public boolean containsItem(E item) {
		DefaultComboBoxModel<E> model = (DefaultComboBoxModel<E>) getModel();
		return model.getIndexOf(item) != -1;
	}
Returns true if the combobox contains the given item.
@param item the item to check
@return true if the combobox contains the given item.
Ghidra/Framework/Docking/src/main/java/docking/widgets/combobox/GhidraComboBox.java