addDispatcher static method

void addDispatcher(Component component, { required bool hasDrag, required bool hasScale, })

Ensures a MultiDragScaleDispatcher is registered on the game that owns component, then enables drag and/or scale as requested.

For a component that mixes both DragCallbacks and ScaleCallbacks, this method is called twice from their separate onMount chains, once with hasDrag=true and once with hasScale=true. The second call finds the existing dispatcher and simply enables the remaining flag.

Implementation

static void addDispatcher(
  Component component, {
  required bool hasDrag,
  required bool hasScale,
}) {
  final game = component.findRootGame()!;
  var dispatcher =
      game.findByKey(const MultiDragScaleDispatcherKey())
          as MultiDragScaleDispatcher?;
  if (dispatcher == null) {
    dispatcher = MultiDragScaleDispatcher();
    game.registerKey(const MultiDragScaleDispatcherKey(), dispatcher);
    game.add(dispatcher);
  }
  if (hasDrag) {
    dispatcher.enableDrag();
  }
  if (hasScale) {
    dispatcher.enableScale();
  }
}