Is there any xaml serialization attribute that I can specify for a dependency property which actually is a collection (TextDecorationCollection)?
I want to use serialization for cloning a very large and complex object. Here a sample of the code, simplified:
There is a MyVisualObject, that contains a lot of properties, including a custom font, which I want to clone
[AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]
public class Export : Attribute
{
}
public class MyVisualObject : DependencyObject
{
[Export]
public CustomFont Font
{
get { return (CustomFont)GetValue(FontProperty); }
set { SetValue(FontProperty, value); }
}
// Using a DependencyProperty as the backing store for Font. This enables animation, styling, binding, etc...
public static readonly DependencyProperty FontProperty =
DependencyProperty.Register("Font", typeof(CustomFont), typeof(MyVisualObject));
public MyVisualObject()
{
this.Font = new CustomFont();
}
}
And the custom font is defined like this:
public class CustomFont : DependencyObject
{
public TextDecorationCollection Decorations
{
get { return (TextDecorationCollection)GetValue(DecorationsProperty); }
set { SetValue(DecorationsProperty, value); }
}
// Using a DependencyProperty as the backing store for TextDecorations. This enables animation, styling, binding, etc...
public static readonly DependencyProperty DecorationsProperty =
DependencyProperty.Register("Decorations", typeof(TextDecorationCollection), typeof(CustomFont), new UIPropertyMetadata(new TextDecorationCollection()));
public CustomFont()
{
this.Decorations = System.Windows.TextDecorations.Underline;
}
}
THe deep clone method:
public static T DeepClone<T>(T from)
{
object clone = Activator.CreateInstance(from.GetType());
Type t = from.GetType();
System.Reflection.PropertyInfo[] pinf = t.GetProperties();
foreach (PropertyInfo p in pinf)
{
bool serialize = false;
foreach (object temp in p.GetCustomAttributes(true))
{
if (temp is Export)
{
serialize = true;
}
}
if (serialize)
{
string xaml = XamlWriter.Save(p.GetValue(from, null));
XmlReader rd = XmlReader.Create(new StringReader(xaml));
p.SetValue(clone, XamlReader.Load(rd), null);
}
}
return (T)clone;
}
The problem is that each time I initialize the Decorations as Underline
this.Decorations = System.Windows.TextDecorations.Underline;
the cloning process crashes with this error:'Add value to collection of type 'System.Windows.TextDecorationCollection' threw an exception.' Line number '1' and line position '213'.
As far as I found out, the serialization, which is this part
string xaml = XamlWriter.Save(p.GetValue(from, null));
returns an xaml which does not have the decorations set as a collection:
<CustomFont xmlns="clr-namespace:WpfApplication1;assembly=WpfApplication1" xmlns:av="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<CustomFont.Decorations>
<av:TextDecoration Location="Underline" />
</CustomFont.Decorations>
</CustomFont>
But the clone process would work if the xaml would be like this:
<CustomFont xmlns="clr-namespace:WpfApplication1;assembly=WpfApplication1" xmlns:av="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<CustomFont.Decorations>
<av:TextDecorationCollection>
<av:TextDecoration Location="Underline" />
</av:TextDecorationCollection>
</CustomFont.Decorations>
</CustomFont>
I found a workaround, something with string replacements:
xaml = xaml.Replace("<CustomFont.Decorations><av:TextDecoration Location=\"Underline\" /></CustomFont.Decorations>", "<CustomFont.Decorations><av:TextDecorationCollection><av:TextDecoration Location=\"Underline\" /></av:TextDecorationCollection></CustomFont.Decorations>");
but I think it's really dirty, and I would apreciate it if you could provide a more clean solution (specifying an attribute for the Decorations property for example)
