How to set a dependency property from InLine event of a textblock? - wpf

Question

I'm trying to set the dependency property "WordPad" from within the Inline event of MouseEnter from a CustomTextBlock. But this error results:
An object reference is required for the non-static field, method, or property 'WpfCustomControlLibrary.CustomTextBlock.WordPad.get'
How can I achieve this?
Any help would be most appreciated. Thanks.
Given the following class:
public class CustomTextBlock : TextBlock
{
public string InLineText
{
get { return (string)GetValue(InLineTextProperty); }
set { SetValue(InLineTextProperty, value); }
}
public static readonly DependencyProperty InLineTextProperty =
DependencyProperty.Register("InLineText", typeof(string), typeof(CustomTextBlock),
new FrameworkPropertyMetadata(string.Empty,
FrameworkPropertyMetadataOptions.AffectsMeasure,
(o, e) =>
{
//PropertyChangedCallback
CustomTextBlock tb = (CustomTextBlock)o;
string text = (string)e.NewValue;
tb.Inlines.Clear();
if (String.IsNullOrEmpty(text))
return;
List<Inline> inlines = new List<Inline>();
string[] words = Regex.Split(text, #"(\s+)");
Inline inline = null;
foreach (string s in words)
{
Run run = new Run(s);
inline = run;
inline.MouseEnter += new System.Windows.Input.MouseEventHandler(inline_MouseEnter);
inline.MouseLeave += new System.Windows.Input.MouseEventHandler(inline_MouseLeave);
tb.Inlines.Add(inline);
}
}));
public WritingPad WordPad
{
get { return (WritingPad)GetValue(WordPadProperty); }
set { SetValue(WordPadProperty, value); }
}
public static readonly DependencyProperty WordPadProperty =
DependencyProperty.Register("WordPad", typeof(WritingPad), typeof(CustomTextBlock), new UIPropertyMetadata(null));
static void inline_MouseEnter(object sender, System.Windows.Input.MouseEventArgs e)
{
Run Sender = sender as Run;
TextPointer tp0 = Sender.ContentStart;
TextPointer tp1 = Sender.ContentEnd;
Rect StartRect = tp0.GetCharacterRect(LogicalDirection.Forward);
Rect EndRect = tp1.GetCharacterRect(LogicalDirection.Backward);
StartRect.Union(EndRect);
WordPad = new WritingPad(); <--**THIS FAILS ????
}

Answer 1

Make the inline_MouseEnter and inline_MouseLeave methods non-static and attach them to your Runs like this:
inline.MouseEnter += tb.inline_MouseEnter;
inline.MouseLeave += tb.inline_MouseLeave;
Even better would be to make the whole PropertyChangedCallback non-static and then write the dependency property declaration like this:
public static readonly DependencyProperty InLineTextProperty =
DependencyProperty.Register("InLineText", typeof(string), typeof(CustomTextBlock),
new FrameworkPropertyMetadata(string.Empty,
FrameworkPropertyMetadataOptions.AffectsMeasure,
(o, e) => ((CustomTextBlock)o).InlineTextChanged((string)e.NewValue)));
private void InlineTextChanged(string text)
{
Inlines.Clear();
if (!string.IsNullOrEmpty(text))
{
foreach (string s in Regex.Split(text, #"(\s+)"))
{
var run = new Run(s);
run.MouseEnter += inline_MouseEnter;
run.MouseLeave += inline_MouseLeave;
Inlines.Add(run);
}
}
}

Answer 2

I'm hopeful a guru can give a better solution.
It should be noted that Run has a "Parent" property which resolved to this instance of CustomTextBlock. Hence, this seems to work,
CustomTextBlock ctb = Sender.Parent as CustomTextBlock;
ctb.WordPad = new WritingPad
{
WordBounds = StartRect,
WritingPadMode = Enumerations.WritingPadModes.EditingByWord
};