Add a swap method for dynamic items

discord/ui/container.py

@@ -198,6 +198,10 @@ class Container(Item[V]):
     def _has_children(self):
         return True
 
+    def _swap_item(self, base, new, custom_id) -> None:
+        child_index = self._children.index(base)
+        self._children[child_index] = new  # type: ignore
+
     @property
     def children(self) -> List[Item[V]]:
         """List[:class:`Item`]: The children of this container."""

discord/ui/item.py

@@ -44,6 +44,7 @@ if TYPE_CHECKING:
     from ..components import Component
     from .action_row import ActionRow
     from .container import Container
+    from .dynamic import DynamicItem
 
 I = TypeVar('I', bound='Item[Any]')
 V = TypeVar('V', bound='BaseView', covariant=True)
@@ -118,6 +119,9 @@ class Item(Generic[V]):
             return self._provided_custom_id
         return True
 
+    def _swap_item(self, base: Item, new: DynamicItem, custom_id: str) -> None:
+        raise ValueError
+
     def __repr__(self) -> str:
         attrs = ' '.join(f'{key}={getattr(self, key)!r}' for key in self.__item_repr_attributes__)
         return f'<{self.__class__.__name__} {attrs}>'

discord/ui/section.py

@@ -111,6 +111,10 @@ class Section(Item[V]):
     def _is_v2(self) -> bool:
         return True
 
+    def _swap_item(self, base, new, custom_id) -> None:
+        if self.accessory.is_dispatchable() and getattr(self.accessory, 'custom_id', None) == custom_id:
+            self.accessory = new  # type: ignore
+
     def walk_children(self) -> Generator[Item[V], None, None]:
         """An iterator that recursively walks through all the children of this section
         and its children, if applicable. This includes the `accessory`.

discord/ui/view.py

@@ -300,6 +300,12 @@ class BaseView:
         if self.__timeout:
             self.__timeout_expiry = time.monotonic() + self.__timeout
 
+    def _swap_item(self, base: Item, new: DynamicItem, custom_id: str) -> None:
+        # if an error is raised it is catched by the try/except block that calls
+        # this function
+        child_index = self._children.index(base)
+        self._children[child_index] = new  # type: ignore
+
     @property
     def timeout(self) -> Optional[float]:
         """Optional[:class:`float`]: The timeout in seconds from last interaction with the UI before no longer accepting input.
@@ -954,11 +960,9 @@ class ViewStore:
         parent = base_item._parent or view
 
         try:
-            child_index = parent._children.index(base_item)  # type: ignore
+            parent._swap_item(base_item, item, custom_id)
         except ValueError:
             return
-        else:
-            parent._children[child_index] = item  # type: ignore
 
         item._view = view
         item._rendered_row = base_item._rendered_row