ios 如何快速制作虚线？
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How to make a dashed line in swift?
提问by A. Steiness
I want to know how to make a dashed line in swift like this: - - - - - - - - instead of a regular straight line like this: ----------------, I know that i can make multiple lines but that will require so much unnecessary code if i can just write it in 1 line. Btw it has to be in CoreGraphics.
我想知道如何像这样快速制作虚线：- - - - - - - - 而不是这样的常规直线：----------------，我知道我可以写多行，但如果我只能写在 1 行中，那将需要很多不必要的代码。顺便说一句，它必须在 CoreGraphics 中。
回答by Fan Jin
Swift 4
斯威夫特 4
@IBOutlet var dashedView: UIView!
func drawDottedLine(start p0: CGPoint, end p1: CGPoint, view: UIView) {
let shapeLayer = CAShapeLayer()
shapeLayer.strokeColor = UIColor.lightGray.cgColor
shapeLayer.lineWidth = 1
shapeLayer.lineDashPattern = [7, 3] // 7 is the length of dash, 3 is length of the gap.
let path = CGMutablePath()
path.addLines(between: [p0, p1])
shapeLayer.path = path
view.layer.addSublayer(shapeLayer)
}
Call function
调用函数
drawDottedLine(start: CGPoint(x: dashedView.bounds.minX, y: dashedView.bounds.minY), end: CGPoint(x: dashedView.bounds.maxX, y: dashedView.bounds.minY), view: dashedView)
With the above you will have a straight line, you can also change points as you wish, for example if you change the end point's y from dashedView.bounds.minYto dashedView.bounds.maxYyou will have diagonal.
有了上面的你将有一条直线，你也可以根据需要改变点，例如，如果你改变终点的 y 从dashedView.bounds.minY到dashedView.bounds.maxY你会有对角线。
If you will use it in a subclass of UIView you won't have the outlet so you will use it with self instead.
如果您将在 UIView 的子类中使用它，您将没有插座，因此您将使用它与 self 代替。
回答by user3230875
You create Dashed Lines the same way as Objective-C, except that you'll use Swift.
您创建虚线的方式与 Objective-C 相同，不同之处在于您将使用 Swift。
Here is how you do it using UIBezierPath:
以下是使用 UIBezierPath 执行此操作的方法：
let path = UIBezierPath()
let p0 = CGPoint(x: self.bounds.minX, y: self.bounds.midY)
path.move(to: p0)
let p1 = CGPoint(x: self.bounds.maxX, y: self.bounds.midY)
path.addLine(to: p1)
let dashes: [ CGFloat ] = [ 16.0, 32.0 ]
path.setLineDash(dashes, count: dashes.count, phase: 0.0)
path.lineWidth = 8.0
path.lineCapStyle = .butt
UIColor.magenta.set()
path.stroke()
Here is how to draw Dotted Lines using UIBezierPath:
下面是如何使用 UIBezierPath 绘制虚线：
let path = UIBezierPath()
let p0 = CGPointMake(CGRectGetMinX(self.bounds), CGRectGetMidY(self.bounds))
path.moveToPoint(p0)
let p1 = CGPointMake(CGRectGetMaxX(self.bounds), CGRectGetMidY(self.bounds))
path.addLineToPoint(p1)
let dashes: [ CGFloat ] = [ 0.0, 16.0 ]
path.setLineDash(dashes, count: dashes.count, phase: 0.0)
path.lineWidth = 8.0
path.lineCapStyle = .Round
UIColor.magentaColor().set()
path.stroke()
Here is how to draw Dashed Lines Using CGContext:
以下是如何使用 CGContext 绘制虚线：
let context: CGContext = UIGraphicsGetCurrentContext()!
let p0 = CGPointMake(CGRectGetMinX(self.bounds), CGRectGetMidY(self.bounds))
CGContextMoveToPoint(context, p0.x, p0.y)
let p1 = CGPointMake(CGRectGetMaxX(self.bounds), CGRectGetMidY(self.bounds))
CGContextAddLineToPoint(context, p1.x, p1.y)
let dashes: [ CGFloat ] = [ 16.0, 32.0 ]
CGContextSetLineDash(context, 0.0, dashes, dashes.count)
CGContextSetLineWidth(context, 8.0)
CGContextSetLineCap(context, .Butt)
UIColor.blueColor().set()
CGContextStrokePath(context)
回答by Amit Kumar
By Using Custom Class inherited from UIView also supports Storyboard.
通过使用从 UIView 继承的自定义类也支持 Storyboard。
All you need to do is make a view in storyboard assign class to that view and see the magic in storyboard.
您需要做的就是在故事板中创建一个视图，将类分配给该视图并查看故事板中的魔力。
@IBDesignable
class DashedLineView : UIView {
@IBInspectable var perDashLength: CGFloat = 2.0
@IBInspectable var spaceBetweenDash: CGFloat = 2.0
@IBInspectable var dashColor: UIColor = UIColor.lightGray
override func draw(_ rect: CGRect) {
super.draw(rect)
let path = UIBezierPath()
if height > width {
let p0 = CGPoint(x: self.bounds.midX, y: self.bounds.minY)
path.move(to: p0)
let p1 = CGPoint(x: self.bounds.midX, y: self.bounds.maxY)
path.addLine(to: p1)
path.lineWidth = width
} else {
let p0 = CGPoint(x: self.bounds.minX, y: self.bounds.midY)
path.move(to: p0)
let p1 = CGPoint(x: self.bounds.maxX, y: self.bounds.midY)
path.addLine(to: p1)
path.lineWidth = height
}
let dashes: [ CGFloat ] = [ perDashLength, spaceBetweenDash ]
path.setLineDash(dashes, count: dashes.count, phase: 0.0)
path.lineCapStyle = .butt
dashColor.set()
path.stroke()
}
private var width : CGFloat {
return self.bounds.width
}
private var height : CGFloat {
return self.bounds.height
}
}
回答by Joshua Hart
Pretty easy UIView Extension for SWIFT 4.2:
SWIFT 4.2非常简单的 UIView 扩展：
extension UIView {
private static let lineDashPattern: [NSNumber] = [2, 2]
private static let lineDashWidth: CGFloat = 1.0
func makeDashedBorderLine() {
let path = CGMutablePath()
let shapeLayer = CAShapeLayer()
shapeLayer.lineWidth = UIView.lineDashWidth
shapeLayer.strokeColor = UIColor.lightGray.cgColor
shapeLayer.lineDashPattern = UIView.lineDashPattern
path.addLines(between: [CGPoint(x: bounds.minX, y: bounds.height/2),
CGPoint(x: bounds.maxX, y: bounds.height/2)])
shapeLayer.path = path
layer.addSublayer(shapeLayer)
}
}
回答by nullforlife
My extension method built from @FanJins answer
我从@FanJins 回答构建的扩展方法
extension UIView {
func createDashedLine(from point1: CGPoint, to point2: CGPoint, color: UIColor, strokeLength: NSNumber, gapLength: NSNumber, width: CGFloat) {
let shapeLayer = CAShapeLayer()
shapeLayer.strokeColor = color.cgColor
shapeLayer.lineWidth = width
shapeLayer.lineDashPattern = [strokeLength, gapLength]
let path = CGMutablePath()
path.addLines(between: [point1, point2])
shapeLayer.path = path
layer.addSublayer(shapeLayer)
}
}
Then calling method looks something like this:
然后调用方法看起来像这样：
let topPoint = CGPoint(x: view.frame.midX, y: view.bounds.minY)
let bottomPoint = CGPoint(x: view.frame.midX, y: view.bounds.maxY)
view.createDashedLine(from: topPoint, to: bottomPoint, color: .black, strokeLength: 4, gapLength: 6, width: 2)
回答by Sam
Objective C
@user3230875answer helped me to understand what's needed to draw a dotted line.
so I hope this answer might help an Obj-Cseeker
Objective C
@user3230875 的答案帮助我了解绘制虚线需要什么。
所以我希望这个答案可以帮助Obj-C寻求者
//dashed line
path = [UIBezierPath bezierPath];
[path moveToPoint:CGPointMake(dashedLineStartX, dashedLineStartY)];
[path addLineToPoint:CGPointMake(dashedLineEndX, dashedLineEndY)];
path.lineWidth = 5;
[color setStroke];
CGFloat dashes[] = {4.0,8.0};
[path setLineDash:dashes count:2 phase:0.0];
path.lineCapStyle = kCGLineCapButt;
[path stroke];
