event.listener not working when called within class instance

Dear Forum,

I encounter some problems when using event.listener class. For testing I've implemented the following code:

Event-triggering class:

classdef Subject < handle
    events
        event
    end
    properties
    end    
end

Responding class:

classdef Object < handle
    properties
        listen;
    end
    methods
        function setListener(obj, subject, event)
            %obj.listen = event.listener(subject, event, @obj.respond);
            obj.listen = addlistener(subject, event, @obj.respond);
        end
    end
    methods       
        function respond(varargin)
            disp('Event has occured');            
        end
    end
end

And a tiny test script:

% create instances
subject = Subject();
object = Object();

% set listener
object.setListener(subject, 'event')

% notify object
notify(subject, 'event');

When switching the statements

 %obj.listen = event.listener(subject, event, @obj.respond);
 obj.listen = addlistener(subject, event, @obj.respond);

in class Object, I will get the following error:

Struct contents reference from a non-struct array object.

Error in Object/setListener (line 12)
            obj.listen = event.listener(subject, event, @obj.respond);

Error in testListener (line 6)
object.setListener(subject, 'event')

To my understanding this should work.

Moreover, I can establish the connection, when creating the listener from my script:

 l = event.listener(subject, 'event', @object.respond)

Is it not possible to call event.listener from within an object?

I am using Matlab 2016a.

Can someone please help?

Thanks,

Daniel