How to redraw or refresh in OnRender?

Question

I want to draw something dynamically. Following code shows my OnRender. I\'m setting DrawItem somewhere in my program where I need it. But when I\'m calling DrawItem =

Answer 1

I ran into similar issue and found an even more elegant solution. Define a DependencyProperty like so:

public static readonly DependencyProperty PropertyNameProperty = DependencyProperty.Register("PropertyName", typeof(PropertyType), typeof(PropertyElementType), new FrameworkPropertyMetadata(DefaultPropertyValue, FrameworkPropertyMetadataOptions.AffectsRender));

The key here is this:

FrameworkPropertyMetadataOptions.AffectsRender

So now the property can be set in XAML and updates visual automatically on changing.