Tip: How to declare a dependency property in Silverlight?

Below is an example.

The default value and the propertychanged handler are optional. Depends on whether you want something besides null as the default value if the setter is never called, and whether you want to execute some code when the value changes. Note that the naming of properties are important. Search/Replace "MyProperty" with whatever you want to call it, but not that the stafic DP must be names [name]Property.

public MyObjectType MyProperty
{
	get { return (MyObjectType)GetValue(MyPropertyProperty); }
	set { SetValue(MyPropertyProperty, value); } //Never put code here! Put it in onMyPropertyChanged
}

public static readonly DependencyProperty MyPropertyProperty =
	DependencyProperty.Register("MyProperty", typeof(MyObjectType), typeof(MyControl), new PropertyMetadata([DefaultValue], onMyPropertyChanged));

private static void onMyPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
	MyControl obj = d as MyControl;
	//handle changed values
}

Next step is to create a Control with a Template. You can then bind this value into your control using:

<TextBox Text="{TemplateBinding MyProperty}" /> 

You might want to see this post on how to create your own custom controls: http://www.silverlightshow.net/items/Creating-a-Silverlight-Custom-Control-The-Basics.aspx