Question

(For this example) ListBox l is bound to CustomObjectCollection c.

Does l call c’s Constructor?

What if c is a Generic Object?

**In XAML (1)**
<ListBox Content={Binding CustomObjectCollection}/>

**In Codebehind**
CustomObjectCollection<MyClass> c;
**In XAML (2)**
<ListBox Content={Binding CustomObjectCollection}/>

Suppose in c, I populate the collection(dynamically, using the constructor)
Which binding would call the constructor?

Sorry if this is unclear, I have no idea how to explain it.

Answer 1

You should bind to a property. If the source object needs to be constructed, then it has to be done in the code behind.

<ListBox ItemsSource={Binding ListSource} />

//Codebehind
class MyControl : UserControl {
    public CustomObjectCollection ListSource {get; private set;}

    public MyControl() {
      ListSource  = new CustomObjectCollection (/*arguments*/);
      InitializeComponent();
      DataContext = this;
    }
}