added dialog classmethod

test_dialog.py

@@ -0,0 +1,21 @@
+from nicegui import ui
+import asyncio
+
+async def test_dialog():
+    # Create dialog
+    dialog = ui.dialog()
+    with dialog:
+        ui.label('Test Dialog')
+        with ui.row():
+            ui.button('OK', on_click=lambda: dialog.submit('ok'))
+            ui.button('Cancel', on_click=lambda: dialog.submit('cancel'))
+    
+    # Open and await result
+    result = await dialog
+    print(f"Dialog result: {result}")
+    return result
+
+# Test if we can check the signature
+import inspect
+print(inspect.signature(ui.dialog.__init__))
+print(inspect.signature(ui.dialog.submit))