Here is the example from documentation of uilistbox:
function selectlistbox
fig = uifigure('Position',[100 100 350 275]);
% Create text area
txt = uitextarea(fig,...
'Position',[125 90 100 22],...
'Value','First');
% Create list box
lbox = uilistbox(fig,...
'Position',[125 120 100 78],...
'Items',{'First','Second','Third'},...
'ValueChangedFcn', @updateEditField);
% ValueChangedFcn callback
function updateEditField(src,event)
txt.Value = src.Value;
end
end