RadTreeView with thousands of nodes is very slow, takes too long to expand/collapse

[Faye]

Performance of RadTreeView with thousands of nodes is very slow, takes too long to expand/collapse:

~3000 nodes – expand: ~2 mins 32 secs, collapse: ~28 secs

~9000 nodes – expand: ~27 mins 26 secs, collapse: ~4 mins 57 secs

Note: For hundreds of nodes, performance is slightly better but still quite slow: ~100 nodes – ~1.5 secs. Scrolling is also badly delayed.

 

I am using a trial version of the RadControls for Silverlight 4, Windows XP, IE6. TreeView’s IsVirtualizing=true and VirtualizationMode=Hierarchical. Items in the TreeView use a simple HierarchicalDataTemplate which consists of an Ellipse, Image, TextBlock and TextBox. ItemsSource points to a class that generates dummy data using classes with typical properties (ex. string, bool, struct, DateTime).

 

The tree structure used for testing is 6 levels deep and there are thousands leaf nodes:

Level1

                Level2

                                Level3

                                                Level4

                                                                Level5

                                                                                <thousands of leaf nodes>

 

The TreeView is declared as follows:

<telerik:RadTreeView ItemsSource="{Binding Source={StaticResource DataSource},

                                                                       Path=TreeNodes}"

                                         ItemTemplate="{StaticResource TreeItemTemplate}"

                                         IsVirtualizing="True"

                                         telerik:TreeViewPanel.VirtualizationMode="Hierarchical"

                                         IsLoadOnDemandEnabled="True"

                                         SelectionMode="Extended"

                                         SelectionChanged="treeView_SelectionChanged"

                                         KeyDown="treeView_KeyDown"

                                         ScrollViewer.VerticalScrollBarVisibility="Visible"/>

 

Even tried turning off animation (telerik:AnimationManager.IsAnimationEnabled="False") as mentioned in some forums but this did not yield a better result.

 

I noticed though, that using RadTreeListView has no problems with ~3000 or ~9000 nodes:

~3000 nodes – expand: ~0.9 secs, collapse: ~0.3 secs

~9000 nodes – expand: ~1.2 secs, collapse: ~0.5 secs

Am I missing something when it comes to TreeView?

 

Any suggestions on how to improve the TreeView performance for a large number of nodes? This is too slow considering UI virtualization is already enabled and the data are merely objects, no interaction with any database or server.

[Petar Mladenov]

Hi Faye,

We are aware of the fact that the current version of RadTreeView needs performance optimization when ExpandAll Collapse all operations are used. We have logged this previously in our PITS(TreeView: Too many TreeViewItems are created internally when using virtualization) and you are able to vote for it in order to increase its development priority.
However, if you do need a large number of expand operations you could use RadTreeListView instead of RadTreeView. On the other hand, if you need to expand only particular nodes at a time , I think the RadTreeView could fit nicely in your scenario. You can examine this performance demo (showing generation of millions of items) and this blog post showing how to expand a particular node if you know its path from the tree`s root node.
Please let us know if you need more info on this. We would be glad to advice you.


Kind regards,
Petar Mladenov
the Telerik team

[Developer]

Hi,

We use a RadTreeView and RadGrid telerik controls in a page. While expanding and colapsing the tree nodes in RadTreeView, the sync is lost between the grid and TreeView.When I expand the tree node, the tree is expands behind the grid(Grid doesn't move down). When I move the mouse away the grid moves down. Same thing happens with the collapse. When I collapse the tree, grid doesn't move up, which results in a gap between the TreeView and the Grid. When I move the mouse the Grid moves up .
Please help me resolve this issue.

Thanks In Advance

[Petar Mladenov]

Hi Developer ,

Could you please elaborate a bit on your scenario?  Is it possible for you to send us your XAML or an isolated sample in a new support ticket?It will be also great if you can send us a captured video with the issue you have come up with. What is the number of items in the RadTreeView and in the RadGridView? 

Kind regards,
Petar Mladenov
the Telerik team