Bind dependency Property to Child Element in Code behind - wpf

Question

I basically got a ContentControl that has Border as content witch also has TextBlock as content. What i want is that e.g. the Foreground Brush of the TextBlock is bound to a dependency property of the parent ContentControl... I am stuck right here i don't know how to solve this.
public class NumberRollItem : ContentControl
{
public int Index { get; set; }
public int AnimationIndex { get; set; }
public Brush ItemForeground
{
get { return (Brush)GetValue(ItemForegroundProperty); }
set { SetValue(ItemForegroundProperty, value); }
}
public static readonly DependencyProperty ItemForegroundProperty =
DependencyProperty.Register("ItemForeground", typeof(Brush), typeof(NumberRollItem), new PropertyMetadata(new SolidColorBrush(Colors.White)));
public Brush ItemBackground
{
get { return (Brush)GetValue(ItemBackgroundProperty); }
set { SetValue(ItemBackgroundProperty, value); }
}
public static readonly DependencyProperty ItemBackgroundProperty =
DependencyProperty.Register("ItemBackground", typeof(Brush), typeof(NumberRollItem), new PropertyMetadata(new SolidColorBrush(Colors.Black)));
public double ItemFontSize
{
get { return (double)GetValue(ItemFontSizeProperty); }
set { SetValue(ItemFontSizeProperty, value); }
}
public static readonly DependencyProperty ItemFontSizeProperty =
DependencyProperty.Register("ItemFontSize", typeof(double), typeof(NumberRollItem), new PropertyMetadata(45d));
public NumberRollItem(char c, int index)
{
this.Index = index;
string text = ""; text += c;
HorizontalContentAlignment = System.Windows.HorizontalAlignment.Stretch;
Content = new Border()
{
Background = ItemBackground, // Background bound to ItemBackground but how??
HorizontalAlignment = System.Windows.HorizontalAlignment.Stretch,
VerticalAlignment = System.Windows.VerticalAlignment.Stretch,
Child = new TextBlock()
{
FontSize = 45,
Text = text,
Foreground = ItemForeground,
},
};
}
}

Answer 1

Updated for WP
Well if you're doing everything via code, you can create the Binding in code too,
Something like:
public NumberRollItem(char c, int index)
{
this.Index = index;
string text = ""; text += c;
// Giving This control a Name to later use for Binding
string thisControlName = "NumberItem";
Name = thisControlName;
HorizontalContentAlignment = System.Windows.HorizontalAlignment.Stretch;
var tBlock = new TextBlock()
{
FontSize = 45,
Text = text
};
var binding = new Binding
{
ElementName = thisControlName,
Path = new PropertyPath("ItemForeground")
};
tBlock.SetBinding(TextBlock.ForegroundProperty, binding);
Content = new Border()
{
Background = ItemBackground,
HorizontalAlignment = System.Windows.HorizontalAlignment.Stretch,
VerticalAlignment = System.Windows.VerticalAlignment.Stretch,
Child = tBlock,
};
}
What you're doing with this code is:
In the constructor of NumberRollItem you create a Binding with ElementName pointing to NumberRollItem class and assign the Binding to the TextBlock.ForegroundProperty. This will thus have them bound to allow for any future changes to ItemForeground to affect the TextBlock.Foreground as well.
Not sure why you've taken this approach and not the xaml Style route but whatever works for ya :)