added dialog classmethod

src/niceguiex/async_elements/base.py

@@ -34,6 +34,47 @@ class AsyncElement(ABC, Generic[T]):
 
         return instance._element  # Return the NiceGUI element with proper typing
 
+    @classmethod
+    async def as_dialog(cls, element_type: Type[T] = ui.column, *args, **kwargs) -> Any:
+        """Create element inside a dialog and await its result
+
+        Works like create() but wraps the element in a dialog with a card that opens automatically
+        and returns the dialog result when submitted.
+
+        The dialog can be submitted using dialog.submit(result) from within the build() method.
+        Access the dialog via self._dialog in your build() implementation.
+
+        Returns the value passed to dialog.submit() or None if dismissed.
+        """
+        # Create the dialog
+        dialog = ui.dialog()
+        dialog.open()
+
+        # Build the element inside the dialog with a card
+        with dialog, ui.card():
+            # Separate element constructor args from build args
+            element_args = kwargs.pop('element_args', ())
+            element_kwargs = kwargs.pop('element_kwargs', {})
+
+            # Create and build the instance
+            instance = cls(element_type, *element_args, **element_kwargs)
+
+            # Store dialog reference for potential use in build()
+            instance._dialog = dialog  # pyright: ignore[reportAttributeAccessIssue]
+
+            await instance.build(*args, **kwargs)
+
+            # Add a reference to the async instance on the element
+            instance._element._async_instance = instance  # pyright: ignore[reportAttributeAccessIssue]
+
+        # Await the dialog result
+        result = await dialog
+
+        # Clean up the dialog after it's closed
+        dialog.clear()
+
+        return result
+
     def __getattr__(self, name: str) -> Any:
         """Delegate any missing attribute access to the wrapped element"""
         return getattr(self._element, name)