Keeping component state with rich:tree RF 4.1.0

[saifeldeen]

Hi there,

I'm not quite sure on how to keep component state with rich:tree using v4.1.0 final.  My situation is this: I have a tree that users may expand / collapse items at any point during their session.  However, when a page is refreshed (e.g. new request), the tree is collapsed again.  I would like the tree to maintain state throughout the users' session.

I have read a number of other discussions, particularly https://community.jboss.org/thread/161388 which appears to "resolve" the problem, however, it appears to be a (necessary) hack as the RF source code needs direct modification

In the above issue Nick Belaevski suggests "In RF4 you should bind 'expanded' and 'selection' to model beans explicitly using EL-expressions.", however, there doesn't appear to be  "expanded" and "selection" attributes known by the models / libraries.

Can someone please provide some guidance or even better, a solution, on how to maintain the state of a rich:tree using v4.1.0 final?

Kind regards,

sh

[saifeldeen]

Ok, the answer seems to be quite simple.  Leading on from the tree node example in the JSF showcase

1. The xhtml:

{code}
<h:form>
    <rich:tree 
     id="tree" 
     nodeType="#{node.type}" 
     var="node" 
     value="#{treeBean.rootNodes}" 
     toggleType="ajax"
     selectionType="ajax" 
     toggleListener="#{programTreeBean.processTreeToggle}"
     selectionChangeListener="#{treeBean.selectionChanged}">
        <rich:treeNode type="country" expanded="#{node.expanded}">
            #{node.name}
        </rich:treeNode>
        <rich:treeNode type="company" icon="/images/tree/disc.gif">
            #{node.name}
        </rich:treeNode>
        <rich:treeNode type="cd" icon="/images/tree/song.gif">
            #{node.artist} - #{node.name} - #{node.year}
        </rich:treeNode>
    </rich:tree>
</h:form>
{code}

2. The NamedNode class needs to implement a property for "expand":

{code}
private boolean expanded;
public boolean isExpanded()
{
    return expanded;
}
public void setExpanded(boolean expanded)
{
    this.expanded = expanded;
}
{code}

3. Set the TreeBean to be @SessionScoped

4. In the TreeBean, implement the TreeToggleListener interface and add the following code

{code}
@Override
public void processTreeToggle(TreeToggleEvent selectionChangeEvent) throws AbortProcessingException
{
    // considering only single selection
    UITree tree = (UITree) selectionChangeEvent.getSource();
    NamedNode node = (NamedNode) tree.getRowData();
    node.setExpanded(tree.isExpanded());
}
{code}

And voila, the tree is persisted in the session correctly.