Calling the Event Dispatcher will have no effect if there are no events bound to it. Consider that each Event Dispatcher has a list of events associated with it. The way to add an event to this list is by using a Bind Event node, and the way to remove an event from this list is by using an Unbind Event node. It is also possible to unbind all of the events currently bound to an Event Dispatcher with an Unbind All Events node.
Each event can be bound only once, even if the Bind Event node is executed multiple times. Also, events in the Blueprint Class and the Level Blueprint are both added to the same event list, so
an Unbind All Events node will unbind events in both the Blueprint Class and the Level Blueprint.
An Unbind All Events node executed in the Blueprint Class will unbind events in both the Blueprint Class and the Level Blueprint for all instances of the class.
An Unbind All Events node executed in the Level Blueprint will unbind events in both the Blueprint Class and the Level Blueprint, but just for the Target supplied.
Creating Bind, Unbind, and Unbind All Nodes
The processes for creating Bind Event, Unbind Event, and Unbind All Events nodes are very similar. The steps below explain how to create a Bind Event node, but Unbind Event and Unbind All Events nodes can be created by choosing the respective menu items at the appropriate steps.
In Blueprint Classes
Drag off of the Event Dispatcher's name in the My Blueprint tab, and drop into the graph you are working in.
Select Bind in the menu that appears.
Alternatively:
Right-click in the graph.
Search for Bind Event to [EventDispatcherName] and select the entry from the context menu.
In Level Blueprints
Add a reference to the Actor in your level you would like to call the Event Dispatcher for.
Drag off of the output pin of the reference node and release to show the context menu.
Navigate to Event Dispatcher > Bind Event to [EventDispatcherName] in the context menu. Searching for "Bind [EventName]" should quickly bring up the correct entry.
The Call node will appear, with the Actor reference already wired to the Target pin.