MATLAB: How to dynamically update a static text box depending on number of checkboxes selected.

Question

Hello,

I am currently trying to update a static text box in a MATLAB GUI I made. I am fairly new to GUIs, and I tried creating addlisteners, but to no avail.

I pre-set checkboxes in the opening function, and I want to be able to display the amount of boxes that are checked into a static text box . I have:

• checkbox1 – checked
• checkbox2 – not checked
• checkbox3 – checked
• checkbox4 – checked
• checkbox5 – checked

I would like the static text box to display "4", and if I select the last checkbox, or deselect another checkbox, I would like the value to dynamically change.

% main loop
% --- Executes just before PnP_GUI is made visible.
function PnP_GUI_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 PnP_GUI (see VARARGIN)
% Choose default command line output for PnP_GUI
handles.output = hObject;
%Pre-Check Save Options
set(handles.checkbox1,'value',1)
%set(handles.checkbox2,'value',0) % want not checked to start
set(handles.checkbox3,'value',1)
set(handles.checkbox4,'value',1)
set(handles.checkbox5,'value',1)
% Update handles structure
guidata(hObject, handles);

Any help would be greatly appreciated.

Thank you,

– JR

Answer 1

One method:

Add this to your OpeningFcn before the guidata call

handles.hCheckboxes = [ handles.checkbox1, handles.checkbox2, handles.checkbox4, handles.checkbox4, handles.checkbox5 ]

Then create a function such as this in your GUIDE file and call it from each of your checkbox callbacks. Or you can point all checkboxes to a single callback if you wish, but they will each have their own by default.

function updateStaticText( handles )
totalSelected = sum( cell2mat( get( handles.hCheckboxes, 'Value' ) ) );
handles.text1.String = num2str( totalSelected );