Question

我基本上得到了一个ContentControl，它具有Border作为内容，也有TextBlock作为内容。我想要的是，例如TextBlock的Foreground Brush绑定到父ContentControl的依赖属性...我被困在这里我不知道如何解决这个问题。

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

针对WP进行了更新

如果您通过代码执行所有操作，也可以在代码中创建Binding，

类似的东西：

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,
  };
}

您使用此代码执行的操作是：

在NumberRollItem的构造函数中，您创建一个Binding，ElementName指向NumberRollItem类，并将绑定分配给TextBlock.ForegroundProperty。因此，这将限制它们允许ItemForeground的任何未来更改也影响TextBlock.Foreground。

不确定为什么你采用这种方法而不是xaml Style路线，但是对你来说无论如何：）

将依赖属性绑定到代码后面的子元素

1 个答案: