Creating a new NativeSelect component with null selection allowed lists the empty value correctly, but it cannot be selected. Clicking the empty value doesn’t even fire a new ValueChangeEvent. However, setting an item ID for null value with setNullSelectionItemId() makes the null value selectable. Is this behaviour as intended or am I doing something wrong?
Tested with the following code on a new Vaadin 7.6.4 project:
NativeSelect ns = new NativeSelect("Native select");
ns.addItem("item1");
ns.addItem("item2");
ns.setValue("item1");
ns.setNullSelectionAllowed(true);
ns.setImmediate(true);
layout.addComponent(ns);