在WPF形狀中添加一些文本

Question

我有一個自定義的WPF控件MyLine，它應該在中間代表一些文本。

public class MyLine : Shape 
{ 
    public double X1, Y1, X2, Y2; 
    public bool IsTextDisplayed; 
    public string Caption; 

    protected override System.Windows.Media.Geometry DefiningGeometry 
    { 
     get 
     { 
      var geometryGroup = new GeometryGroup(); 

      if (IsTextDisplayed) 
      { 
       // calculate text point 
       var midPoint = new Point((X1 + X2)/2.0, (Y1 + Y2)/2.0); 
       // add 'Caption' text in that point 
       // ??? 
      } 

      // Add line 
      geometryGroup.Children.Add(new LineGeometry(
       new Point(X1, Y1), new Point(X2, Y2))); 

      return geometryGroup; 

     } 
    } 
} 

那麼，我應該如何在這裏添加文本？

Answer 1

創建FormattedText對象，然後從它創建一個幾何：

FormattedText ft = new FormattedText(
    "Caption", 
    Thread.CurrentThread.CurrentCulture, 
    System.Windows.FlowDirection.LeftToRight, 
    new Typeface("Verdana"), 32, Brushes.Black); 

Geometry geometry = ft.BuildGeometry(midpoint); 

geometryGroup.Children.Add(geometry);