Question

This is similar to my previous question, but that solution did not solve this problem.

fontSizeProperty is not being recognized when I move a method from my Silverlight MainPage code behind (which worked) to a new class in a silverlight library

using System.Windows.Controls;

namespace MyNameSpace
{
    public static class DataGridBuilder
    {
        private static Style BuildHeaderStyle(string tooltip)
        {
            Style newGridHeaderStyle = new Style(typeof(DataGridColumnHeader));
            newGridHeaderStyle.Setters.Add(new Setter { Property = FontSizeProperty, Value = 9.0 });
            newGridHeaderStyle.Setters.Add(new Setter { Property = FontWeightProperty, Value = FontWeights.Bold });
            return newGridHeaderStyle;
        }
    }
}

NOTE: Per MSDN for FontSizeProperty, I do include System.Windows reference, and “using System.Windows.Control”

Based on answers below, I changed “Property = FontSizeProperty” to “Property=DataGridColumnHeader.FontSizeProperty” etc., like this:

    private static Style BuildHeaderStyle(string tooltip)
    {
        FontWeight fw = FontWeights.Bold;
        Style newGridHeaderStyle = new Style(typeof(DataGridColumnHeader));
        newGridHeaderStyle.Setters.Add(new Setter { Property = DataGridColumnHeader.FontSizeProperty, Value = 9.0 });
        newGridHeaderStyle.Setters.Add(new Setter { Property = DataGridColumnHeader.FontWeightProperty, Value = FontWeights.Bold });
        newGridHeaderStyle.Setters.Add(new Setter { Property = DataGridColumnHeader.ContentTemplateProperty, Value = CreateDataGridHeaderTemplate(tooltip) });
        return newGridHeaderStyle;
    }

Answer 1

I believe you want Control.FontSizeProperty and Control.FontWeightProperty instead.

Your MainPage is a user control, which has Control as a superclass and hence inherits the above two dependency properties. Your static class isn’t a subclass of Control so it doesn’t inherit these dependency properties.