Image not displayed properly in GUI

I have created a Matlab GUI where I would display multiple images from a folder in the image axes at GUI. I could read all the image files. Unfortunately, the image axes in the GUI is blank as shown in the figure below. Any help would be appreciated.

function varargout = dm(varargin)
% DM MATLAB code for dm.fig
%      DM, by itself, creates a new DM or raises the existing
%      singleton*.
%
%      H = DM returns the handle to a new DM or the handle to
%      the existing singleton*.
%
%      DM('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in DM.M with the given input arguments.
%
%      DM('Property','Value',...) creates a new DM or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before dm_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to dm_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 dm

% Last Modified by GUIDE v2.5 06-Apr-2021 01:25:06

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @dm_OpeningFcn, ...
                   'gui_OutputFcn',  @dm_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 dm is made visible.
function dm_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 dm (see VARARGIN)

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

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes dm wait for user response (see UIRESUME)
% uiwait(handles.figure1);


% --- Outputs from this function are returned to the command line.
function varargout = dm_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 pushbutton1.
function pushbutton1_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
myFolder = 'D:\regionGrowing_MLT\Images';
% Check to make sure that folder actually exists.  Warn user if it doesn't.
if ~isfolder(myFolder)
    errorMessage = sprintf('Error: The following folder does not exist:\n%s\nPlease specify a new folder.', myFolder);
    uiwait(warndlg(errorMessage));
    myFolder = uigetdir(); % Ask for a new one.
    if myFolder == 0
         % User clicked Cancel
         return;
    end
end
% Get a list of all files in the folder with the desired file name pattern.
filePattern = fullfile(myFolder, '*.jpg'); % Change to whatever pattern you need.
theFiles = dir(filePattern);

for k = 1 : length(theFiles)
    baseFileName = theFiles(k).name;
    fullFileName = fullfile(theFiles(k).folder, baseFileName);
    fprintf(1, 'Now reading %s\n', fullFileName);
   
    % Now do whatever you want with this file name,
    % such as reading it in as an image array with imread()
    imageArray = imread(fullFileName);
    
    axes(handles.axes1);
    imshow(imageArray);  % Display image.
    drawnow; % Force display to update immediately.
    
    
   
    
    handles.imageArray=imageArray;
end
    % Update handles structure
guidata(hObject, handles);

[Walter Roberson]

You process all jpg files in the directory. The last one might be very small.

[Rik]

You're overwriting handles.imageArray every iteration, and you're using the same axes object to show every image. I would also suggest passing the handle to axes directly to imshow, instead of what you are currently doing to ensure the proper parent object.

As for your folder selection: I would suggest splitting it into a different function that uses a while loop to check if the folder is valid.

Also, the attached images are just 1 pixel. Why do you expect to notice them anyway?

And I have probably linked this before, but GUIDE is about to be removed from Matlab. Anything non-trivial should not be designed with GUIDE. For general advice and examples for how to create a GUI (and avoid using GUIDE), have look at this thread.

[Warid Islam]

Hi @Rik,

You are right. I was wrong images in the GUI. That was quite silly from me. My GUI now works fine.