与EllipseGeometry结合LineGeometry(在代码,而不是XAML)(Combin

2019-09-02 03:58发布

我试图创建一个WPF自定形状。 对于初学者来说,我只是想创建一个简单的线,即两端各有一个圆(我知道有LineCaps,但是这不是我要找的)。

我已经研究过一些教程,并做了最简单的方式,似乎用一个CombinedGeometry 。 不过,我不能让它正常工作。 这里是我的代码创建几何对象:

protected override Geometry DefiningGeometry
    {
        get
        {
            Point ellipseCenter1 = new Point(X1 - this.CapDiameter / 2, Y1 - this.CapDiameter / 2);
            Point ellipseCenter2 = new Point(X2 - this.CapDiameter / 2, Y2 - this.CapDiameter / 2);
            var ellipse1 = new EllipseGeometry(ellipseCenter1, CapDiameter, CapDiameter);
            var ellipse2 = new EllipseGeometry(ellipseCenter2, CapDiameter, CapDiameter);
            var line = new LineGeometry(this.StartPoint, this.EndPoint);

            var combined1 = new CombinedGeometry(GeometryCombineMode.Union, ellipse1, line);
            var combined2 = new CombinedGeometry(GeometryCombineMode.Union, combined1, ellipse2);

            // Freeze the geometry for performance benefits
            combined2.Freeze();

            return combined2;
        }
    }

然而,出于某种原因,这并不划清界线。 它利用两个圆,但也不行。 很显然,我在这里失去了一些东西,可能有人指出什么? :)

就在如此重要的情况下,这里是班里的其他:

#region Dependency Properties
public static readonly DependencyProperty X1Property = 
    DependencyProperty.Register(
        "X1", 
        typeof(double),
        typeof(CappedLine), 
        new FrameworkPropertyMetadata(
                0.0, 
                FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.AffectsMeasure
            )
    );
public static readonly DependencyProperty Y1Property =
    DependencyProperty.Register(
        "Y1",
        typeof(double),
        typeof(CappedLine),
        new FrameworkPropertyMetadata(
                0.0,
                FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.AffectsMeasure
            )
    );
public static readonly DependencyProperty X2Property =
    DependencyProperty.Register(
        "X2",
        typeof(double),
        typeof(CappedLine),
        new FrameworkPropertyMetadata(
                0.0,
                FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.AffectsMeasure
            )
    );
public static readonly DependencyProperty Y2Property =
    DependencyProperty.Register(
        "Y2",
        typeof(double),
        typeof(CappedLine),
        new FrameworkPropertyMetadata(
                0.0,
                FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.AffectsMeasure
            )
    );
public static readonly DependencyProperty CapDiameterProperty =
    DependencyProperty.Register(
        "CapDiameter",
        typeof(double),
        typeof(CappedLine),
        new FrameworkPropertyMetadata(
                0.0,
                FrameworkPropertyMetadataOptions.AffectsRender | FrameworkPropertyMetadataOptions.AffectsMeasure
            )
    );

#endregion
#region CLR Properties

public double X1
{
    get { return (double)base.GetValue(X1Property); }
    set { base.SetValue(X1Property, value); }
}

public double Y1
{
    get { return (double)base.GetValue(Y1Property); }
    set { base.SetValue(Y1Property, value); }
}

public double X2
{
    get { return (double)base.GetValue(X2Property); }
    set { base.SetValue(X2Property, value); }
}

public double Y2
{
    get { return (double)base.GetValue(Y2Property); }
    set { base.SetValue(Y2Property, value); }
}

public Point StartPoint
{
    get { return (new Point(X1, Y1)); }
}

public Point EndPoint
{
    get { return (new Point(X2, Y2)); }
}

public double CapDiameter
{
    get { return (double)base.GetValue(CapDiameterProperty); }
    set { base.SetValue(CapDiameterProperty, value); }
}

#endregion

这里是XAML我用来测试它的代码:

<Window x:Class="HG.WPF.Shapes.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:shapes="clr-namespace:Tomers.WPF.Shapes"

    Title="WPF Custom Shapes" Height="300" Width="300" ResizeMode="NoResize">

    <Canvas Background="Black">
        <shapes:CappedLine X1="30" Y1="30" X2="200" Y2="200" CapDiameter="5" Fill="White" Stroke="White" StrokeThickness="2"></shapes:CappedLine>        
    </Canvas>

</Window>

Answer 1:

LineGeometry如果尝试的对象将会消失Union他们。 从MSDN:

该GeometryCombineMode属性指定的两个几何将如何组合。 需要注意的是CombinedGeometry通过结合两个几何图形指定的区域,所以不具有区域(如LineGeometry)合并时消失的几何形状。

您可以使用GeometryGroup

GeometryGroup combined = new GeometryGroup();
combined.Children.Add(ellipse1);
combined.Children.Add(ellipse2);
combined.Children.Add(line);

或者可以使用CombinedGeometry椭圆上的对象一起使用的线,然后再组GeometryGroup



文章来源: Combining LineGeometry with EllipseGeometry (in code, not XAML)