Stop data plotting in Matlab App Designer

Hi,

I'm trying to create an Arduino Oscilloscope in app designer, one of my functionalites is to have a 'stop' button so the user can stop the live plot at any time and observe the data. I've tried different ways such as:

fclose(app.s)

Nothing seems to work just yet as the data continues to plot infinitly, any help is appreciated.

properties (Access = private)
       %Define Function Variables
        s;                              %serial port
        time ;                          %time of plotting
        data = zeros(2,1);              %data stored in array
        count = 0; 
        GREEN_COLOR = [0 1 0]
        RED_COLOR = [1 0 0]
        plotGraph
       
    end
        
    methods (Access = private)
        
        function closeApp_Callback(app, ~, event)
        %closeApp_Callback Executes after "Close Confirm" dialog window
        %  "Close Confirm" dialog window is launched from AppCloseRequest.
            
            switch event.SelectedOption
                case 'OK'
                    
                    % Disconnect from oscilloscope instrument
                    % (Execute DisconnectButtonPushed callback function)
                   BConButtonPushed(app,[])
                   
                    delete(app)
                    
                case 'Cancel'
                    % Continue
            end
        end
     
        
    end
    
    
    

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

        % Code that executes after component creation
        function startupFcn(app)
% looking for available serial ports 
% (Instrument Control Toolbox required)
p = instrhwinfo('serial');
app.PortList.Items = p.AvailableSerialPorts;

        end

        % Button pushed function: StartPlotButton
        function StartPlotButtonPushed(app, event)
app.time =0;                     
plotGrid = 'on';                
max = 300;
min =200;
delay = .01;                   
 
%Set up Plot
ax = app.UIAxes;
app.plotGraph = plot(ax, app.time,app.data(1,:),'-r');
hold(app.UIAxes,'on')
plotGraph1 = plot(ax, app.time,app.data(2,:),'-m');
hold(app.UIAxes,'off')
axis(ax, [ 0 10 min max]);
grid(ax, plotGrid);

% start stopwatch timer
tic 
 
%Loop when Plot is Active
while  ishandle(app.plotGraph)
    
    %Read Data from Serial as Float
    dat = fscanf(app.s,'%f'); 
  
    if(~isempty(dat) && isfloat(dat)) %Make sure Data Type is Correct        
    app.count = app.count + 1;    
    app.time(app.count) = toc;    %Extract Elapsed Time in seconds
    app.data(:,app.count) = dat(:,1); %Extract 1st Data Element 
    
    set(app.plotGraph,'XData',app.time,'YData',app.data(2,:));
    set(plotGraph1,'XData',app.time,'YData',app.data(1,:));
    axis(ax,[0 app.time(app.count) min max]);
         
     %Allow MATLAB to Update Plot
     pause(delay); 
    
    end
end

        end

        % Button pushed function: SaveDataButton
        function SaveDataButtonPushed(app, event)
t = table(app.data); 
writetable(t,"test.xlsx","Sheet",1);
        end

        % Button pushed function: StopButton
        function StopButtonPushed(app, event)
if app.time.running == "on"
    stop(app.time);
    stopasync(app.s)
    fclose(app.s);
end
                
            
        end

        % Close request function: UIFigure
        function UIFigureCloseRequest(app, event)
question = 'Close app?';
            uiconfirm(app.UIFigure, question, 'Confirm Close',...
                'CloseFcn',@(src,event) closeApp_Callback(app,src,event));     
        end

        % Button pushed function: BCon
        function BConButtonPushed(app, event)
%              if strcmp(app.time.running, 'off')
                app.s = serial(app.PortList.Value);
                fopen(app.s);
%                 start(app.time);
                app.ConnLamp.Color = app.GREEN_COLOR;
%              end
        end

        % Button pushed function: BDiscon
        function BDisconButtonPushed(app, event)
              if app.time.running == "on"
                stop(app.t);
                if ~app.data
                    stopasync(app.s)
                    fclose(app.s);
                end
                app.Lamp.Color = app.RED_COLOR;
                
              end
            
            
                
                app.ConnLamp.Color = app.RED_COLOR;
        end

        % Button pushed function: Refresh
        function RefreshButtonPushed(app, event)
             % delete all serial port objets from MATLAB memory
            % (Instrument Control Toolbox required)
            delete(instrfind);
            % looking for available serial ports 
            % (Instrument Control Toolbox required)
            p = instrhwinfo('serial');
            app.PortList.Items = p.AvailableSerialPorts;
        end

        % Button pushed function: ResetButton
        function ResetButtonPushed(app, event)

                cla(app.UIAxes)
        end
    end

    % Component initialization
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)

            % Create UIFigure and hide until all components are created
            app.UIFigure = uifigure('Visible', 'off');
            app.UIFigure.Position = [100 100 1255 764];
            app.UIFigure.Name = 'MATLAB App';
            app.UIFigure.CloseRequestFcn = createCallbackFcn(app, @UIFigureCloseRequest, true);

            % Create Panel
            app.Panel = uipanel(app.UIFigure);
            app.Panel.Title = 'Panel';
            app.Panel.Position = [2 2 546 763];

            % Create HardwarePanel
            app.HardwarePanel = uipanel(app.Panel);
            app.HardwarePanel.Title = 'Hardware';
            app.HardwarePanel.Position = [10 560 527 95];

            % Create GridLayout11
            app.GridLayout11 = uigridlayout(app.HardwarePanel);
            app.GridLayout11.ColumnWidth = {'1x', '3x'};
            app.GridLayout11.Padding = [5 5 5 5];

            % Create Refresh
            app.Refresh = uibutton(app.GridLayout11, 'push');
            app.Refresh.ButtonPushedFcn = createCallbackFcn(app, @RefreshButtonPushed, true);
            app.Refresh.Layout.Row = 2;
            app.Refresh.Layout.Column = 2;
            app.Refresh.Text = 'Refresh';

            % Create PortLabel
            app.PortLabel = uilabel(app.GridLayout11);
            app.PortLabel.HorizontalAlignment = 'right';
            app.PortLabel.Layout.Row = 1;
            app.PortLabel.Layout.Column = 1;
            app.PortLabel.Text = 'Port';

            % Create PortList
            app.PortList = uidropdown(app.GridLayout11);
            app.PortList.Items = {'COM?'};
            app.PortList.Editable = 'on';
            app.PortList.BackgroundColor = [1 1 1];
            app.PortList.Layout.Row = 1;
            app.PortList.Layout.Column = 2;
            app.PortList.Value = 'COM?';

            % Create Panel_2
            app.Panel_2 = uipanel(app.Panel);
            app.Panel_2.Position = [12 654 525 80];

            % Create BCon
            app.BCon = uibutton(app.Panel_2, 'push');
            app.BCon.ButtonPushedFcn = createCallbackFcn(app, @BConButtonPushed, true);
            app.BCon.Position = [44 19 112 23];
            app.BCon.Text = 'Connect';

            % Create BDiscon
            app.BDiscon = uibutton(app.Panel_2, 'push');
            app.BDiscon.ButtonPushedFcn = createCallbackFcn(app, @BDisconButtonPushed, true);
            app.BDiscon.Position = [227 19 124 23];
            app.BDiscon.Text = 'Disconnect';

            % Create ConnLamp
            app.ConnLamp = uilamp(app.Panel_2);
            app.ConnLamp.Position = [418 19 32 32];
            app.ConnLamp.Color = [1 0 0];

            % Create ConnecttoHardwarefirstLabel
            app.ConnecttoHardwarefirstLabel = uilabel(app.Panel_2);
            app.ConnecttoHardwarefirstLabel.FontWeight = 'bold';
            app.ConnecttoHardwarefirstLabel.FontColor = [1 0 0];
            app.ConnecttoHardwarefirstLabel.Position = [5 52 152 22];
            app.ConnecttoHardwarefirstLabel.Text = 'Connect to Hardware first';

            % Create y_axis_1_menu
            app.y_axis_1_menu = uidropdown(app.Panel);
            app.y_axis_1_menu.Items = {'Select...', 'channel 1', 'channel 2', 'channel 3', 'channel 4', 'channel 5', 'channel 6', 'channel 7', 'channel 8', 'channel 9'};
            app.y_axis_1_menu.Tag = 'y_axis_1_menu';
            app.y_axis_1_menu.FontSize = 10.6666666666667;
            app.y_axis_1_menu.BackgroundColor = [0.729411764705882 0.831372549019608 0.956862745098039];
            app.y_axis_1_menu.Position = [39 507 132 22];
            app.y_axis_1_menu.Value = 'Select...';

            % Create Panel2
            app.Panel2 = uipanel(app.UIFigure);
            app.Panel2.Title = 'Panel2';
            app.Panel2.Position = [545 1 711 666];

            % Create UIAxes
            app.UIAxes = uiaxes(app.Panel2);
            title(app.UIAxes, 'Oscilloscope')
            xlabel(app.UIAxes, 'Time (s)')
            ylabel(app.UIAxes, 'Data')
            zlabel(app.UIAxes, 'Z')
            app.UIAxes.XLim = [0 50];
            app.UIAxes.YLim = [-1.5 1.5];
            app.UIAxes.XTick = [0 5 10 15 20 25 30 35 40 45 50];
            app.UIAxes.XGrid = 'on';
            app.UIAxes.YGrid = 'on';
            app.UIAxes.Position = [55 10 653 614];

            % Create Panel3
            app.Panel3 = uipanel(app.UIFigure);
            app.Panel3.Title = 'Panel3';
            app.Panel3.Position = [547 667 712 99];

            % Create StartPlotButton
            app.StartPlotButton = uibutton(app.Panel3, 'push');
            app.StartPlotButton.ButtonPushedFcn = createCallbackFcn(app, @StartPlotButtonPushed, true);
            app.StartPlotButton.BackgroundColor = [0.3294 0.9216 0.3294];
            app.StartPlotButton.FontWeight = 'bold';
            app.StartPlotButton.FontColor = [0.149 0.149 0.149];
            app.StartPlotButton.Position = [70 16 100 47];
            app.StartPlotButton.Text = 'Start Plot';

            % Create StopButton
            app.StopButton = uibutton(app.Panel3, 'push');
            app.StopButton.ButtonPushedFcn = createCallbackFcn(app, @StopButtonPushed, true);
            app.StopButton.BackgroundColor = [1 0 0];
            app.StopButton.FontWeight = 'bold';
            app.StopButton.FontColor = [0.149 0.149 0.149];
            app.StopButton.Position = [218 18 100 47];
            app.StopButton.Text = 'Stop';

            % Create SaveDataButton
            app.SaveDataButton = uibutton(app.Panel3, 'push');
            app.SaveDataButton.ButtonPushedFcn = createCallbackFcn(app, @SaveDataButtonPushed, true);
            app.SaveDataButton.BackgroundColor = [0.8 0.8 0.8];
            app.SaveDataButton.FontWeight = 'bold';
            app.SaveDataButton.FontColor = [0.149 0.149 0.149];
            app.SaveDataButton.Position = [516 16 100 47];
            app.SaveDataButton.Text = 'Save Data';

            % Create ResetButton
            app.ResetButton = uibutton(app.Panel3, 'push');
            app.ResetButton.ButtonPushedFcn = createCallbackFcn(app, @ResetButtonPushed, true);
            app.ResetButton.BackgroundColor = [0 1 1];
            app.ResetButton.FontWeight = 'bold';
            app.ResetButton.FontColor = [0.149 0.149 0.149];
            app.ResetButton.Position = [360 18 100 47];
            app.ResetButton.Text = 'Reset';

            % Show the figure after all components are created
            app.UIFigure.Visible = 'on';
        end
    end

    % App creation and deletion
    methods (Access = public)

        % Construct app
        function app = OscilloscopeGUI

            % Create UIFigure and components
            createComponents(app)

            % Register the app with App Designer
            registerApp(app, app.UIFigure)

            % Execute the startup function
            runStartupFcn(app, @startupFcn)

            if nargout == 0
                clear app
            end
        end

        % Code that executes before app deletion
        function delete(app)

            % Delete UIFigure when app is deleted
            delete(app.UIFigure)
        end
    end
end

Answer 1

[Pavan Guntha]

Hi Ashleigh,

I understand that the issue is regarding the integration of stop button with the uiaxes. You could look at the attached example app which illustrates the required behaviour.

Hope this helps!