#Wpf treeview template example how to
#Wpf treeview template example update
#Wpf treeview template example code
#Wpf treeview template example series
#Wpf treeview template example download

That is inescapable, and there’s nothing wrong with doing it. Using it the correct way, paradoxically, means not directly using it at all! Naturally, you will need to set properties and call the occasional method directly on a TreeView. The TreeView is actually quite easy to work with, provided you use it the correct way. Who does not want a beautiful UI and a suite of clean, effective unit tests? What Exactly Makes the TreeView so Difficult? Also, the more loosely coupled the UI is to the application functionality, the more testable that functionality becomes. The easier it is to slap a UI on an application, the easier it is for a technically challenged Visual Designer to create a beautiful UI in Blend. This makes it easier to create a user interface (UI) for the application.

#Wpf treeview template example update

The ViewModel, in turn, communicates with the Model, and tells it to update in response to user interaction. The View binds to the ViewModel, and executes commands to request an action from it.

The ViewModel contains all the UI-specific interfaces and properties necessary to make it easy to develop a user interface. The (Data)Model-View-ViewModel pattern is similar to the classic Model-View-Presenter, except you have a model tailor-made for the View, called the ViewModel.

#Wpf treeview template example series

After Dan Crevier wrote his fantastic DataModel-View-ViewModel series of blog posts, the (D)MVVM pattern started growing in popularity.

It is quite similar to Martin Fowler’s Presentation Model pattern, only it fills in the gap between the presentation model and the view with WPF’s rich data binding. Background of ViewModelīack in 2005, John Gossman blogged about the Model-View-ViewModel pattern that his team at Microsoft was using to create Expression Blend (then known as ‘Sparkle’). If you are curious to see some examples of how the WPF TreeView can be customized, check out this article and this article.

#Wpf treeview template example how to

Once you learn how to properly work with the WPF TreeView, those complexities disappear, and it is quite easy to leverage the full power of the control. They make the control more complicated than the WinForms TreeView. Those excellent features come at a price. In contrast, the WPF TreeView is extremely flexible, inherently supports UI virtualization (i.e., TreeViewItems are created on-demand), allows for full visual customization, and has full support for data binding. The WinForms TreeView is “good enough for government work”. That simplicity arises from the fact that the Windows Forms TreeView is completely inflexible, offers no support for UI virtualization, offers zero possibility for visual customizations, and since it does not support data binding, it requires you to store data in its nodes. In Window Forms, it is very easy to use the TreeView control because it is dead simple. This is yet another example of how WPF requires you to shift mental gears to make use of the platform appropriately. In order to leverage the extensive features of the WPF TreeView, you cannot use the same programming techniques as in Windows Forms.

#Wpf treeview template example code

The problem is that people often try to use it in the same way that one might code against the Windows Forms TreeView control. Many people try to use it, and find it to be exceedingly difficult. The TreeView control in WPF has gained an undeserved bad reputation. One of the demos shows how to create a searchable TreeView, the other demonstrates how to implement lazy-loading (a.k.a. Along the way, we examine why people often have difficulty with the WPF TreeView, what a ViewModel is, and two demo applications that show how to combine a TreeView with a ViewModel. This article explores how to use the ViewModel pattern to make it easier to work with the TreeView control in WPF.

#Wpf treeview template example download

Download the source code (requires Visual Studio 2008) - 28.6 KB.WPF is then clever enough to apply the correct template to each of our view models allowing us to easily style each individually. Then we specify our FileViewModel as the DataType for the DataTemplate, our FileViewModel has no children therefore we don't need to use a HierarchicalDataTemplate for this. We specify our DirectoryViewModel as the DataType for the HierarchicalDataTemplate and bind the ItemsSource to the Children property of DirectoryViewModel, again, this can contain either DirectoryViewModels or FileViewModels. In our TreeView's resource section we define a HierarchicalDataTemplate and a DataTemplate specifying the DataType we want each template to be applied to. The ItemsSource property of the TreeView binds to the Children property of our MainViewModel, we can put either DirectoryViewModels or FileViewModels in here.