我正在尝试按照图片中的模型创建一个UIView。虽然,我似乎对我的代码有一些问题。知道为什么吗?
在评论的帮助下解决了!正确的代码已更新!
更新:我创建了一个自定义的UIView类 这是我的新代码,基于评论。
drawLine取自:Draw a line with UIBezierPath
答案 0 :(得分:5)
实现上述形象的代码:
//Post this function in your TableViewController
func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
let view = HeaderTableView()
view.title.text = "THIS WEEK"
return view
}
//Custom UIView Class
class CustomView: UIView {
var shouldSetupConstraints = true
var title: UILabel!
// Only override draw() if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
override func draw(_ rect: CGRect) {
let textStartX = Int((title.frame.minX))
let textEndX = Int((title.frame.maxX))
let midY = Int(self.frame.midY)
self.drawLine(startX: 8, toEndingX: textStartX - 8, startingY: midY, toEndingY: midY, ofColor: UIColor.white, widthOfLine: 1, inView: self)
self.drawLine(startX: textEndX + 8, toEndingX: Int(self.frame.maxX) - 8, startingY: midY, toEndingY: midY, ofColor: UIColor.white, widthOfLine: 1, inView: self)
}
override init(frame: CGRect) {
super.init(frame: frame)
title = UILabel()
self.addSubview(title)
title.textAlignment = .center
title.textColor = UIColor.white
title.translatesAutoresizingMaskIntoConstraints = false
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func updateConstraints() {
if(shouldSetupConstraints) {
// AutoLayout constraints
let xConstraint = NSLayoutConstraint(item: title, attribute: .centerX, relatedBy: .equal, toItem: self, attribute: .centerX, multiplier: 1, constant: 0)
let yConstraint = NSLayoutConstraint(item: title, attribute: .centerY, relatedBy: .equal, toItem: self, attribute: .centerY, multiplier: 1, constant: 0)
self.addConstraints([xConstraint, yConstraint])
shouldSetupConstraints = false
}
super.updateConstraints()
}
func drawLine(startX: Int, toEndingX endX: Int, startingY startY: Int, toEndingY endY: Int, ofColor lineColor: UIColor, widthOfLine lineWidth: CGFloat, inView view: UIView) {
let path = UIBezierPath()
path.move(to: CGPoint(x: startX, y: startY))
path.addLine(to: CGPoint(x: endX, y: endY))
let shapeLayer = CAShapeLayer()
shapeLayer.path = path.cgPath
shapeLayer.strokeColor = lineColor.cgColor
shapeLayer.lineWidth = lineWidth
view.layer.addSublayer(shapeLayer)
}
}
现金:
答案 1 :(得分:0)
在Swift 4.1中画线
class MyViewController: UIViewController {
@IBOutlet weak var imgViewDraw: UIImageView!
var lastPoint = CGPoint.zero
var red: CGFloat = 0.0
var green: CGFloat = 0.0
var blue: CGFloat = 0.0
var brushWidth: CGFloat = 10.0
var opacity: CGFloat = 1.0
var isSwiping:Bool!
var previousPoint1 = CGPoint()
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
//MARK: Touch events
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
isSwiping = false
if let touch = touches.first{
lastPoint = touch.location(in: imgViewDraw)
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
isSwiping = true;
if let touch = touches.first{
let currentPoint = touch.location(in: imgViewDraw)
UIGraphicsBeginImageContext(self.imgViewDraw.frame.size)
self.imgViewDraw.image?.draw(in: CGRect(x:0, y:0,width:self.imgViewDraw.frame.size.width, height:self.imgViewDraw.frame.size.height))
UIGraphicsGetCurrentContext()?.move(to: CGPoint(x: lastPoint.x, y: lastPoint.y))
UIGraphicsGetCurrentContext()?.addLine(to: CGPoint(x: currentPoint.x, y: currentPoint.y))
UIGraphicsGetCurrentContext()?.setLineCap(CGLineCap.round)
UIGraphicsGetCurrentContext()?.setLineWidth(self.brushWidth)
UIGraphicsGetCurrentContext()?.setStrokeColor(red: red, green: green, blue: blue, alpha: 1.0)
UIGraphicsGetCurrentContext()?.strokePath()
self.imgViewDraw.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
lastPoint = currentPoint
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
if(!isSwiping) {
// This is a single touch, draw a point
UIGraphicsBeginImageContext(self.imgViewDraw.frame.size)
self.imgViewDraw.image?.draw(in: CGRect(x:0, y:0,width:self.imgViewDraw.frame.size.width, height:self.imgViewDraw.frame.size.height))
UIGraphicsGetCurrentContext()?.setLineCap(CGLineCap.round)
UIGraphicsGetCurrentContext()?.setLineWidth(self.brushWidth)
UIGraphicsGetCurrentContext()?.move(to: CGPoint(x: lastPoint.x, y: lastPoint.y))
UIGraphicsGetCurrentContext()?.addLine(to: CGPoint(x: lastPoint.x, y: lastPoint.y))
UIGraphicsGetCurrentContext()?.setStrokeColor(red: red, green: green, blue: blue, alpha: 1.0)
UIGraphicsGetCurrentContext()?.strokePath()
self.imgViewDraw.image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
}
}
}