Is passing DependencyProperty which gets updated to a ViewModel a good practice?
I have a custom user control, and it has a dependency property. That custom user control is kind of complicated so I decided to make a view model for it, but I haven't implemented it yet. I'm thinking of making the view model having some properties which are bound to the custom user control.
Here is my code sample,
UserControl.xaml
<StackPanel>
<TextBlock Text={Binding Age} />
<TextBlock Text={Binding Name} />
</StackPanel>
UserControl.cs
public Person Person
{
get { return (Person)GetValue(PersonProperty); }
set { SetValue(PersonProperty, value); }
}
public static readonly DependencyProperty PersonProperty = DependencyProperty.Register("Person", typeof(Person), typeof(SampleUserControl), new PropertyMetadata(null, propertyChangedCallback));
private static void p开发者_开发技巧ropertyChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
// I want to update the view model here
// Something like the following
(this.DataContext as MyViewModel).Person = Person;
}
MyViewModel
public Person Person
{
get { return _person; }
set
{
_pserson = person;
RaisePorpertyChanged("Age");
RaisePorpertyChanged("Name");
}
}
public int Age{ get; set; }
public string Name{ get; set; }
So, do you think it's a good practice? I mean updating a view model when a dependency property gets updated, and hopefully someone teaches me how to update the view model inside the PropertyChangedCallback :) BTW I'm using the MVVM Light toolkit.
According to this question, http://forums.silverlight.net/forums/p/133665/298671.aspx, I can't use a view model as the DataContext of a user control to bind some UI in a usual way.
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