NI recommends using the Actor Framework template on the launcher.
In the Project Files tab, locate the Actor you want to create Messages for.
Right-click the Actor and select Actor Framework»Create abstract message for caller. A namespace that corresponds to the new abstract Message appears within the Abstract Messages namespace. In addition, a class with Read Attributes and Send Actor Abstract Msg and a type definition called Abstract Message Name Data, which acts as the payload for the abstract Message, also appear.
Add data to the type definition to specify the contents of the abstract Message.