使用提交数据后出现错误 <h:selectManyMenu> 在JSF中？

Question

index.xhtml

<h:selectManyMenu style="height:70px" value="#{bookBean.selectedBook}">
 <f:selectItems value="#{bookBean.books}"/>
</h:selectManyMenu>

<h:commandButton action="#{bookBean.doClick}" value="Submit" />

BookBean.java

List<SelectItem> books = new ArrayList<SelectItem>();

public List<SelectItem> getBooks() {
 return books;
}

So, the problem is after I choose multiple items in the ManyMenu list and click the commandButton in xhtml file, it gives an error. It says "Target model Type is no a Collection or Array"

What does that mean? I need to change List<> to any collection type?

The page suppose to display the items I selected in the first page.

Answer 1

This

value="#{bookBean.selectedBook}">

has to be a collection.

Think about it, you are selecting many items, so you have to store them in a collection. Even if you are selecting one SelectItem then it has to be stored in a collection as well.

So, make sure .selectedBook is a collection. Regards!