iosiphoneswiftcore-graphicsline

How to make a dashed line in swift?

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.

Solution

  • You create Dashed Lines the same way as Objective-C, except that you'll use Swift.

    Here is how you do it using UIBezierPath:

    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:

    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:

    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)