如何:向绘图应用 GuidelineSet

此示例演示如何将 GuidelineSet 应用于 DrawingGroup

DrawingGroup 类是唯一具有 GuidelineSet 属性的 Drawing 类型。 要将 GuidelineSet 应用到另一种类型的 Drawing,请将其添加到 DrawingGroup,然后将 GuidelineSet 应用到你的 DrawingGroup

示例

下面的示例创建了两个几乎相同的 DrawingGroup 对象;唯一的区别是:第二个 DrawingGroup 有一个 GuidelineSet,而第一个没有。

下图显示该示例的输出。 由于这两个 DrawingGroup 对象之间的绘制差异非常细微,因此放大了部分绘图。

A DrawingGroup with and without a GuidelineSet

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace SDKSample
{
    /// <summary>
    /// This example shows how to apply a GuidelineSet to
    /// a drawing.
    /// </summary>
    public class DrawingGroupGuidelineSetExample : Page
    {
        public DrawingGroupGuidelineSetExample()
        {

            //
            // Create a DrawingGroup
            // that has no guideline set
            //
            GeometryDrawing drawing1 = new GeometryDrawing(
                    Brushes.Black,
                    null,
                    new RectangleGeometry(new Rect(0,20,30,80))
                );

            GeometryGroup whiteRectangles = new GeometryGroup();
            whiteRectangles.Children.Add(new RectangleGeometry(new Rect(5.5, 25, 20, 20)));
            whiteRectangles.Children.Add(new RectangleGeometry(new Rect(5.5, 50, 20, 20)));
            whiteRectangles.Children.Add(new RectangleGeometry(new Rect(5.5, 75, 20, 20)));

            GeometryDrawing drawing2 = new GeometryDrawing(
                    Brushes.White,
                    null,
                    whiteRectangles
                );

            // Create a DrawingGroup
            DrawingGroup drawingGroupWithoutGuidelines = new DrawingGroup();
            drawingGroupWithoutGuidelines.Children.Add(drawing1);
            drawingGroupWithoutGuidelines.Children.Add(drawing2);

            // Use an Image control and a DrawingImage to
            // display the drawing.
            DrawingImage drawingImage01 = new DrawingImage(drawingGroupWithoutGuidelines);

            // Freeze the DrawingImage for performance benefits.
            drawingImage01.Freeze();

            Image image01 = new Image();
            image01.Source = drawingImage01;
            image01.Stretch = Stretch.None;
            image01.HorizontalAlignment = HorizontalAlignment.Left;
            image01.Margin = new Thickness(10);

            //
            // Create another DrawingGroup and apply
            // a blur effect to it.
            //

            // Create a clone of the first DrawingGroup.
            DrawingGroup drawingGroupWithGuidelines =
                drawingGroupWithoutGuidelines.Clone();

            // Create a guideline set.
            GuidelineSet guidelines = new GuidelineSet();
            guidelines.GuidelinesX.Add(5.5);
            guidelines.GuidelinesX.Add(25.5);
            guidelines.GuidelinesY.Add(25);
            guidelines.GuidelinesY.Add(50);
            guidelines.GuidelinesY.Add(75);

            // Apply it to the drawing group.
            drawingGroupWithGuidelines.GuidelineSet = guidelines;

            // Use another Image control and DrawingImage
            // to display the drawing.
            DrawingImage drawingImage02 = new DrawingImage(drawingGroupWithGuidelines);

            // Freeze the DrawingImage for performance benefits.
            drawingImage02.Freeze();

            Image image02 = new Image();
            image02.Source = drawingImage02;
            image02.Stretch = Stretch.None;
            image02.HorizontalAlignment = HorizontalAlignment.Left;
            image02.Margin = new Thickness(50, 10, 10, 10);

            StackPanel mainPanel = new StackPanel();
            mainPanel.Orientation = Orientation.Horizontal;
            mainPanel.HorizontalAlignment = HorizontalAlignment.Left;
            mainPanel.Margin = new Thickness(20);
            mainPanel.Children.Add(image01);
            mainPanel.Children.Add(image02);

            //
            // Use a DrawingBrush to create a grid background.
            //
            GeometryDrawing backgroundRectangleDrawing =
                new GeometryDrawing(
                    Brushes.White,
                    null,
                    new RectangleGeometry(new Rect(0,0,1,1))
                );
            PolyLineSegment backgroundLine1 = new PolyLineSegment();
            backgroundLine1.Points.Add(new Point(1, 0));
            backgroundLine1.Points.Add(new Point(1, 0.1));
            backgroundLine1.Points.Add(new Point(0, 0.1));
            PathFigure line1Figure = new PathFigure();
            line1Figure.Segments.Add(backgroundLine1);
            PathGeometry backgroundLine1Geometry = new PathGeometry();
            backgroundLine1Geometry.Figures.Add(line1Figure);
            GeometryDrawing backgroundLineDrawing1 = new GeometryDrawing(
                    new SolidColorBrush(Color.FromArgb(255,204,204,255)),
                    null,
                    backgroundLine1Geometry
                );
            PolyLineSegment backgroundLine2 = new PolyLineSegment();
            backgroundLine2.Points.Add(new Point(0, 1));
            backgroundLine2.Points.Add(new Point(0.1, 1));
            backgroundLine2.Points.Add(new Point(0.1, 0));
            PathFigure line2Figure = new PathFigure();
            line2Figure.Segments.Add(backgroundLine2);
            PathGeometry backgroundLine2Geometry = new PathGeometry();
            backgroundLine2Geometry.Figures.Add(line2Figure);
            GeometryDrawing backgroundLineDrawing2 = new GeometryDrawing(
                    new SolidColorBrush(Color.FromArgb(255, 204, 204, 255)),
                    null,
                    backgroundLine2Geometry
                );

            DrawingGroup backgroundGroup = new DrawingGroup();
            backgroundGroup.Children.Add(backgroundRectangleDrawing);
            backgroundGroup.Children.Add(backgroundLineDrawing1);
            backgroundGroup.Children.Add(backgroundLineDrawing2);

            DrawingBrush gridPatternBrush = new DrawingBrush(backgroundGroup);
            gridPatternBrush.Viewport = new Rect(0, 0, 10, 10);
            gridPatternBrush.ViewportUnits = BrushMappingMode.Absolute;
            gridPatternBrush.TileMode = TileMode.Tile;
            gridPatternBrush.Freeze();

            Border mainBorder = new Border();
            mainBorder.Background = gridPatternBrush;
            mainBorder.BorderThickness = new Thickness(1);
            mainBorder.BorderBrush = Brushes.Gray;
            mainBorder.HorizontalAlignment = HorizontalAlignment.Left;
            mainBorder.VerticalAlignment = VerticalAlignment.Top;
            mainBorder.Margin = new Thickness(20);
            mainBorder.Child = mainPanel;

            //
            // Add the items to the page.
            //
            this.Content = mainBorder;
            this.Background = Brushes.White;
        }
    }
}
<Page 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:PresentationOptions="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" 
  xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
  mc:Ignorable="PresentationOptions">
  <Border BorderThickness="1" BorderBrush="Gray" 
    HorizontalAlignment="Left" VerticalAlignment="Top"
    Margin="20">
    <StackPanel Margin="20" Orientation="Horizontal">


        <Image Stretch="None" Margin="10">
          <Image.Source>
            <DrawingImage PresentationOptions:Freeze="True">
              <DrawingImage.Drawing>

                <!-- This DrawingGroup has no GuidelineSet. -->
                <DrawingGroup>
                  <GeometryDrawing Brush="Black">
                    <GeometryDrawing.Geometry>
                      <RectangleGeometry Rect="0,20,30,80" />
                    </GeometryDrawing.Geometry>
                  </GeometryDrawing>
                  <GeometryDrawing Brush="White">
                    <GeometryDrawing.Geometry>
                      <GeometryGroup>
                        <RectangleGeometry Rect="5.5,25, 20,20" />
                        <RectangleGeometry Rect="5.5,50, 20,20" />
                        <RectangleGeometry Rect="5.5,75, 20,20" />
                      </GeometryGroup>
                    </GeometryDrawing.Geometry>
                  </GeometryDrawing>
                </DrawingGroup>
              </DrawingImage.Drawing>
            </DrawingImage>
          </Image.Source>
        </Image>

        <Image Stretch="None" Margin="50,10,10,10">
          <Image.Source>
            <DrawingImage PresentationOptions:Freeze="True">
              <DrawingImage.Drawing>

                <!-- This DrawingGroup has a GuidelineSet. -->
                <DrawingGroup>
                  <GeometryDrawing Brush="Black">
                    <GeometryDrawing.Geometry>
                      <RectangleGeometry Rect="0,20,30,80" />
                    </GeometryDrawing.Geometry>
                  </GeometryDrawing>
                  <GeometryDrawing Brush="White">
                    <GeometryDrawing.Geometry>
                      <GeometryGroup>
                        <RectangleGeometry Rect="5.5,25, 20,20" />
                        <RectangleGeometry Rect="5.5,50, 20,20" />
                        <RectangleGeometry Rect="5.5,75, 20,20" />
                      </GeometryGroup>
                    </GeometryDrawing.Geometry>
                  </GeometryDrawing>
                  <DrawingGroup.GuidelineSet>

                    <!-- The GuidelineSet -->
                    <GuidelineSet
                      GuidelinesX="5.5,25.5" GuidelinesY="25,50,75" />
                  </DrawingGroup.GuidelineSet>
                </DrawingGroup>
              </DrawingImage.Drawing>
            </DrawingImage>
          </Image.Source>
        </Image>
    </StackPanel>

    <Border.Background>
      <DrawingBrush  Viewport="0,0,10,10" ViewportUnits="Absolute" TileMode="Tile"
        PresentationOptions:Freeze="True">
        <DrawingBrush.Drawing>
          <DrawingGroup>
            <GeometryDrawing Brush="White">
              <GeometryDrawing.Geometry>
                <RectangleGeometry Rect="0,0,1,1" />
              </GeometryDrawing.Geometry>
            </GeometryDrawing>
            <GeometryDrawing Geometry="M0,0 L1,0 1,0.1, 0,0.1Z " Brush="#CCCCFF" />
            <GeometryDrawing Geometry="M0,0 L0,1 0.1,1, 0.1,0Z" Brush="#CCCCFF" />
          </DrawingGroup>
        </DrawingBrush.Drawing>
      </DrawingBrush>    
    </Border.Background>
  </Border>
</Page>

另请参阅