This will uncheck the items:
int size = mNavigationView.getMenu().size();
for (int i = 0; i < size; i++) {
mNavigationView.getMenu().getItem(i).setCheckable(false);
}
This will uncheck the items:
int size = mNavigationView.getMenu().size();
for (int i = 0; i < size; i++) {
mNavigationView.getMenu().getItem(i).setCheckable(false);
}