Binding to a custom dependency property

When the source's "MyColor" property is changed, the GraphPanel's "AxisColor"
is not changed.

This binding works fine if I use one of GraphPanel's built-in dependency
properties, such as Tag.

-----------------------------------------------

public class MySource : INotifyPropertyChanged
{
....
public SolidColorBrush MyColor {...}
....
}

-----------------------------------------------

<Grid> <!-- DataContext set in code to MySource -->
....
<GraphPanel : DockPanel>
<Binding Path="MyColor">
</GraphPanel>
....
</Grid>

------------------------------------------------

public class GraphPanel
{
....
public static readonly DependencyProperty AxisColorProperty =
DependencyProperty.Register(
"AxisColor",
typeof(SolidColorBrush),
typeof(GraphPanel),
new PropertyMetadata(Brushes.Black));

public SolidColorBrush AxisColor
{
get { return (SolidColorBrush)this.GetValue(AxisColorProperty); }
set { this.SetValue(AxisColorProperty, value); }
}
....
}

I found the following at
http://www.quepublishing.com/article...seqNum=2&rl=1:


WARNING: .NET property wrappers are bypassed at run-time when setting
dependency properties in XAML!

Although the XAML compiler depends on the property wrapper at compile-time,
at run-time WPF calls the underlying GetValue and SetValue methods directly!
Therefore, to maintain parity between setting a property in XAML and
procedural code, it's crucial that property wrappers do not contain any logic
in addition to the GetValue/SetValue calls. If you want to add custom logic,
that's what the registered callbacks are for. All of WPF's built-in property
wrappers abide by this rule, so this warning is for anyone writing a custom
class with its own dependency properties.



"diffeq" wrote:

> When the source's "MyColor" property is changed, the GraphPanel's "AxisColor"
> is not changed.
>
> This binding works fine if I use one of GraphPanel's built-in dependency
> properties, such as Tag.
>
> -----------------------------------------------
>
> public class MySource : INotifyPropertyChanged
> {
> ...
> public SolidColorBrush MyColor {...}
> ...
> }
>
> -----------------------------------------------
>
> <Grid> <!-- DataContext set in code to MySource -->
> ...
> <GraphPanel : DockPanel>
> <Binding Path="MyColor">
> </GraphPanel>
> ...
> </Grid>
>
> ------------------------------------------------
>
> public class GraphPanel
> {
> ...
> public static readonly DependencyProperty AxisColorProperty =
> DependencyProperty.Register(
> "AxisColor",
> typeof(SolidColorBrush),
> typeof(GraphPanel),
> new PropertyMetadata(Brushes.Black));
>
> public SolidColorBrush AxisColor
> {
> get { return (SolidColorBrush)this.GetValue(AxisColorProperty); }
> set { this.SetValue(AxisColorProperty, value); }
> }
> ...
> }