How to dynamically add JSF components
Can I add JSF components dynamically? I need to have a form with a button which should add one <h:inputText> to the form. Is this possible?
I know this should be possible in JavaScript somehow. Do anybody know how to do this in JSF? I think the major problem is how do I get or set values of new inputs via #{value}.
Answer
Use an iterating component like <h:dataTable> or <ui:repeat> to display a dynamically sized List of entities. Make the bean @ViewScoped to ensure that the list is remembered across postbacks on the same view instead of recreated over and over.
Kickoff example with <h:dataTable> (when using <ui:repeat> simply replace <h:dataTable> by <ui:repeat>, and <h:column> by e.g. <li> or <div>):
<h:form>
<h:dataTable value="#{bean.items}" var="item">
<h:column><h:inputText value="#{item.value}" /></h:column>
<h:column><h:commandButton value="remove" action="#{bean.remove(item)}" /></h:column>
</h:dataTable>
<h:commandButton value="add" action="#{bean.add}" />
<h:commandButton value="save" action="#{bean.save}" />
</h:form>
Managed bean:
@Named
@ViewScoped
public class Bean {
private List<Item> items;
@PostConstruct
public void init() {
items = new ArrayList<>();
}
public void add() {
items.add(new Item());
}
public void remove(Item item) {
items.remove(item);
}
public void save() {
System.out.println("items: " + items);
}
public List<Item> getItems() {
return items;
}
}
Model:
public class Item {
private String value;
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
public String toString() {
return String.format("Item[value=%s]", value);
}
}