Silverlight 3’s New Element Data Binding

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• PingBack from http://www.silverlight-travel.com/blog/2009/03/29/silverlight-3s-new-element-data-binding/

• Hi,
  since SL2 I've been waiting for the support for binding to things like Angle property of the RotateTransform for example.
  Based on your current experience, it seems like that still doesn't work :( since RotateTransform ultimately inherits from DependencyObject and not FrameworkElement (I'm at work now and don't have access to SL3 to check if they changed the base class, though I don't see why they would, it makes no sense).
  I'm really puzzled why Microsoft went this route. Binding to Angle property enables some pretty cool scenarios.
  Decisions like this really baffle me, though besides from this and a couple of other minor quibbles, I really love Silverlight.

• I came across a question on the Silverlight Toolkit support forum yesterday asking how to animate the

• I try it like you,but ,my DataBinding have a question just becouse I use another way.
  RotationX="{Binding ElementName=SliderX,path=Value}"
  and it does not work, can you help me?

• PlaneProjection doesn't derive from FrameworkElement, so you must write the XAML the way I did.

• Ah Winston - he may have been a drunkard and a dope but he had a way with the language few can grasp :-)

• There is a bug in this ElementName binding. If you are trying to bind to a dependency property on the usercontrol and you provide a name for the usercontrol so you can bind to it, the name is over-written by the parent control if they give it a name. This makes it impossible to know what the name of the usercontrol is to bind to.
  Take for example I'm building a DateTimePicker (pretty sad I have to build my own). I have a texbox inside the DateTimePicker usercontrol that I want to bind the the dependency property Value on the control. So I give my control a name of myUC and use that in binding to the property Value.
  Now somebody comes along and uses two instances of my DateTimePicker control, naming each differently. Now my binding doesn't work :`(

• I ended up doing the following....don't know if it's the best idea but it seems to work.
  using System;
  using System.Windows;
  using System.Windows.Controls;
  using System.ComponentModel;
  namespace TimeInputControl
  {
  public class data: INotifyPropertyChanged
  {
  private DateTime _DateValue;
  public DateTime DateValue
  {
  get { return _DateValue; }
  set { _DateValue = value; if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("DateValue"));}
  }
  #region INotifyPropertyChanged Members
  public event PropertyChangedEventHandler PropertyChanged;
  #endregion
  }
  public partial class DateTimePicker : UserControl
  {
  private data dc = new data();
  public DateTimePicker()
  {
  InitializeComponent();
  this.DataContext = dc;
  }
  public DateTime Value
  {
  get { return (DateTime)GetValue(ValueProperty); }
  set { SetValue(ValueProperty, value); dc.DateValue = value; }
  }
  // Using a DependencyProperty as the backing store for Value. This enables animation, styling, binding, etc...
  public static readonly DependencyProperty ValueProperty =
  DependencyProperty.Register("Value", typeof(DateTime), typeof(DateTimePicker), new PropertyMetadata(System.DateTime.Now));
  }
  }

• Earler this year, I wrote about Silverlight 3's new element data binding feature , which enables XAML

• Saved my life!! I've been trying to solve this for 2 days...