EDIT:
This line,
<props:Resources x:Key="Resources"/>
is a bad approach to accesing the Project.Properties.Resources namespace. It causes awkward glitches when recompiling.
Much better to use x:Static to do somthing like this,
Text="{x:Static props:Resources.SomeText}"
in your binding. Thx to Ben
Okay, this is how I did it. It's not perfect but it works.
Remember, there is a project resource called FormattedText.
cs:
// TextBlock with a bindable InlineCollection property.
// Type is List(Inline) not InlineCollection becuase
// InlineCollection makes the IDE xaml parser complain
// presumably this is caused by an inherited attribute.
public class BindableTextBlock : TextBlock
{
public static readonly DependencyProperty InlineCollectionProperty =
DependencyProperty.Register(
"InlineCollection",
typeof(List<Inline>),
typeof(BindableTextBlock),
new UIPropertyMetadata(OnInlineCollectionChanged));
private static void OnInlineCollectionChanged(DependencyObject sender,
DependencyPropertyChangedEventArgs e)
{
BinableTextBlock instance = sender as BindableTextBlock;
if (instance != null)
{
List<Inline> newText = e.NewValue as List<Inline>;
if (newText != null)
{
// Clear the underlying Inlines property
instance.Inlines.Clear();
// Add the passed List<Inline> to the real Inlines
instance.Inlines.AddRange(newText.ToList());
}
}
}
public List<Inline> InlineCollection
{
get
{
return (List<Inline>)GetValue(InlineCollectionProperty);
}
set
{
SetValue(InlineCollectionProperty, value);
}
}
}
// Convertor between a string of xaml with implied run elements
// and a generic list of inlines
[ValueConversion(typeof(string), typeof(List<Inline>))]
public class StringInlineCollectionConvertor : IValueConverter
{
public object Convert(object value,
Type targetType,
object parameter,
System.Globalization.CultureInfo culture)
{
string text = value as String;
// a surrogate TextBlock to host an InlineCollection
TextBlock results = new TextBlock();
if (!String.IsNullOrEmpty(text))
{
//Arbritary literal acting as a replace token,
//must not exist in the empty xaml definition.
const string Replace = "xxx";
// add a dummy run element and replace it with the text
results.Inlines.Add(new Run(Replace));
string resultsXaml = XamlWriter.Save(results);
string resultsXamlWithText = resultsXaml.Replace(Replace, text);
// deserialise the xaml back into our TextBlock
results = XamlReader.Parse(resultsXamlWithText) as TextBlock;
}
return results.Inlines.ToList<Inline>();
}
// Not clear when this will be called but included for completeness
public object ConvertBack(
object value,
Type targetType,
object parameter,
System.Globalization.CultureInfo culture)
{
String results = String.Empty;
InlineCollection inlines = value as InlineCollection;
if (inlines != null)
{
//read the xaml as xml and return the "content"
var reader =
XElement.Parse(XamlWriter.Save(inlines)).CreateReader();
reader.MoveToContent();
results = reader.ReadInnerXml();
}
return results;
}
}
xaml:
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:props="clr-namespace:Project.Properties"
xmlns:local="clr-namespace:Project">
<Window.Resources>
<props:Resources x:Key="Resources"/>
<local:StringInlineCollectionConvertor x:Key="InlineConvert"/>
</Window.Resources>
<local:BindableTextBlock InlineCollection="
{Binding Source={StaticResource Resources},
Path=FormattedText,
Converter={StaticResource InlineConvert}}"/>
</Window>
I made 2 classes. A sub-classed TextBlock with a "bindable" InlineCollection and an IValueConverter to convert the collection from and to a String.
Using InlineCollection directly as the type of the property made VS2010 complain, although the code still ran fine. I changed to a generic list of Inlines. I assume that there is an inherited attribute telling VS that the InlineCollection has no constructor.
I tryed making the InlineCollection property the BindableTextBlock's ContentProperty but ran into issues and out of time. Please feel free to take the next step and tell me about it.
I apologise for any errata but this code had to be transcribed and sanitised.
If there is a better way of doing this, surely there must be, please tell me that too. Wouldn't it be nice if this functionality was built in or, have I missed something?
