setOnMembership
Sets the handler for incoming membership events. This method allows the assignment of an OnMembershipHandler implementation or lambda expression to handle incoming presence events.
To deactivate the current behavior, simply set this property to null.
Note that this property allows for the assignment of a singular behavior at a time, as any new assignment will override the previous one. For scenarios requiring multiple behaviors in response to membership events, it is advisable to utilize EventEmitter.addListener.
Setting a Behavior Example:
`onMembershipHandler(pnMembershipResult -> System.out.println("Received: " + pnMembershipResult.getEvent()));
` *Removing a Behavior Example:
`onMembershipHandler(null); `*
Parameters
onMembershipHandler
An implementation of OnMembershipHandler or a lambda expression to handle incoming messages. It can be null to remove the current handler.