Matlab listeners multiple execution

I have an issue using Matlab listeners: PreGet and PostGet. My purpose is to be able to execute a set of functions when I am writing and when I am writing a calls property (before and after each read/write operation). This is an example of my class:

classdef myClass < handle 
    properties (GetObservable,SetObservable,GetAccess = public, SetAccess = public )
        myProp = '';
    end

      methods
          function myClass = myClass(Input)

              myClass.myProp = Input;

              addlistener(myClass , 'myProp' , 'PreGet' , @myClass.PreReadClass);
              addlistener(myClass , 'myProp' , 'PreSet' , @myClass.PreSendClass);
              addlistener(myClass , 'myProp' , 'PostGet' , @myClass.PostReadClass);
              addlistener(myClass , 'myProp' , 'PostSet' , @myClass.PostSendClass);
          end
      end

     methods (Hidden)

          function PreSendClass(myClass,  varargin)
              disp('PreSet Executed')
          end
          function PostSendClass(myClass,   varargin)
             disp('PostSet Executed')
          end

          function PreReadClass(myClass,   varargin)
              disp('PreGet Executed')
          end
          function PostReadClass(myClass,   varargin)
             disp('PostGet Executed')
          end
      end

end

Matlab Run examples:

>> myTest = myClass(1);
myTest.myProp = 1;
PreSet Executed
PostSet Executed

>> myVar = myTest.myProp;
myVar
PreGet Executed
PostGet Executed

myVar =

       1

Everything fine with this. I can execute my functions and get the results which I want. Though, I observed, that wen I use 'Tab Completion' feature from Matlab on 'myTest.myProp', PreGet and PostGet is executed, 4 times!! Sometimes 'myProp' is a dynamic structure and I am using Tab completion to access its fields.

myTest.myProp. % Use tab completion
PreGet Executed
PostGet Executed
PreGet Executed
PostGet Executed
PreGet Executed
PostGet Executed
PreGet Executed
PostGet Executed

Is it possible to prevent this from being executed 4 times? Or if not to prevent it at least to detect it and perform and action? I can run another function when tab completion is executed (e.g. display help or tool tip in command window).

Thank you!

[Sean de Wolski]

What release are you on? I am not able to reproduce this in 13b.

[Florin]

Sorry, I forgot to mention. I am on Matlab 2011b (7.13.0.54) 32bits. I had the same issue using Matlab 2009b.

[Sean de Wolski]

If your Company/University's SMS is current you can upgrade to one of the newer releases at no additional cost.

[Florin]

Hello. Currently I am stuck with a 32 bits system. I made an update to Matlab 2012b and I did not like the performance. For the moment I would prefer to use 2011b

Answer 1

[per isakson]

I cannot reproduce the behavior you describe with R2013a. However, there might have been a bug although I don't find one in the Bug Report. (Not all bugs are in that list.)

See: Tab Complete seems to silently execute code

.

2013-10-10

Did you ask the Matlab tech support?

There is a blog post at Undocumented Matlab on tab completion: Setting desktop tab completions