如何在Swift上使用drawRect更改三角形图形的颜色
我制作了三角形视图,称为上三角形视图。它是用来表示投票的。当它们被点击时,我想改变它们的颜色。我想从实例中获得UIColor.grayColor.setStroke,但我不知道如何实现。如果你知道的话,请告诉我怎么做。谢谢你的好意如何在Swift上使用drawRect更改三角形图形的颜色,swift,drawrect,Swift,Drawrect,我制作了三角形视图,称为上三角形视图。它是用来表示投票的。当它们被点击时,我想改变它们的颜色。我想从实例中获得UIColor.grayColor.setStroke,但我不知道如何实现。如果你知道的话,请告诉我怎么做。谢谢你的好意 class UpTriangleView: UIView { override func drawRect(rect: CGRect) { self.backgroundColor = UIColor.clearColor() // Get He
class UpTriangleView: UIView {
override func drawRect(rect: CGRect) {
self.backgroundColor = UIColor.clearColor()
// Get Height and Width
let layerHeight = self.layer.frame.height
let layerWidth = self.layer.frame.width
// Create Path
let line = UIBezierPath()
// Draw Points
line.moveToPoint(CGPointMake(0, layerHeight))
line.addLineToPoint(CGPointMake(layerWidth, layerHeight))
line.addLineToPoint(CGPointMake(layerWidth/2, 0))
line.addLineToPoint(CGPointMake(0, layerHeight))
line.closePath()
// Apply Color
UIColor.grayColor().setStroke()
UIColor.grayColor().setFill()
line.lineWidth = 3.0
line.fill()
line.stroke()
// Mask to Path
let shapeLayer = CAShapeLayer()
shapeLayer.path = line.CGPath
self.layer.mask = shapeLayer
}
}
class QATableViewCell : UITableViewCell{
@IBOutlet weak var upTriangleView: UpTriangleView!
}
向UptriangelView添加一个属性,该属性是要绘制的颜色。如果设置了颜色,则执行didSet并调用setNeedsDisplay:
class UpTriangleView: UIView {
var color = UIColor.gray {
didSet {
self.setNeedsDisplay()
}
}
override func draw(_ rect: CGRect) {
self.backgroundColor = .clear
// Get Height and Width
let layerHeight = self.layer.bounds.height
let layerWidth = self.layer.bounds.width
// Create Path
let line = UIBezierPath()
// Draw Points
line.move(to: CGPoint(x: 0, y: layerHeight))
line.addLine(to: CGPoint(x: layerWidth, y: layerHeight))
line.addLine(to: CGPoint(x: layerWidth/2, y: 0))
line.addLine(to: CGPoint(x: 0, y: layerHeight))
line.close()
// Apply Color
color.setStroke()
color.setFill()
line.lineWidth = 3.0
line.fill()
line.stroke()
// Mask to Path
let shapeLayer = CAShapeLayer()
shapeLayer.path = line.cgPath
self.layer.mask = shapeLayer
}
}
现在,在操场上进行演示,结果见下图:
let utv = UpTriangleView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
utv.color = .yellow // now triangle is yellow
utv.color = .red // now triangle is red
setNeedsDisplay将告诉iOS您的视图需要重新绘制,并且将使用新设置的颜色再次调用drawRect
谢谢你,瓦卡瓦玛…它就像一个符咒。。。真的很有帮助。