iptSetpointerbehavior issue in appdesigner

Hello everyone,

İ am trying to record the position of the cursor and run a motor when is inside a specific area. İ am encountering an issue thats :

''Undefined function 'iptSetPointerBehavior' for input arguments of type 'matlab.graphics.primitive.Patch'.''

Below is my code:

properties (Access = public)
        arduinoObj % Description
        message
        region
      
    end

    properties (Access = public)
        T % Description

    end

    properties (Access = public)

        region1

    end

    properties (Access = public)
        amplitude % Description
    end

    methods (Access = private)

        function mycallback(app,src,event)
            display(event.SelectedOption);
        end

        end
        
function startupFcn(app)
            % Plot patch on uiaxes
            hold(app.UIAxes, 'on')
            
            app.region1 = patch(app.UIAxes,[5 5 10 10],[5 5 5 0],'r','FaceAlpha',1,...
                'LineWidth',2,'LineStyle','-','tag','region1');
            
            % Define pointer behavior for patch
            pm.enterFcn = @(~,~) cursorPositionFeedback(app, app.region1, 'in');
            pm.exitFcn  = @(~,~) cursorPositionFeedback(app, app.region1, 'out');
            pm.traverseFcn = [];
            iptSetPointerBehavior(app.region1, pm)
            % Enable pointer manager for app
            iptPointerManager(app.UIFigure,'enable');
            function cursorPositionFeedback(app, hobj, inout)
                % When inout is 'in', change hobj facecolor to red and update textbox.
                % When inout is 'out' change hobj facecolor to blue, and clear textbox.
                % Check tag property of hobj to identify the object.
                switch lower(inout)
                    case 'in'
                        facecolor = 'g';
                        txt = 'Inside region1';
                        pointer = 'fleur';
                        %Writeline(app.arduinoObj,...)
                    case 'out'
                        facecolor = 'r';
                        txt = '';
                        pointer = 'crosshair';
                        %Writeline(app.arduinoObj,...)
                end
                hobj.FaceColor = facecolor;
                app.TextAreaEditField = txt;
                set(app.UIFigure, 'Pointer', pointer)
            end

        end

   % Window button motion function: UIFigure
        function UIFigureWindowButtonMotion(app, event)
            % detect if the mouse is within the axes
            cp = app.UIFigure.CurrentPoint;
            isInAxes = cp(1) >= app.UIAxes.Position(1) &&...
                cp(1) <= sum(app.UIAxes.Position([1,3])) &&...
                cp(2) >= app.UIAxes.Position(2) &&...
                cp(2) <= sum(app.UIAxes.Position([2,4]));
            if isInAxes
                set(app.CurrentPositionEditField, 'Value',...
                    sprintf('%.2f, %.2f', app.UIAxes.CurrentPoint(1,1:2)))
            else
                set(app.CurretPositionEditField, 'Value', '')
            end

[Walter Roberson]

Do you have the Image Processing Toolbox installed?

Answer 1

[Karan Singh]

Hi Tugba,

From what I understand, you are trying to create a graphical user interface (GUI) in MATLAB that includes a plot and a patch object. You want to track the position of the cursor within the plot and perform certain actions when the cursor is inside or outside a specific region defined by the patch object.

However, you are encountering an error message stating that the “iptSetPointerBehavior” function is undefined for the input arguments of type “matlab.graphics.primitive.Patch”. This error suggests that the function is not recognized by MATLAB.

To resolve this issue, you have a few options:

1. Install the Image Processing Toolbox: If you have a license for the Image Processing Toolbox, you can install it from the MATLAB Add-Ons menu.
2. Use an alternative method: You can use the “WindowButtonMotionFcn” callback to track the cursor position and update the behavior accordingly.

Here's an example of how you can modify your code to achieve cursor position feedback:

% Window button motion function: UIFigure 
function UIFigureWindowButtonMotion(app, event) 
% detect if the mouse is within the axes 
cp = app.UIFigure.CurrentPoint; 
isInAxes = cp(1) >= app.UIAxes.Position(1) &&... 
    cp(1) <= sum(app.UIAxes.Position([1,3])) &&... 
    cp(2) >= app.UIAxes.Position(2) &&... 
    cp(2) <= sum(app.UIAxes.Position([2,4])); 
if isInAxes 
    set(app.CurrentPositionEditField, 'Value',... 
        sprintf('%.2f, %.2f', app.UIAxes.CurrentPoint(1,1:2))) 
    cursorPositionFeedback(app, 'in'); 
else 
    set(app.CurretPositionEditField, 'Value', '') 
    cursorPositionFeedback(app, 'out'); 
end 
end 

function cursorPositionFeedback(app, inout) 
% When inout is 'in', change region1 facecolor to red and update textbox. 
% When inout is 'out' change region1 facecolor to blue, and clear textbox. 
% Check tag property of region1 to identify the object. 
switch lower(inout) 
    case 'in' 
        facecolor = 'g'; 
        txt = 'Inside region1'; 
        pointer = 'fleur'; 
        %Writeline(app.arduinoObj,...) 
    case 'out' 
        facecolor = 'r'; 
        txt = ''; 
        pointer = 'crosshair'; 
        %Writeline(app.arduinoObj,...) 
end 
app.region1.FaceColor = facecolor; 
app.TextAreaEditField = txt; 
set(app.UIFigure, 'Pointer', pointer) 
end 

In this modified code, the “WindowButtonMotionFcn” callback function tracks the cursor position and calls the  “cursorPositionFeedback”  function to update the behaviour accordingly.

Attached below are some documentation links that you may find helpful:

• Graphics - MATLAB & Simulink (mathworks.com)
• UI axes appearance and behavior - MATLAB (mathworks.com)
• Develop Apps Using App Designer - MATLAB & Simulink (mathworks.com)

Hope this helps!

Karan Singh Khati