add documentation

website/documentation/content/timer_documentation.py

@@ -32,4 +32,32 @@ def handle_click():
     ui.button('Notify after 1 second', on_click=handle_click)
 
 
+@doc.demo("Don't start immediately", '''
+    By default, the timer will start immediately.
+    You can change this behavior by setting the `immediate` parameter to `False`.
+    This will delay the first execution of the callback by the given interval.
+''')
+def start_immediately_demo():
+    from datetime import datetime
+
+    label = ui.label()
+    ui.timer(1.0, lambda: label.set_text(f'{datetime.now():%X}'), immediate=False)
+
+
+@doc.demo('Global app timer', '''
+    While `ui.timer` is kind of a UI element that runs in the context of the current page,
+    you can also use the global `app.timer` for UI-independent timers.
+''')
+def app_timer_demo():
+    from nicegui import app
+
+    counter = {'value': 0}
+    app.timer(1.0, lambda: counter.update(value=counter['value'] + 1))
+
+    # @ui.page('/')
+    def page():
+        ui.label().bind_text_from(counter, 'value', lambda value: f'Count: {value}')
+    page()  # HIDE
+
+
 doc.reference(ui.timer)