GUI_Mainfcn Error in Matlab

Hey I have an issue here, I have already tried to solve this by searching from the previous issues answer but still cant resolve this. This is the code

function varargout = BrightnessMeasurement(varargin)
% BRIGHTNESSMEASUREMENT MATLAB code for BrightnessMeasurement.fig
%      BRIGHTNESSMEASUREMENT, by itself, creates a new BRIGHTNESSMEASUREMENT or raises the existing
%      singleton*.
%
%      H = BRIGHTNESSMEASUREMENT returns the handle to a new BRIGHTNESSMEASUREMENT or the handle to
%      the existing singleton*.
%
%      BRIGHTNESSMEASUREMENT('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in BRIGHTNESSMEASUREMENT.M with the given input arguments.
%
%      BRIGHTNESSMEASUREMENT('Property','Value',...) creates a new BRIGHTNESSMEASUREMENT or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before BrightnessMeasurement_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to BrightnessMeasurement_OpeningFcn via varargin.
%
%      *See GUI Options on GUIDE's Tools menu.  Choose "GUI allows only one
%      instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help BrightnessMeasurement

% Last Modified by GUIDE v2.5 01-Jan-2021 15:39:29

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @BrightnessMeasurement_OpeningFcn, ...
                   'gui_OutputFcn',  @BrightnessMeasurement_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT


% --- Executes just before BrightnessMeasurement is made visible.
function BrightnessMeasurement_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to BrightnessMeasurement (see VARARGIN)

% Choose default command line output for BrightnessMeasurement
handles.output = hObject;

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes BrightnessMeasurement wait for user response (see UIRESUME)
% uiwait(handles.figure1);
delete (instrfind({'Port'}, {'COM11'}));
clear a;
global a;
a = arduino ('COM11');
a.readDigitalPin (8, 'output');



% --- Outputs from this function are returned to the command line.
function varargout = BrightnessMeasurement_OutputFcn(hObject, eventdata, handles) 
% varargout  cell array for returning output args (see VARARGOUT);
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;


% --- Executes on button press in turn_on_button.
function turn_on_button_Callback(hObject, eventdata, handles)
% hObject    handle to turn_on_button (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
global a;
a.writeDigitalPin (8,1);


% --- Executes on button press in turn_off_button.
function turn_off_button_Callback(hObject, eventdata, handles)
% hObject    handle to turn_off_button (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
a.writeDigitalPin (8,0)


% --- Executes on button press in read_button.
function read_button_Callback(hObject, eventdata, handles)
% hObject    handle to read_button (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
global a k;
x = 0;
for k = 1:1:handles.XSamples
    b = a.analogRead (0);
    x = [x,b];
    plot(x,'LineWidth',2); grip on;
    axis ([0 handles.xSamples 0 500]);
    pause (0.01);
end


function sample_data_Callback(hObject, eventdata, handles)
% hObject    handle to sample_data (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of sample_data as text
%        str2double(get(hObject,'String')) returns contents of sample_data as a double
handles.data1 = get(hObject, 'stirng');
handles.xSamples = str2double (handles.data1);
guidata (hObject, handles);

% --- Executes during object creation, after setting all properties.
function sample_data_CreateFcn(hObject, eventdata, handles)
% hObject    handle to sample_data (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end

and this is the error warning

Error in gui_mainfcn (line 220)
    feval(gui_State.gui_OpeningFcn, gui_hFigure, [], guidata(gui_hFigure), varargin{:});

Error in BrightnessMeasurement (line 42)
    gui_mainfcn(gui_State, varargin{:});
 

please help

[Karim Khalid]

Were you able to solve this issue?

[Ashutosh Bajpai]

Is the issue resolved?

[Radu-Nicolae]

I have the same issue

[Walter Roberson]

That would not be the entire error message; we need the entire error message.

We would not be able to test the code without the associated .fig file.