event.listener not working when called within class instance

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Darim 2016-5-28

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https://ww2.mathworks.cn/matlabcentral/answers/286217-event-listener-not-working-when-called-within-class-instance

编辑： per isakson 2016-5-28

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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')