Preventing specific items from being selected in a Flex Tree control

10 Responses to Preventing specific items from being selected in a Flex Tree control

1. Hans says:

   January 17, 2008 at 10:47 am

   In this example, items can still be selected via keyboard up and down arrows. The example does correctly prevent navigating to parent and child nodes that are disabled via left and right arrows though.

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2. Daniel says:

   April 21, 2008 at 5:34 am

   It also doesn’t work if you mouse-down on the item and release outside. Then it still selects…

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3. harley says:

   April 23, 2009 at 12:26 pm

   it works well enough for me.
   I do have a question. I am pretty dependent on FB’s auto “code completion” and the event.currentTarget.selectedItem just never would have occured to me since “selecedItem” doesn’t come up. is there away to create the var as a tree item?
   something like: var mytreeitem:tree = new tree; I can’t figure out a simple way to do this.. thanks in advance.

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   • Anonymous says:

     February 11, 2010 at 5:23 pm

     @harley
     type: (event.currentTarget as Tree).
     bingo – auto complete

     Reply
4. Heke says:

   July 17, 2009 at 5:11 am

   I’m not sure if I understood your problem, but can’t you just reference to your tree by the Tree’s ID? For example:

   and reference to it by using for example:
   Application.application.myTree.selectedItem

   Also the Tree inherits Event called “change” which is dispatched as the selectedItem (or selectedIndex, don’t know what that is) changes. So you could call your function through that event rather than itemClick.

   itemClick=”tree_itemClick(event)”
   replaced by:
   change=”tree_itemClick(event)”

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5. Heke says:

   July 17, 2009 at 5:13 am

   okay, sorry.. seem it deleted part of code:
   

   Application.application.myTree.selectedItem


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6. Heke says:

   July 17, 2009 at 5:14 am

   okay, I give up, can’t use this posting with tags:
   mx:Tree id=”myTree”

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7. Nicolas says:

   November 19, 2009 at 3:08 pm

   Is it possible to lock a Tree component in it’s open or closed position?

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   • Peter deHaan says:

     November 19, 2009 at 6:55 pm

     @Nicolas,

     I’m sure there is a better way, but here’s kind of a brute force method of keeping certain nodes open:

     <?xml version="1.0" encoding="utf-8"?>
     <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
      
         <mx:Script>
             <![CDATA[
                 import mx.events.ListEvent;
                 import mx.events.TreeEvent;
      
                 protected var lastScrollPos:uint;
      
                 protected function tr_itemCloseHandler(evt:TreeEvent):void {
                     if (evt.item.@lockOpen == true) {
                         var it:Object = tr.openItems;
                         it.push(evt.item);
                         tr.openItems = it;
                         // scroll back to locked item
                         callLater(correctScrollPos);
                     }
                 }
      
                 protected function correctScrollPos():void {
                     tr.verticalScrollPosition = lastScrollPos;
                 }
      
                 protected function tr_itemRollOverHandler(evt:ListEvent):void  {
                     lastScrollPos = tr.verticalScrollPosition;
                 }
             ]]>
         </mx:Script>
      
         <mx:XMLList id="dp" xmlns="">
             <node label="root">
                 <node label="One" />
                 <node label="Two" />
                 <node label="Three" lockOpen="false">
                     <node label="Three.1" />
                     <node label="Three.2" />
                     <node label="Three.3" />
                 </node>
                 <node label="Four" />
                 <node label="Five" />
                 <node label="Six *" lockOpen="true">
                     <node label="Six.1" />
                     <node label="Six.2" />
                 </node>
                 <node label="Seven" />
                 <node label="Eight *" lockOpen="true">
                     <node label="Eight.1" />
                     <node label="Eight.2" />
                 </node>
                 <node label="Nine">
                     <node label="Nine.1" />
                     <node label="Nine.2" />
                 </node>
             </node>
         </mx:XMLList>
      
         <mx:Tree id="tr"
                  dataProvider="{dp}"
                  labelField="@label"
                  openDuration="0"
                  width="200"
                  itemRollOver="tr_itemRollOverHandler(event);"
                  itemClose="tr_itemCloseHandler(event);" />
      
     </mx:Application>

     Peter

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8. sun says:

   December 9, 2010 at 7:11 pm

   If i don’t want the tree change its selecteditem when i key in any of the key, is it possible?

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