TreeList Issues

[Pat Huesers]

I am trying to use the toggleExpandCollapse client function and it seems to not work at all.   I also am seeing console errors while trying settings to enable the toggleExpandCollapse function.

 

If I have a TreeList and set ExpandCollapseMode="combined" or "client" I get this error in the console as soon as I try to expand an item.   The expanding does work, but collapsing does not, it gives the below error.   On top of this if I set the ExpandCollapseMode to "client" the TreeList opens up with ALL items expanded out, but while in Server  or Combined mode it does not.   What am I doing wrong?

Uncaught TypeError: Cannot read property 'toggleExpandCollapse' of null
    at HTMLButtonElement.onclick

Uncaught TypeError: Cannot read property 'Combined' of undefined
    at Telerik.Web.UI.TreeListDataItem.initialize (Telerik.Web.UI.WebResource.axd

 

Here is the JS function I cam calling.

 

function collapseTree(radTreeListItemID) {
                            debugger;

                            var oTree = $find('<%= RadTreeList1.ClientID %>');
                            var keys = oTree.get_clientDataKeyNames();

                            oTree.get_dataItems().forEach(function (a) {
                                var expanded = a.get_expanded();
                                var title = a.get_element().innerText;
                                var id = a.get_dataKeyValue('ID');

                                //  loop through all the items and locate the one with the matching input datakey.
                                // set expanded to false..   doesnt seem to work..  setting visibility does.
                                if (id == radTreeListItemID && expanded) {
                                    debugger;
                                    // Make invisible - works
                                    //a.set_visible(false);

                                    //  this should just work but doesnt
                                    a.toggleExpandCollapse();
                                    a.set_clientExpanded(false);

                                    // doesnt work..  however a work around may be to loop through the child items and make invisible.
                                    // onpostback, they are re-written to page anyway..   problem is user control seems to not go away, so youd have to
                                    // locate that control in the element and hide too.

                                    a.get_childItems().forEach(function (innerItem) {
                                        innerItem.set_visible(false);
                                    });

                                }

                            });

                        };