callbacks, timers and OOP methods: help with using a method as timer callback

Hello, world of Matlab wizards.

6 years Matlab user, just started playing with OOP in Matlab. I'm trying to using a method as caklabck for a timer which is located in the constructor, and it doesn't work. What am I missing? Please enlighten me.

Thanks

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classdef Vehicle

    properties
        Speed % [Km/Hour]
        Length % [Meter]
        Width % [Meter]
        Driver % Properties of the driver
        Current_Route % Current route
        Route_Percent % Which Percent of the route the vehicle is in
        Route_Direction % Driving forward or backeard on the routhe
        Last_Action_Time % The time stamp for the last action of the vehicle
    end

    methods
        function this = Vehicle(varargin)
            this.Speed = varargin{1}; % The speed of the car
            this.Current_Route = varargin{2}; % What route the vehicle is on
            this.Route_Percent = varargin{3}; % Where on the routeh is the vehicle
            this.Route_Direction = varargin{4}; % To what direction is the car moving on the route
            this.Last_Action_Time = clock; % Set the time the thisect was creted
            Progress_Timer = timer('TimerFcn', @Progress, 'Period', varargin{4}, 'ExecutionMode' ,'FixedRate'); % Sets a timer for progressing vehicle position
            start(Progress_Timer) % Starts the timer
        end

        function this = Progress(this)
            if (this.Route_Percent >= 0 && this.Route_Percent <= 100) % If the vehicle does not exceed the route map
                this.Route_Percent = this.Route_Percent + ...
                    this.Route_Direction * this.Speed * etime(clock,this.Last_Action_Time)/3600 / this.Current_Route.Length * 100
                this.Last_Action_Time = clock; % Set the time the progress was done
            else
                this.delete; % Vehicle is no longer relevant
                stop(Progress_Timer); % Stops the timer
            end
        end
    end
end

[Andrew Newell]

Could you give an example of a call and describe what is going wrong?

Answer 1

[Robert Moss]

Call back functions need to be a subfunction of the method from which they are called. In this case that is the constructor. Move the Progress method inside your constructor and it should be happier.

[Robert Moss]

Sorry, by subfunction I actually meant nested function.

Answer 2

[per isakson]

The creation of the timer object could be

    % Sets a timer for progressing vehicle position
    Progress_Timer = timer                                  ...
        (   'TimerFcn'      ,   @(src,event) Progress(this) ...
        ,   'Period'        ,   varargin{4}                 ...  
        ,   'ExecutionMode' ,   'FixedRate'                 );

Possibly, Progress(this,src). The signature of Progress must match.

...

    this.delete; % Vehicle is no longer relevant
    stop(Progress_Timer); % Stops the timer

No delete-method is defined for Vehicle. (Inherit from handle.)

Progress_Timer not defined here.

It is a pain to debug code like this. See previous Debug code invoked by timer