![]() ![]() Enjoy □ĭownload Sample Project (VS2008): farmtree. You find the complete sample under the link below. Of course, you can easily style any of the data templates to your liking. I wrote a simple converter that performs these tasks. Return everything as a an object that can be bound to the TreeView.ItemsSource property.Render specific child items directly under the parent node (no subfolder).Provide means to name (or even identify) a folder in order to simplify styling.Where necessary, put a bound child item or collection into a virtual container object that can serve as a "folder" when it comes to rendering.Allow binding of simple objects ( Farmer), or collections ( Animals, Crops).Our converter has to provide the following functionality: You can use a MultiBinding to retrieve all necessary data of a given Farm instance:Ī MultiBinding always needs a converter of type IMultiValueConverter. Let’s start with the bindings, which are declared within a HiearchicalDataTemplate. ![]() And of course: Data templates that provide a visual representation of your bound data.A converter that helps us organizing the different bound collections into sub folders, where necessary.A MultiBinding that allows you to combine different bindings.My solution to that very problem requires the following ingredients: However, sometimes, you just want to have a quick solution. This route does work very well for quite a few scenarios. Now, one solution to that very problem are ViewModel wrapper classes that optimize the business logic for your specific UI logic. From the control’s point of view, this means that the "Folder" nodes and the "Farmer" node are siblings. Note the difference: We want to organize the Animals and Crops collections within individual sub folders, while the "Farmer" node is a direct child of the "Farm" root node. Image your Farm class looks like this:Īccordingly, you might want to display that information according to the sketch below: However, more often than not, you’re running into more complex scenarios where additional structuring is necessary. WPF TreeView samples you see on the web are somewhat simplistic: While they may provide heterogeneous data, usually all childs of a given node are of the same type: The code looks like this: private void MyTreeView_MouseUp(object sender, e) the first child in the template), I never get events when I click on the empty area (which is rather logical). If I add a handler to my TreeView.ItemTemplate instead (i.e. How is this supposed to work?Įdit: Some more information: I’ve added a handler to the TreeView to handle mouse click events, but the sender is always a TreeView instance, even if I click directly on a TreeViewItem. Moreover, this is counter-intuitive, as it requires the user to right-click first, and second, after deselecting it with this way, the user cannot select it any more by clicking on the item. (treeView.SelectedItem) as TreeViewItem).IsSelected = false By default, the treeview keeps the current item selected, and I have added a context-menu option to deselect it, which is rather hardcore: // Note: This is done recursivly from the start, so it C or VB.NET and usually maintained by the designer (e.g. In previous GUI frameworks, like WinForms, a GUI was created in the same language that you would use for interacting with the GUI, e.g. The problem is, I want to unselect the currently selected item when the user clicks inside the blank area of the treeview. XAML, which stands for eXtensible Application Markup Language, is Microsofts variant of XML for describing a GUI. I have a tree-view, and selecting items works fine so far. I’ve got a rather funny problem with WPF.
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