError = 'left_action'

Answer 1

You can try to add the left_action_items property after instantiating the Toolbar widget.

toolbar = Toolbar(title = "Welcome")
toolbar.left_action_items = [["facebook", lambda x: print('Hello World')]]

You can find some icons from kivymd at icon_definitions.py.