how to load from text file to listbox

Hello,

I'm using GUI Guide in the MATLAB:

How to load a text file (that contain numbers) when clicking on the pushbutton and then display the text file contents in my listBox

I want to display the numeric on the text file as two columns in the ListBox, for example:

123 456
897 127
164 865

and I tried this code:

function load_Callback(hObject, eventdata, handles)
% hObject    handle to load (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
[filename pathname] = uigetfile('*.txt', 'File Selector]');
fullpathname=strcat(pathname , filename);
x = fileread(fullpathname);
set(handles.badPixelList,'string',x);

but the results on my ListBox looks like this:

123456897127164865

Thank you.

Answer 1

[Tridib]

Hi @Norah Mohammed

After creating a new GUI with a “Push Button” and a “List Box” using Guide, in the “.m” file generated by GUIDE, make the following changes to the function named “pushbutton1_Callback”:

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)

% "uigetfile" function lets the user select a text file
[file, path] = uigetfile('*.txt', 'Select a Text File');

% Check if user canceled
if isequal(file, 0)
    errordlg('No file selected!', 'File Error');
    return;
end

% Read the file data
filename = fullfile(path, file);
fileData = load(filename);

% Check if data is numeric and in two columns
if ~isnumeric(fileData) || size(fileData, 2) ~= 2
    errordlg('File must contain numeric data with two columns!', 'Data Error');
    return;
end

% Format data as two columns for ListBox
% This loops through the data row by row, using
%sprintf to create a string with spacing between columns
formattedData = cell(size(fileData, 1), 1);

for i = 1:size(fileData, 1)
formattedData{i} = sprintf('%d %d', fileData(i, 1), fileData(i, 2));
end

% "set" updates the ListBox to display the formatted content
set(handles.listbox1, 'String', formattedData);

Save the “.fig” and “.m’ files and run to test the functionality. Also, here, it is assumed that the text file contains the numeric data in two columns only, like:

123 456
897 127
164 865

For more information on the “uigetfile” and “set” function, refer to the following documentations:

“uigetfile”: https://www.mathworks.com/help/matlab/ref/uigetfile.html

“set”: https://www.mathworks.com/help/matlab/ref/set.html

As GUIDE has been deprecated from MATLAB R2021a, it is recommended to use App Designer for the latest releases.

Hope this helps!

Answer 2

[Image Analyst]

You can use readlines to read the lines of the text file and then put them into the listbox. For App Designer, it would be something like this (untested)

linesInFile = readlines(filename);
app.listbox.Items = linesInFile;