#WPF TREEVIEW MVVM EXAMPLE CODE#

(instead of in the constructor of your view, for example).Īdd this ViewModel to your ViewModelLocator (I use the mvvmlocatorproperty code snippet provided in MVVM Light).īind your View to the ViewModel using the Locator. Initializing an instance of the classes you created would go here. Your ObservableCollections would sit here. This is where you'd have your properties that you're binding to in your veiw. This means abstracting out your data access layer (more below).Ĭreate your ViewModel. I generally use POCO's, simply defining the properties of a model. So, to convert this to MVVM you need to do a few things.Ĭreate defined Models. On the assumption that you're using MVVM Light (you can extrapolate from this if you're using another toolkit).

implement the INotifyPropert圜hanged interface). My first recommendation would be to drop in an MVVM toolkit, as it's easier than having to do everything yourself (e.g. ObservableCollection items = new ObservableCollection() įavoriteFolder fdr = new FavoriteFolder() Report Items: public class FavoriteReportĪnd the – public partial class MainWindow : Window Sql = 'SELECT * FROM tbl_reports where rpt_folder_id =' + _folderID įavoriteReport report = new FavoriteReport() SqlDataReader reader = cmd.ExecuteReader() įavoriteFolder folder = new FavoriteFolder() įolder.FolderID = reader.ToString() įolder.FolderTitle = reader.ToString() įolder.ParentID = reader.ToString() SqlCommand cmd = new SqlCommand(sql, cnn) String sql = 'SELECT * FROM tbl_report_folders where fdr_parent_id =' + _folderID Using (SqlConnection cnn = new SqlConnection(_connectionString)) Private string _connectionString = new ServerInfo().ConnectionString My two classes that exist in the TreeView are:įolder items: public class FavoriteFolder I have looked at many examples, but I am still new to MVVM and WPF in general, so any guidance for my particular example would be much appreciated FavoriteReport - an object that cannot have any children: when a user clicks on this item it will run a report.Ĭurrently I have a Model-View type setup (I think), and I would like to change it to MVVM so I can do things with the TreeView-items rather than simply display them.FavoriteFolder - an object that can have children: either folders or reports.

There are 2 objects that live in the tree: This defines a DataType and then the ItemSource as the collection within the DataType.I have a TreeView that I (finally) have been able to populate from a database using data binding. 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.

Wpf treeview mvvm example