Is it possible to do a MasterDetail Binding with a TreeView?

Is it possible to do a MasterDetail Binding with a TreeView?

• LewisPringle

  Bea,

  Thanks for the post. I'm running into this same problem. I noticed that your post was dated August of last year. I'm running the new Framework 3.5 Beta. The documentation that came with 'Orcas' says pretty plainly: Any data binding that uses a ListCollectionView will automatically update. However, your post here seems to indicate that the TreeView control isn't going to update the details when using data binding (as opposed to binding directly to the control's 'SelectedItem'). At this point, I'm guessing that the ListCollectionView is inapproriate for a hierarchical organization like a TreeView. Can you confirm that the TreeView control should still be broken in .NET Framework 3.5. If so, I'll continue using the work-around that you posted a year ago.

  Best regards,

  
  
  

• Munira

  It works just fine!

  Many Thanks.

  
  

• Tien Tran

  Hi Doug,

  1. Regarding databinding across UserControls. Yes, that is possible. The trick is to add a new DP to the UserControl and data bind that to whatever you want, within that UserControl. This should be done for both UserControls. Then, when you use the UserControls, you can simply data bind the new DP of one of them to the new DP of the other. You can apply this trick in other scenarios where you want to data bind across namescopes. Let me know if this is not clear and I'll make a small sample for you.

  2. Regarding the SelectionChanged. When the user clicks on a different item in the UI, WPF makes sure that SelectionChanged is invoked. This method is used to give the developer the opportunity to execute some code whenever the user changes selection.

  3. Thanks for your kind words about my blog. I've replied to your question in my blog.

  I hope this helps!

  Bea

  
  
  

• SeanKelley

  It seem that this is working only for the first level of the tree. I would like to list all childs of any nodes of my tree and for leaves, display their properties.
  
  For atomic node I bind textBox in code like this
  void SelectionChanged(object sender, RoutedPropertyChangedEventArgs<object> e)
  {
  TreeView tree = (TreeView)sender;
  Binding myBinding;
  myBinding = new Binding("CountryName");
  myBinding.Mode = BindingMode.TwoWay;
  Country c = (Country)tree.SelectedItem;
  myBinding.Source = c;
  textBox1.SetBinding(TextBox.TextProperty, myBinding);
  }
  
  This work well for displaying every properties of leaves.
  
  I tried doing the same thing with a listbox for the other nodes but without succes...
  
  What is the best way to do that.
  
  Thanks.
  
  

• Yaron

  I just solved this problem by adding

  SelectedItemChanged="MySelectionChanged" to my TreeView and set the content off my ContentControl in the codebehind file.

  But why is there not a IsSynchronizedToCurrentItem in the TreeView

  
  

• Hena

  Hi Jean,

  The code I posted before also doesn't work for me now. Taking a closer look at it, I don't think it should have ever worked, maybe there was a bug before that caused it to work. You're absolutely right that the right way to do this would be to bind to the SelectedItem. I changed my previous sample to work the right way: http://www.beacosta.com/Forum/MasterDetailTreeView2.zip.

  Thanks for pointing this out.

  Bea

  
  
  

• Hork

  Hi,

  IsSynchronizedWithCurrentItem is a property on Selector. ListBox derives from it, but TreeView doesn't - even though it supports selection, it has its own logic to do so. In my opinion, we should made Master-Detail in TreeView as easy to do as in ListBox, and I have a bug tracking that. We'll see what happens...

  In the meantime, the workaround you came up with will do it. If you have several ContentControls, however, and want all of them to be in sync with the TreeView, you may want to do it a little differently:

  TreeView tree = (TreeView)sender;

  ItemCollection ic = countriesTreeView.Items;

  ic.MoveCurrentTo(e.NewValue);

  Instead of changing the content of each ContentControl manually, this code changes the currency of the view to be in sync with selection (which is what IsSynchronizedWithCurrentItem does). This is a little more code if you only have one ContentControl but scales better.

  You can find a complete sample with this solution in http://www.beacosta.com/Forum/MasterDetailTreeView.zip.

  Let me know if this helps.

  Thanks.

  
  
  

• icystone

  You mean using the DataContext method of Master-Detail binding
  
  I had the exact same problem you had. When I tested a prototype with a ListBox, I could do the Master-Detail binding by setting the IsSynchronizedToCurrentItem to True. When I switched to a TreeView, it stopped working.
  
  The only way I found to fix this is by binding the Detail control to the TreeView's SelectedItem. I should post a suggestion to look into this.
  
  

• rvghst

  Beatriz,

  Is there an elegant way to do the databinding across UserControls. In your example if the TreeView and Content control are in separate UserControls Stating it slightly differently, is there a way to reference elements in other NameScopes with the ElementName ref in the binding

  Also, SelectionChanged is not being called or referenced, so I'm not clear on how this sample works at all! But it does!

  void SelectionChanged(object sender, RoutedPropertyChangedEventArgs<object> e)

  {

  TreeView tree = (TreeView)sender;

  ItemCollection ic = countriesTreeView.Items;

  ic.MoveCurrentTo(e.NewValue);

  }

  On a separate issue, I made a posting to your blog regarding the TreeViewItem style / HierarchicalDataTemplate question.

  Your posts are very helpful.

  Thanks,

  Doug Hagan

  
  
• Is it possible to do a MasterDetail Binding with a TreeView?