I am not seeing the issue with your code, but it could be improved a bit. Your initial value on the dropdown is the first one - 'Harta1', and if you opened the dropdown menu and pressed it again callback won't be executed, but that's not an issue because you have already loaded Harta1 in the startupFcn.
Better way to do it is by having an intial option that tells you to choose the map, as a result, you don't have to have the startupFcn anymore.
% Value changed function: SelecteazaHartaDropDown
function SelecteazaHartaDropDownValueChanged(app, event)
value = app.SelecteazaHartaDropDown.Value;
switch value
case 'Please select the map'
cla(app.UIAxes)
case 'Harta1'
s=shaperead('C:\Users\Vostro\Desktop\App_Maps\Map1\map1.shp');
geoshow(app.UIAxes,s);
case 'Harta2'
s=shaperead('C:\Users\Vostro\Desktop\App_Maps\Map2\map2.shp');
geoshow(app.UIAxes,s);
end
end
