add documentation

website/documentation.py

@@ -167,6 +167,7 @@ def create_full() -> None:
     load_demo(ui.expansion)
     load_demo(ui.splitter)
     load_demo('tabs')
+    load_demo(ui.stepper)
     load_demo(ui.menu)
 
     @text_demo('Tooltips', '''

website/more_documentation/stepper_documentation.py

@@ -0,0 +1,19 @@
+from nicegui import ui
+
+
+def main_demo() -> None:
+    with ui.stepper(value='Preheat').props('vertical').classes('w-full') as stepper:
+        with ui.step('Preheat'):
+            ui.label('Preheat the oven to 350 degrees')
+            with ui.stepper_navigation():
+                ui.button('Next', on_click=stepper.next)
+        with ui.step('Ingredients'):
+            ui.label('Mix the ingredients')
+            with ui.stepper_navigation():
+                ui.button('Next', on_click=stepper.next)
+                ui.button('Back', on_click=stepper.previous).props('flat')
+        with ui.step('Bake'):
+            ui.label('Bake for 20 minutes')
+            with ui.stepper_navigation():
+                ui.button('Done', on_click=lambda: ui.notify('Yay!', type='positive'))
+                ui.button('Back', on_click=stepper.previous).props('flat')