myAddButton->setEnabled(( myListWidget->count() < myMaxSize || myMaxSize == -1 ) &&
( mySelectedIDs.size() > 0 ) &&
( mySelectedIDs.size() <= myMaxSize || myMaxSize == -1 ) );
myAddButton->setEnabled(( myListWidget->count() < myMaxSize || myMaxSize == -1 ) &&
( mySelectedIDs.size() > 0 ) &&
( mySelectedIDs.size() <= myMaxSize || myMaxSize == -1 ) );