在一个上下文中绘制实线和虚线

Question

我想在一个上下文中画一条虚线和一条实线。但是如果我先画一条虚线，第二条线也是一条虚线。那么如何清理context.setLineDash呢？我试过了context.beginContext()，没用。

代码如下：

if let context = UIGraphicsGetCurrentContext() {
    // The first line
    let startPoint = CGPoint(x: 20, y: rect.height/2)
    let endPoint = CGPoint(x: rect.width - 40, y: rect.height/2)
    context.move(to: startPoint)
    context.addLine(to: endPoint)
    context.setLineWidth(1)
    context.setLineDash(phase: 0, lengths: [4, 4])
    context.setStrokeColor(UIColor.progressDashLineColor.cgColor)
    context.strokePath()
    // Second line
    let startPoint1 = CGPoint(x: 20, y: rect.height/2 + 5)
    let endPoint1 = CGPoint(x: rect.width-120, y: rect.height/2)
    context.setStrokeColor(UIColor.mainColor.cgColor)
    context.setLineWidth(5)
    context.move(to: startPoint1)
    context.addLine(to: endPoint1)
    context.setLineCap(.round)
    context.strokePath()
}

Answer 1

在绘制实线之前将虚线设置为空数组。

context.setLineDash(phase: 0, lengths: [])

来自 CGContext 文档：

Pass an empty array to clear the dash pattern so that all stroke drawing in the context uses solid lines.

Documentation Link

在一个上下文中绘制实线和虚线

Draw solid and dashed line in one context

core-graphics

swift