Treeview ExpandItemByPath() not Getting Expanded

[Chandu]

Hello All,

I am working on Telerik RadTreeView to bind all Folders with in Attachment Folder in System HardDrive(D:\\Attachment).
Am using WCF Service for it and i can able to bind all Folders to TreeView successfully.

Here my Problem is i have a Button,when i click on that button i need to Expand the tree by its path for that am using
 ExpandItemByPath()
but am unable to Expand the tree,i have tried it in many ways to solve this issue.

I enclosed a jpg image for more information.Please find the attachment.

Any help would be appreciated a lot

Thanks,
chandu

[Tina Stancheva]

Hello Chandu,

I'm not sure what path you're trying to expand. If you need to expand the entire RadTreeView and all its items, you can use the RadTreeView.ExpandAll() method. If you need to expand the path to a particular item, then you can use the ExpandItemByPath() method. However, you need to keep in mind that in order to take advantage of either of these methods, the RadTreeView has to be fully loaded and initialized.

This means that if you're using virtualizaiton, these methods won't work properly as a virtualized RadTreeView generates only those RadTreeViewItems that are inside the current viewport. So if you try to expand an item outside the viewport, the ExpandAll() and ExpandItemByPath() methods won't work. If this is your case, it might be better to use the BringPathIntoView() method as demonstrated in this tutorial.

I hope this information will help you get over the described issue. But if it doesn't, it would greatly help us to send a sample solution demonstrating your approach so that we can take a closer look at it and the issue.

Kind regards,
Tina Stancheva
the Telerik team

[Chandu]

Hello Tina,

Thanks a lot for the reply.But am still not able to get over the issue.
In my first post i told that am binding my local System Drive Folders to RadTreeView ,that am doing in page load through the
WCF Service.
In button click am trying to expand the tree by its path.
I have used the same method to expand tree...ExpandItemByPath()

You can approach my issue from the sample solution through the link given below.
https://www.dropbox.com/sh/1h59gswo3frcg6f/5ViaRS6FNw

Thanks
Chandu

[Tina Stancheva]

Hello Chandu,

Thank you for sending over the sample solution. We managed to find the cause for the issue in your solution - it is in the PathSeparator in the RadTreeView control. As you're displaying folders, there is a mix up with the RadTreeView.PathSeparator and the folders structure path separator. In order to avoid such issues, it's better to use a different PathSeparator in the RadTreeView control - for example '|'. Then if you define the path to the items using this separator, the control won't be confused by the path separator in the folders like in the first node - D:\Attachments.

Also, in order to take advantage of the ExpandItemByPath() method, you need to define which property from the business model should serve as a path segment. As you're building the path using the name of each node, you need to set the TextSearch.TextPath attached property to Name.

Basically the RadTreeView definition should be updated like this:

<telerik:RadTreeView x:Name="tree"
          Width="350"
          Height="999"
          ItemsSource="{Binding Children}"
          ItemTemplate="{StaticResource itemTemplateAllLevels}"
          PathSeparator="|"
          telerik:TextSearch.TextPath="Name" />

And your code-behind logic should look like this:

private void btnExpand_Click(object sender, RoutedEventArgs e)
{
    string path = @"D:\Attachments|New folder";  //my physical Folder Path
    tree.ExpandItemByPath(path);
    //tree.BringPathIntoView(path);
}

I modified your solution to demonstrate these changes so please give it a try and let me know if you have more questions.

Regards,
Tina Stancheva
the Telerik team

[Chandu]

Hello Tina,

I tried the sample it is working perfect....Superb

Thanks a lot.....................


Regards,
Chandu