correctly erasing items from a listbox

I am trying to erase some listings from a listBox. however, when I push the appropriate button I receive the following warning:

Warning: multi-selection listbox control requires that Value be an integer within String range

and the listBox control doesn't get rendered. Any ideas for a fix? here is the code of the button's callback :

function btnRemovePNU_FromUse_Callback(hObject, eventdata, handles)
% hObject    handle to btnRemovePNU_FromUse (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
PNUList = handles.liPNU_toUse;
indexedPNU = get(PNUList,'value');
PNUnames = get(PNUList,'String');
PNUnames(indexedPNU) = [];
set(PNUList,'String',PNUnames);

Answer 1

[Teja Muppirala]

After you delete the items from the 'String' property, you need to update the 'Value' property as well.

For example, if you initially had 3 items, and you selected the 3rd one, then 'value' is 3. Then you delete it, and now you have two items left, but the value is still = 3. This is the problem.

Update the 'value' and you'll be fine:

set(PNUList,'String',PNUnames, 'Value', 1);

[Teja Muppirala]

This is ok too (if you are allowing multiple or empty selections)

set(PNUList,'String',PNUnames, 'Value', []);

[roi]

Thanks Teja!

I took your answer and updated the value to be at one place before the erased text:

function btnRemovePNU_FromUse_Callback(hObject, eventdata, handles)

% hObject handle to btnRemovePNU_FromUse (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDATA)

PNUList = handles.liPNU_toUse;

indexedPNU = get(PNUList,'value');

newPlace = indexedPNU(1)-1;

if (newPlace <=0) newPlace = 1; end

PNUnames = get(PNUList,'String');

if ~isempty(PNUnames)

PNUnames(indexedPNU) = [];

set(PNUList,'String',PNUnames,'value', newPlace);

end

[Thomas Côté]

10000 years later, thank you.

It was helpful for my own code.