Ma question porte sur le titre.
Je ne sais pas comment ajouter une bordure dans un côté spécifique, en haut ou en bas, n'importe quel côté... layer.border
dessine la bordure de la vue entière...
Ma question porte sur le titre.
Je ne sais pas comment ajouter une bordure dans un côté spécifique, en haut ou en bas, n'importe quel côté... layer.border
dessine la bordure de la vue entière...
J'envisage de sous-classer UIView
et de remplacer drawRect
C'est exagéré ici. Pourquoi ne pas ajouter une extension sur UIView
et ajouter des sous-vues de bordure ?
@discardableResult
func addBorders(edges: UIRectEdge,
color: UIColor,
inset: CGFloat = 0.0,
thickness: CGFloat = 1.0) -> [UIView] {
var borders = [UIView]()
@discardableResult
func addBorder(formats: String...) -> UIView {
let border = UIView(frame: .zero)
border.backgroundColor = color
border.translatesAutoresizingMaskIntoConstraints = false
addSubview(border)
addConstraints(formats.flatMap {
NSLayoutConstraint.constraints(withVisualFormat: $0,
options: [],
metrics: ["inset": inset, "thickness": thickness],
views: ["border": border]) })
borders.append(border)
return border
}
if edges.contains(.top) || edges.contains(.all) {
addBorder(formats: "V:|-0-[border(==thickness)]", "H:|-inset-[border]-inset-|")
}
if edges.contains(.bottom) || edges.contains(.all) {
addBorder(formats: "V:[border(==thickness)]-0-|", "H:|-inset-[border]-inset-|")
}
if edges.contains(.left) || edges.contains(.all) {
addBorder(formats: "V:|-inset-[border]-inset-|", "H:|-0-[border(==thickness)]")
}
if edges.contains(.right) || edges.contains(.all) {
addBorder(formats: "V:|-inset-[border]-inset-|", "H:[border(==thickness)]-0-|")
}
return borders
}
// Usage:
view.addBorder(edges: [.all]) // All with default arguments
view.addBorder(edges: [.top], color: .green) // Just Top, green, default thickness
view.addBorder(edges: [.left, .right, .bottom], color: .red, thickness: 3) // All except Top, red, thickness 3
Avec ce code, vous n'êtes pas lié à votre sous-classe également, vous pouvez l'appliquer à tout ce qui hérite de UIView
- réutilisables dans votre projet, et tous les autres. Passez d'autres arguments à vos méthodes pour définir d'autres couleurs et largeurs. Nombreuses options.
Ajout de la possibilité d'arrondir les coins dans les Message original d'Adam Waite et les multiples modifications
Important ! N'oubliez pas d'ajouter 'label.layoutIfNeeded()' juste avant d'appeler 'addborder' comme indiqué précédemment.
Note : Je n'ai testé ceci que sur UILabels.
extension CALayer {
enum BorderSide {
case top
case right
case bottom
case left
case notRight
case notLeft
case topAndBottom
case all
}
enum Corner {
case topLeft
case topRight
case bottomLeft
case bottomRight
}
func addBorder(side: BorderSide, thickness: CGFloat, color: CGColor, maskedCorners: CACornerMask? = nil) {
var topWidth = frame.size.width; var bottomWidth = topWidth
var leftHeight = frame.size.height; var rightHeight = leftHeight
var topXOffset: CGFloat = 0; var bottomXOffset: CGFloat = 0
var leftYOffset: CGFloat = 0; var rightYOffset: CGFloat = 0
// Draw the corners and set side offsets
switch maskedCorners {
case [.layerMinXMinYCorner, .layerMaxXMinYCorner]: // Top only
addCorner(.topLeft, thickness: thickness, color: color)
addCorner(.topRight, thickness: thickness, color: color)
topWidth -= cornerRadius*2
leftHeight -= cornerRadius; rightHeight -= cornerRadius
topXOffset = cornerRadius; leftYOffset = cornerRadius; rightYOffset = cornerRadius
case [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]: // Bottom only
addCorner(.bottomLeft, thickness: thickness, color: color)
addCorner(.bottomRight, thickness: thickness, color: color)
bottomWidth -= cornerRadius*2
leftHeight -= cornerRadius; rightHeight -= cornerRadius
bottomXOffset = cornerRadius
case [.layerMinXMinYCorner, .layerMinXMaxYCorner]: // Left only
addCorner(.topLeft, thickness: thickness, color: color)
addCorner(.bottomLeft, thickness: thickness, color: color)
topWidth -= cornerRadius; bottomWidth -= cornerRadius
leftHeight -= cornerRadius*2
leftYOffset = cornerRadius; topXOffset = cornerRadius; bottomXOffset = cornerRadius;
case [.layerMaxXMinYCorner, .layerMaxXMaxYCorner]: // Right only
addCorner(.topRight, thickness: thickness, color: color)
addCorner(.bottomRight, thickness: thickness, color: color)
topWidth -= cornerRadius; bottomWidth -= cornerRadius
rightHeight -= cornerRadius*2
rightYOffset = cornerRadius
case [.layerMaxXMinYCorner, .layerMaxXMaxYCorner, // All
.layerMinXMaxYCorner, .layerMinXMinYCorner]:
addCorner(.topLeft, thickness: thickness, color: color)
addCorner(.topRight, thickness: thickness, color: color)
addCorner(.bottomLeft, thickness: thickness, color: color)
addCorner(.bottomRight, thickness: thickness, color: color)
topWidth -= cornerRadius*2; bottomWidth -= cornerRadius*2
topXOffset = cornerRadius; bottomXOffset = cornerRadius
leftHeight -= cornerRadius*2; rightHeight -= cornerRadius*2
leftYOffset = cornerRadius; rightYOffset = cornerRadius
default: break
}
// Draw the sides
switch side {
case .top:
addLine(x: topXOffset, y: 0, width: topWidth, height: thickness, color: color)
case .right:
addLine(x: frame.size.width - thickness, y: rightYOffset, width: thickness, height: rightHeight, color: color)
case .bottom:
addLine(x: bottomXOffset, y: frame.size.height - thickness, width: bottomWidth, height: thickness, color: color)
case .left:
addLine(x: 0, y: leftYOffset, width: thickness, height: leftHeight, color: color)
// Multiple Sides
case .notRight:
addLine(x: topXOffset, y: 0, width: topWidth, height: thickness, color: color)
addLine(x: 0, y: leftYOffset, width: thickness, height: leftHeight, color: color)
addLine(x: bottomXOffset, y: frame.size.height - thickness, width: bottomWidth, height: thickness, color: color)
case .notLeft:
addLine(x: topXOffset, y: 0, width: topWidth, height: thickness, color: color)
addLine(x: frame.size.width - thickness, y: rightYOffset, width: thickness, height: rightHeight, color: color)
addLine(x: bottomXOffset, y: frame.size.height - thickness, width: bottomWidth, height: thickness, color: color)
case .topAndBottom:
addLine(x: topXOffset, y: 0, width: topWidth, height: thickness, color: color)
addLine(x: bottomXOffset, y: frame.size.height - thickness, width: bottomWidth, height: thickness, color: color)
case .all:
addLine(x: topXOffset, y: 0, width: topWidth, height: thickness, color: color)
addLine(x: frame.size.width - thickness, y: rightYOffset, width: thickness, height: rightHeight, color: color)
addLine(x: bottomXOffset, y: frame.size.height - thickness, width: bottomWidth, height: thickness, color: color)
addLine(x: 0, y: leftYOffset, width: thickness, height: leftHeight, color: color)
}
}
private func addLine(x: CGFloat, y: CGFloat, width: CGFloat, height: CGFloat, color: CGColor) {
let border = CALayer()
border.frame = CGRect(x: x, y: y, width: width, height: height)
border.backgroundColor = color
addSublayer(border)
}
private func addCorner(_ corner: Corner, thickness: CGFloat, color: CGColor) {
// Set default to top left
let width = frame.size.width; let height = frame.size.height
var x = cornerRadius
var y = cornerRadius
var startAngle: CGFloat = .pi; var endAngle: CGFloat = .pi*3/2
switch corner {
case .bottomLeft:
y = height - cornerRadius
startAngle = .pi/2; endAngle = .pi
case .bottomRight:
x = width - cornerRadius
y = height - cornerRadius
startAngle = 0; endAngle = .pi/2
case .topRight:
x = width - cornerRadius
startAngle = .pi*3/2; endAngle = 0
default: break
}
let cornerPath = UIBezierPath(arcCenter: CGPoint(x: x, y: y),
radius: cornerRadius - thickness,
startAngle: startAngle,
endAngle: endAngle,
clockwise: true)
let cornerShape = CAShapeLayer()
cornerShape.path = cornerPath.cgPath
cornerShape.lineWidth = thickness
cornerShape.strokeColor = color
cornerShape.fillColor = nil
addSublayer(cornerShape)
}
}
La meilleure façon pour moi est une catégorie sur UIView, mais adding views
au lieu de CALayers, donc on peut take advantage of AutoresizingMasks
pour s'assurer que les bordures sont redimensionnées en même temps que la vue supérieure.
Objectif C
- (void)addTopBorderWithColor:(UIColor *)color andWidth:(CGFloat) borderWidth {
UIView *border = [UIView new];
border.backgroundColor = color;
[border setAutoresizingMask:UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleBottomMargin];
border.frame = CGRectMake(0, 0, self.frame.size.width, borderWidth);
[self addSubview:border];
}
- (void)addBottomBorderWithColor:(UIColor *)color andWidth:(CGFloat) borderWidth {
UIView *border = [UIView new];
border.backgroundColor = color;
[border setAutoresizingMask:UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleTopMargin];
border.frame = CGRectMake(0, self.frame.size.height - borderWidth, self.frame.size.width, borderWidth);
[self addSubview:border];
}
- (void)addLeftBorderWithColor:(UIColor *)color andWidth:(CGFloat) borderWidth {
UIView *border = [UIView new];
border.backgroundColor = color;
border.frame = CGRectMake(0, 0, borderWidth, self.frame.size.height);
[border setAutoresizingMask:UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleRightMargin];
[self addSubview:border];
}
- (void)addRightBorderWithColor:(UIColor *)color andWidth:(CGFloat) borderWidth {
UIView *border = [UIView new];
border.backgroundColor = color;
[border setAutoresizingMask:UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin];
border.frame = CGRectMake(self.frame.size.width - borderWidth, 0, borderWidth, self.frame.size.height);
[self addSubview:border];
}
Swift 5
func addTopBorder(with color: UIColor?, andWidth borderWidth: CGFloat) {
let border = UIView()
border.backgroundColor = color
border.autoresizingMask = [.flexibleWidth, .flexibleBottomMargin]
border.frame = CGRect(x: 0, y: 0, width: frame.size.width, height: borderWidth)
addSubview(border)
}
func addBottomBorder(with color: UIColor?, andWidth borderWidth: CGFloat) {
let border = UIView()
border.backgroundColor = color
border.autoresizingMask = [.flexibleWidth, .flexibleTopMargin]
border.frame = CGRect(x: 0, y: frame.size.height - borderWidth, width: frame.size.width, height: borderWidth)
addSubview(border)
}
func addLeftBorder(with color: UIColor?, andWidth borderWidth: CGFloat) {
let border = UIView()
border.backgroundColor = color
border.frame = CGRect(x: 0, y: 0, width: borderWidth, height: frame.size.height)
border.autoresizingMask = [.flexibleHeight, .flexibleRightMargin]
addSubview(border)
}
func addRightBorder(with color: UIColor?, andWidth borderWidth: CGFloat) {
let border = UIView()
border.backgroundColor = color
border.autoresizingMask = [.flexibleHeight, .flexibleLeftMargin]
border.frame = CGRect(x: frame.size.width - borderWidth, y: 0, width: borderWidth, height: frame.size.height)
addSubview(border)
}
Swift 3.0
Swift 4.1
extension CALayer {
func addBorder(edge: UIRectEdge, color: UIColor, thickness: CGFloat) {
let border = CALayer()
switch edge {
case UIRectEdge.top:
border.frame = CGRect(x: 0, y: 0, width: frame.width, height: thickness)
case UIRectEdge.bottom:
border.frame = CGRect(x:0, y: frame.height - thickness, width: frame.width, height:thickness)
case UIRectEdge.left:
border.frame = CGRect(x:0, y:0, width: thickness, height: frame.height)
case UIRectEdge.right:
border.frame = CGRect(x: frame.width - thickness, y: 0, width: thickness, height: frame.height)
default: do {}
}
border.backgroundColor = color.cgColor
addSublayer(border)
}
}
Sous-classe UIView
et mettre en œuvre drawRect:
dans votre sous-classe, par exemple :
Objective-c
- (void)drawRect:(CGRect)rect {
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextMoveToPoint(context, CGRectGetMinX(rect), CGRectGetMinY(rect));
CGContextAddLineToPoint(context, CGRectGetMaxX(rect), CGRectGetMinY(rect));
CGContextSetStrokeColorWithColor(context, [[UIColor redColor] CGColor] );
CGContextSetLineWidth(context, 2.0);
CGContextStrokePath(context);
}
Swift 4
override func draw(_ rect: CGRect) {
let cgContext = UIGraphicsGetCurrentContext()
cgContext?.move(to: CGPoint(x: rect.minX, y: rect.minY))
cgContext?.addLine(to: CGPoint(x: rect.maxX, y: rect.minY))
cgContext?.setStrokeColor(UIColor.red.cgColor)
cgContext?.setLineWidth(2.0)
cgContext?.strokePath()
}
Cela dessine une ligne rouge de 2 pixels comme bordure supérieure. Toutes les autres variations que vous mentionnez sont laissées comme un exercice trivial pour le lecteur.
Guide de programmation de Quartz 2D est recommandé.
Prograide est une communauté de développeurs qui cherche à élargir la connaissance de la programmation au-delà de l'anglais.
Pour cela nous avons les plus grands doutes résolus en français et vous pouvez aussi poser vos propres questions ou résoudre celles des autres.