3 Replies Latest reply on Aug 25, 2008 9:37 AM by Peter Whitmore

    node selection in a tree

    renaux maxime Newbie

      Hi,
      I'm using a <rich:tree> component in a projet and I need to define the selected node. For exemple when the the page is loaded a particular node is selected. Or directly in the java code.

      Is there a way to do that in Java or Javascript (or other).

      Thanks a lot
      Maxime

        • 1. Re: node selection in a tree
          hans meiser Newbie

          In Java you can use the TreeStateAdvisor class:

          public class SomeBean implements TreeStateAdvisor{
           public Boolean adviseNodeOpened(UITree tree){
           Object data = tree.getRowData();
           YourTreeModel treeModel = (YourTreeModel) data;
           if(...){
           // open node
           return Boolean.TRUE;
           }
           else if(...){
           // close node
           return Boolean.FALSE;
           }
           // do not change treestate
           return null;
           }
          
           public Boolean adviseNodeSelected(UITree tree){
           Object data = tree.getRowData();
           ...
           }
          }



          <rich:tree ... stateAdvisor="someBean" >



          • 2. Re: node selection in a tree
            renaux maxime Newbie

            Thanks a lot for the answer but I'm confused in using this method. I have read some topic about the adviseNodeSelected method and it says

            "MethodBinding pointing at a method accepting an org.richfaces.component.UITree with return of java.lang.Boolean type. If returned value is: java.lang.Boolean. TRUE, a particular treeNode is selected; java.lang.Boolean.FALSE, a particular treeNode is unselected; null, a particular treeNode saves the current state"

            Where do i specify the node that hade to be selected?

            Thanks

            • 3. Re: node selection in a tree
              Peter Whitmore Newbie

              I do it during by setting a _selectedNode object on selection and then by doing the following on the adviseNodeSelected routine.

              Maybe you could do something similar.

              BTW: Sorry for lack of comments in the code. Not good I know.

              I am sure there are better ways, but this works great in my app.

              public Boolean adviseNodeSelected(UITree tree) {
               if (!PostbackPhaseListener.isPostback()) {
               Object key = tree.getRowData();
              
               IConfigNode treeRowKey = (IConfigNode) key;
               if (treeRowKey == null) {
               return Boolean.FALSE;
               }
               if (_selectedNode == null) {
               _selectedNode = treeRowKey;
               return Boolean.FALSE;
               }
               return treeRowKey.getId() == _selectedNode.getId();
               }
               return null;
               }
              


              FYI: I also keep a map of the node states for ensuring that they don't loose the states on some refreshing instances.

              
               public Boolean adviseNodeOpened(UITree tree) {
              
               if (!PostbackPhaseListener.isPostback()) {
               Object key = tree.getRowKey();
               TreeRowKey<?> treeRowKey = (TreeRowKey<?>) key;
               if (treeRowKey == null) {
               return Boolean.FALSE;
               }
               return getListenerBean().isExpanded(treeRowKey.getPath());
               }
              
               return null;
              
               }
              
              
               public ListenerBean getListenerBean() {
               if (_listenerBean == null) {
               _listenerBean = new ListenerBean();
               }
              
               return _listenerBean;
               }
              
              
               public class ListenerBean implements
               org.richfaces.event.NodeExpandedListener {
              
               private Map<String, Boolean> _statesMap = new HashMap<String, Boolean>();
              
               public void processExpansion(NodeExpandedEvent event)
               throws AbortProcessingException {
               Object source = event.getComponent();
               if (source instanceof HtmlTree) {
               source = ((HtmlTree) source).getRowData();
               }
              
               if (source instanceof HtmlTreeNode) {
               HtmlTreeNode n = (HtmlTreeNode) source;
               // assume it was opened if it was already in the map
               Object o = n.getUITree().getRowKey();
               if (o != null) {
               TreeRowKey<?> key = (TreeRowKey<?>) o;
               String path = key.getPath();
               if (_statesMap.containsKey(path)) {
               _statesMap.put(path, !_statesMap.get(path));
               } else {
               _statesMap.put(path, Boolean.TRUE);
               }
               }
               }
               }
              
               public void setExpanded(String treeNodeid) {
               _statesMap.put(treeNodeid, Boolean.TRUE);
               }
              
               public Boolean isExpanded(String treeNodeId) {
               // assume it was opened if it was already in the map
               if (_statesMap.containsKey(treeNodeId)) {
               return _statesMap.get(treeNodeId);
               } else {
               return Boolean.FALSE;
               }
               }
              
               }