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list box string isn't updated after changes

Asked by evgeny shumsky on 16 Sep 2019
Latest activity Edited by evgeny shumsky on 18 Sep 2019
Hi all, i have created gui with guide.
I have 4 push buttons: add, remove, up, down
1.JPG
the problem is with "add" button. the list box excepts the string from "editbox" and add it between the selected value of the list box
2.JPG
but when i try to add another string it replaces the existing on with the new one.
how can i keep the added string to the list and adding another one without removing the previous?
this is the push button callback
function add_Callback(hObject, eventdata, handles)
editbox = get(handles.edit,{'string'}); %need {} because editbox is a char
Lstring = get(handles.listbox,'string');
Lvalue = get(handles.listbox,'value');
% update the string in the selected place with the editbox data
%Lstring(Lvalue)=[editbox]
Value=Lvalue+1;
low=1:Lvalue;
low1=num2str(low');
high=Value:50;
high1=num2str(high');
new = [low1 editbox high1];
set(handles.listbox,'string',new,'value',Value);

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1 Answer

Answer by Kevin Phung on 16 Sep 2019
 Accepted Answer

it gets removed because of the way you are building your string.
low=1:Lvalue;
low1=num2str(low');
high=Value:50;
high1=num2str(high');
new = [low1 editbox high1];
you are always setting the strings before and after your selection to be 1:Lvalue and value:50.
I would suggest doing this:
Add editbox string directly below the selection.
function add_Callback(hObject, eventdata, handles)
editbox = get(handles.edit,{'string'}); %need {} because editbox is a char
Lstring = get(handles.listbox,'string');
Lvalue = get(handles.listbox,'value');
% update the string in the selected place with the editbox data
%Lstring(Lvalue)=[editbox]
new = [Lstring(1:Lvalue) editbox Lstring(Lvalue)];
Value = Lvalue+1
set(handles.listbox,'string',new,'value',Value);
let me know if this works for you

  1 Comment

it wan't working
??? Error using ==> horzcat
CAT arguments dimensions are not consistent.
Error in ==> GUI_final>add_Callback at 103
new = [Lstring(1:Lvalue) editbox Lstring(Lvalue)];
so i changed it a little bit and now every thing works
Value=Lvalue+1;
new = [Lstring(1:Lvalue); editbox; Lstring(Value:end)];
thank you, you have helped me alot

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