How can i implement a timed counter in app designer

I really need to make use of a counter that will increase every 0.25 seconds in app designer ,I've used the timer function in a matlab script but I'm not sure how to go about implementing this in app designer, i want the count variable to increase after every 25 milliseconds as long as the toggle switch is in a certain position . Please help from the beginning, im not familiar with app designer whatsoever

Answer 1

[Geoff Hayes]

@Keenan Jogiah - you could create a timer object within the app that you would then start and stop based on the toggle. In this example, I'm assuming that the toggle is a checkbox - when checked, the timer will start and update the text area with a value that will increase by one over time. When the checkbox is unchecked, the timer will be stopped. I needed to add the following code to do this

    properties (Access = private)
        mTimer    % timer
        mCounter; % integer counter
    end

which are the data members for the timer object and counter. The callback for the checkbox does "all" of the work

    % Callbacks that handle component events
    methods (Access = private)

        % Value changed function: CheckBox
        function CheckBoxValueChanged(app, event)
            value = app.CheckBox.Value;
            if value == 1
                % checkbox is checked so reset counter, create and start
                % timer
                app.mCounter = 0;
                app.mTimer = timer('TimerFcn', @timerCallback, 'ExecutionMode', 'FixedRate', 'Period', 0.25);
                start(app.mTimer);
            else
                % checkbox is unchecked so stop timer
                stop(app.mTimer);
            end
            
            % this is the callback for the timer
            function timerCallback(~, ~)
                % update the text area and increment the timer
                app.TextArea.Value = num2str(app.mCounter);
                app.mCounter = app.mCounter + 1;
            end
            
        end
    end

[Keenan Jogiah]

Thank you so much, I was pretty lost with the app designer syntax