![]() This defines a DataType and then the ItemSource as the collection within the DataType. A TreeView.Resources sits inside in which we define a HierarchicalTemplate. We define a TreeView & bind the ItemSource to our ItemsA. In the real world these lists are replaced with your queried data from the Database, Json, Xml etc:įinally our Xaml designer view. The ViewModel instantiates a collection of ItemA class objects, ItemA defines a collection of ItemB’s in the constructor & ItemB defines a list of ItemC. To acheive this we need to put our OOP hat on & build a hierarchy of classes to provide the TreeView with our data at run time. If you don’t know what to expect at run time then we can’t hard code the values, we need a dynamic TreeView! ![]() This is fine unless you have dynamic data. You could also bind these values to string property values exposed in your viewModel. TreeViewItems are nested within the TreeView & Headers are hardcoded. Hard coding your values is simple enough however I quickly learned that building a dynamic hierarchical TreeView was to be a little more complex!įirstly, here’s some simple hard coded Xaml: I got about using WPF’s TreeView control. I recently had a UI design which required the use of a tree view. SetTreeViewSelectedItem(( DependencyObject )sender, e.static void tv_SelectedItemChanged( object sender, RoutedPropert圜hangedEventArgs e).// When TreeView.SelectedItemChanged fires, set our new property to the value.new RoutedPropert圜hangedEventHandler (tv_SelectedItemChanged).TreeView tv = dependencyObject as TreeView.private static void TreeViewSelectedItemChanged( DependencyObject dependencyObject,.This article takes that idea further, and shows how we can use a ViewModel to encapsulate application-specific logic related to the check state of items in the tree. // for the TreeView's SelectedItemChanged event As explained in my ‘Simplifying the WPF TreeView by Using the ViewModel Pattern’ article, the TreeView was practically designed to be used in conjunction with a ViewModel.// When our property is set to a non null value we need to add an event handler In the following example, Ill show you just how easy it is to get started with the HierarchicalDataTemplate: In the XAML markup, I have specified a HierarchicalDataTemplate for the ItemTemplate of the TreeView.// This is the handler for when our new property's value changes.SetValue(TreeViewSelectedItemProperty, value) DependencyObject dependencyObject, object value).public static void SetTreeViewSelectedItem(. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |