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在WPF装饰器中绘制虚线

graphics xaml wpf .net c#

flq · 技术社区 · 14 年前

我在网上找到了几篇关于在WPF中绘制虚线的文章。然而,它们似乎是围绕使用line类(wpf中的uielement)而展开的。就像这样:

Line myLine = new Line();
DoubleCollection dashes = new DoubleCollection();
dashes.Add(2);
dashes.Add(2);
myLine.StrokeDashArray = dashes;

现在,我在一个装饰器中,在那里我只能访问绘图上下文。在那里,我或多或少地被简化为绘图原语、画笔、钢笔、几何图形等。这看起来更像:

var pen = new Pen(new SolidColorBrush(Color.FromRgb(200, 10, 20)), 2);
drawingContext.DrawLine(pen, point1, point2);

我被困在如何在这个API级别上做一条虚线。我希望这不是“一条一条地画小线”,而是其他一些我没见过的东西……

2 回复 | 直到 12 年前

Samuel Jack 14 年前

看看 Pen.DashStyle 财产。您可以使用 DashStyles 类,它提供一些预定义的破折号样式,或者您可以通过创建新的破折号和间隙来指定自己的图案。 DashStyle 实例。

var pen = new Pen(new SolidColorBrush(Color.FromRgb(200, 10, 20)), 2);
pen.DashStyle = DashStyles.Dash;
drawingContext.DrawLine(pen, point1, point2);

Lee Louviere 12 年前

你不必拘泥于原语。如果遵循此模式,可以向装饰器添加任何内容。

public class ContainerAdorner : Adorner
{
    // To store and manage the adorner's visual children.
    VisualCollection visualChildren;

    // Override the VisualChildrenCount and GetVisualChild properties to interface with 
    // the adorner's visual collection.
    protected override int VisualChildrenCount { get { return visualChildren.Count; } }
    protected override Visual GetVisualChild(int index) { return visualChildren[index]; }

    // Initialize the ResizingAdorner.
    public ContainerAdorner (UIElement adornedElement)
        : base(adornedElement)
    {
        visualChildren = new VisualCollection(this);
        visualChildren.Add(_Container);
    }
    ContainerClass _Container= new ContainerClass();

    protected override Size ArrangeOverride(Size finalSize)
    {
        // desiredWidth and desiredHeight are the width and height of the element that's being adorned.  
        // These will be used to place the Adorner at the corners of the adorned element.  
        double desiredWidth = AdornedElement.DesiredSize.Width;
        double desiredHeight = AdornedElement.DesiredSize.Height;

        FrameworkElement fe;
        if ((fe = AdornedElement as FrameworkElement) != null)
        {
            desiredWidth = fe.ActualWidth;
            desiredHeight = fe.ActualHeight;
        }

        _Container.Arrange(new Rect(0, 0, desiredWidth, desiredHeight));

        return finalSize;
    }
}