I have a CAShapeLayer that I am adding to the center of a UIView, but instead of appearing in the center, it appears in the top left corner of the UIView.
Here's the view setup:
let trayProgress: UIView = {
let view = UIView()
view.backgroundColor = .yellow
let trackLayer = CAShapeLayer()
let circularPath = UIBezierPath(arcCenter: view.center, radius: 20, startAngle: -CGFloat.pi / 2, endAngle: CGFloat.pi * 2, clockwise: false)
trackLayer.path = circularPath.cgPath
trackLayer.strokeColor = UIColor.lightGray.cgColor
trackLayer.lineWidth = 6
trackLayer.fillColor = UIColor.clear.cgColor
view.layer.addSublayer(trackLayer)
return view
}()
Here's what is showing in the view (I expect the gray circle to be in the center of the yellow view):
I have also tried to replace view.center with CGPoint(x: view.center.x, y: view.center.y), but I get the same result.
Can anyone tell me why this is happening and how I can fix it? Thanks!
The problem is in part this line:
arcCenter: view.center
That makes no sense, because the view’s center is where it is in its superview. You want to make the shape layer’s frame the same as the view’s bounds! The arc center should then be the shape layer’s own center (which, because it is a layer, is its position).
But another part of the problem is that in the code you’ve shown neither the view nor the shape layer has any size. You cannot create the shape layer until the view has size.
Example (I have starred the key changes in the code):
let trayProgress: UIView = {
let view = UIView(frame:CGRect(x: 30, y: 60, width: 50, height: 50)) // *
view.backgroundColor = .yellow
let trackLayer = CAShapeLayer()
trackLayer.frame = view.bounds // *
let circularPath = UIBezierPath(arcCenter: trackLayer.position, // *
radius: 20, startAngle: -CGFloat.pi / 2, endAngle: CGFloat.pi * 2, clockwise: false)
trackLayer.path = circularPath.cgPath
trackLayer.strokeColor = UIColor.lightGray.cgColor
trackLayer.lineWidth = 6
trackLayer.fillColor = UIColor.clear.cgColor
view.layer.addSublayer(trackLayer)
return view
}()
Result:
You can tweak that, of course. For example you can move the center of the view to wherever you like.
Related
I am trying below code to draw shape and that's okay but UIView background color not showing since I Have given orange color to View
See my code:
let myView = UIView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
myView.backgroundColor = .orange
let circlePath = UIBezierPath(arcCenter: CGPoint(x: myView.bounds.size.width / 2, y: 0), radius: myView.bounds.size.height, startAngle: 0.0, endAngle: .pi, clockwise: false)
let circleShape = CAShapeLayer()
circleShape.masksToBounds = false
circleShape.path = circlePath.cgPath
circleShape.fillColor = UIColor.orange.cgColor
circleShape.strokeColor = UIColor.orange.cgColor
myView.layer.mask = circleShape
print(myView)
Output At Playground:
Try this code:
let myView = UIView(frame: CGRect(x: 0, y: 0, width: 200, height: 200))
myView.backgroundColor = .orange
let circlePath = UIBezierPath(arcCenter: myView.center,
radius: myView.bounds.size.width / 2,
startAngle: 0.0,
endAngle: .pi,
clockwise: false)
let circleShape = CAShapeLayer()
circleShape.path = circlePath.cgPath
myView.layer.mask = circleShape
I think you don't see expecting result because of wrong arcCenter or start and end angels
result of the code:
The issue seems to be with your circlePath, that has:
1) Wrong arcCenter (CGPoint's y is not centered)
2) Radius (It should be half the view's height/width, considering height = width and you need a circle)
3) Angle (It should be 360 degrees)
Replace its definition with:
let circlePath = UIBezierPath(arcCenter: myView.center, radius: myView.bounds.height/2, startAngle: 0.0, endAngle: .pi * 2, clockwise: false)
and it should work as intended...
that's okay but UIView background color not showing since I Have given
orange color to View
The path you've used doesn't even display a layer since you've specified its corner radius to be the same as its height, and you've applied the generated supposedly invisible layer to be your view's mask.
A few observations:
You are just looking at a visual representation of the path, not of the view. To see the view, you should set the liveView of the PlaygroundPage:
import PlaygroundSupport
And
PlaygroundPage.current.liveView = myView
PlaygroundPage.current.needsIndefiniteExecution = true
An an aside, your circle view is going from 0 to π counterclockwise. I.e. that is the top half of a circle. So if the circle’s center has a y of 0, that means your path is above the view and doesn’t overlap with it. Either set it to go clockwise (to get the bottom half of a circle) or move the y down (so the top half half of the circle overlaps the view).
I find that playgrounds resize their liveView (even if I set wantsFullScreenLiveView to false), so if I want a view of a particular size, I use a “container view”. I.e., I will add myView as a subview of containerView, add constraints to put it in the center of that container, and then set containerView as the liveView.
Only tangentially related, but you’re setting the color of the shape layer of the mask to be orange. Masks only use their alpha channel, so using orange is meaningless. We’d generally set masks to be white, but I just wanted to make sure we didn’t conflate the color of the mask with the color of the masked view.
So, pulling that all together:
import UIKit
import PlaygroundSupport
// create container
let containerView = UIView()
containerView.translatesAutoresizingMaskIntoConstraints = false
// create view that we'll mask with shape layer
let rect = CGRect(x: 0, y: 0, width: 200, height: 200)
let myView = UIView()
myView.translatesAutoresizingMaskIntoConstraints = false
myView.backgroundColor = .orange
myView.clipsToBounds = true
containerView.addSubview(myView)
// create mask
let circlePath = UIBezierPath(arcCenter: CGPoint(x: rect.midX, y: rect.minY), radius: rect.height, startAngle: 0, endAngle: .pi, clockwise: true)
let circleShape = CAShapeLayer()
circleShape.masksToBounds = false
circleShape.path = circlePath.cgPath
circleShape.fillColor = UIColor.white.cgColor
circleShape.strokeColor = UIColor.white.cgColor
myView.layer.mask = circleShape
// center masked view in container
NSLayoutConstraint.activate([
myView.centerXAnchor.constraint(equalTo: containerView.centerXAnchor),
myView.centerYAnchor.constraint(equalTo: containerView.centerYAnchor),
myView.widthAnchor.constraint(equalToConstant: 200),
myView.heightAnchor.constraint(equalToConstant: 200)
])
// show it
PlaygroundPage.current.liveView = containerView
PlaygroundPage.current.needsIndefiniteExecution = true
That yields:
So, by making the arc go clockwise and by using the liveView, we can now see it. Obviously an arc whose center is at midX, minY and with a radius of height, cannot show the full half circle. You’d have to set the radius to be width / 2 (or increase the width of the rect or whatever) if you wanted to see the full half circle.
Just remove path.move(to:) calls everywhere after drawing. That's helped me with the same issue
I'm trying to replicate the default camera button on iOS devices:
I'm able to create a white circular button with black button within it. However, the black button is also filled, instead of just being a thin circle.
This is what I have (most of it has been copied from different sources and put together, so the code isn't efficient)
The object represents the button,
func applyRoundCorner(_ object: AnyObject) {
//object.layer.shadowColor = UIColor.black.cgColor
//object.layer.shadowOffset = CGSize(width: 0.0, height: 2.0)
object.layer.cornerRadius = (object.frame.size.width)/2
object.layer.borderColor = UIColor.black.cgColor
object.layer.borderWidth = 5
object.layer.masksToBounds = true
//object.layer.shadowRadius = 1.0
//object.layer.shadowOpacity = 0.5
var CircleLayer = CAShapeLayer()
let center = CGPoint (x: object.frame.size.width / 2, y: object.frame.size.height / 2)
let circleRadius = object.frame.size.width / 6
let circlePath = UIBezierPath(arcCenter: center, radius: circleRadius, startAngle: CGFloat(M_PI), endAngle: CGFloat(M_PI * 2), clockwise: true)
CircleLayer.path = circlePath.cgPath
CircleLayer.strokeColor = UIColor.black.cgColor
//CircleLayer.fillColor = UIColor.blue.cgColor
CircleLayer.lineWidth = 1
CircleLayer.strokeStart = 0
CircleLayer.strokeEnd = 1
object.layer.addSublayer(CircleLayer)
}
Basic Approach
You could do it like this (for the purpose of demonstration, I would do the button programmatically, using a playground):
let buttonWidth = 100.0
let button = UIButton(frame: CGRect(x: 0, y: 0, width: buttonWidth, height: buttonWidth))
button.backgroundColor = .white
button.layer.cornerRadius = button.frame.width / 2
Drawing Part:
So, after adding the button and do the desired setup (make it circular), here is part of how you could draw a circle in it:
let circlePath = UIBezierPath(arcCenter: CGPoint(x: buttonWidth / 2,y: buttonWidth / 2), radius: 40.0, startAngle: 0, endAngle: CGFloat.pi * 2, clockwise: true)
let circleLayer = CAShapeLayer()
circleLayer.path = circlePath.cgPath
circleLayer.fillColor = UIColor.clear.cgColor
circleLayer.strokeColor = UIColor.black.cgColor
circleLayer.lineWidth = 2.5
// adding the layer into the button:
button.layer.addSublayer(circleLayer)
Probably, circleLayer.fillColor = UIColor.clear.cgColor is the part you missing 🙂.
Therefore:
Back to your case:
Aside Bar Tip:
For implementing applyRoundCorner, I would suggest to let it has only the job for rounding the view, and then create another function to add the circle inside the view. And that's for avoiding any naming conflict, which means that when reading "applyRoundCorner" I would not assume that it is also would add circle to my view! So:
func applyRoundedCorners(for view: UIView) {
view.layer.cornerRadius = view.frame.size.width / 2
view.layer.borderColor = UIColor.white.cgColor
view.layer.borderWidth = 5.0
view.layer.masksToBounds = true
}
func drawCircle(in view: UIView) {
let circlePath = UIBezierPath(arcCenter: CGPoint(x: view.frame.size.width / 2,y: view.frame.size.width / 2),
radius: view.frame.size.width / 2.5,
startAngle: 0,
endAngle: CGFloat.pi * 2,
clockwise: true)
let shapeLayer = CAShapeLayer()
shapeLayer.path = circlePath.cgPath
shapeLayer.fillColor = UIColor.clear.cgColor
shapeLayer.strokeColor = UIColor.black.cgColor
shapeLayer.lineWidth = 2.5
button.layer.addSublayer(shapeLayer)
}
and now:
applyRoundedCorners(for: button)
drawCircle(in: button)
That's seems to be better. From another aspect, consider that you want to make a view to be circular without add a circle in it, with separated methods you could simply applyRoundedCorners(for: myView) without the necessary of adding a circle in it.
Furthermore:
As you can see, I changed AnyObject to UIView, it seems to be more logical to your case. So here is a cool thing that we could do:
extension UIView {
func applyRoundedCorners(for view: UIView) {
view.layer.cornerRadius = view.frame.size.width / 2
view.layer.borderColor = UIColor.white.cgColor
view.layer.borderWidth = 5.0
view.layer.masksToBounds = true
}
func drawCircle(in view: UIView) {
let circlePath = UIBezierPath(arcCenter: CGPoint(x: view.frame.size.width / 2,y: view.frame.size.width / 2),
radius: view.frame.size.width / 2.5,
startAngle: 0,
endAngle: CGFloat.pi * 2,
clockwise: true)
let shapeLayer = CAShapeLayer()
shapeLayer.path = circlePath.cgPath
shapeLayer.fillColor = UIColor.clear.cgColor
shapeLayer.strokeColor = UIColor.black.cgColor
shapeLayer.lineWidth = 2.5
button.layer.addSublayer(shapeLayer)
}
}
Now both applyRoundedCorners and drawCircle are implicitly included to the UIView (which means UIButton), instead of passing the button to these functions, you would be able to:
button.applyRoundedCorners()
button.drawCircle()
You just need to add circle Shape layer with lesser width and height
Try this code
func applyRoundCorner(_ object: UIButton) {
object.layer.cornerRadius = (object.frame.size.width)/2
object.layer.borderColor = UIColor.black.cgColor
object.layer.borderWidth = 5
object.layer.masksToBounds = true
let anotherFrame = CGRect(x: 12, y: 12, width: object.bounds.width - 24, height: object.bounds.height - 24)
let circle = CAShapeLayer()
let path = UIBezierPath(arcCenter: object.center, radius: anotherFrame.width / 2, startAngle: 0, endAngle: .pi * 2, clockwise: true)
circle.path = path.cgPath
circle.strokeColor = UIColor.black.cgColor
circle.lineWidth = 1.0
circle.fillColor = UIColor.clear.cgColor
object.layer.addSublayer(circle)
}
Note: Change frame value according to your requirements and best user experience
Output
I have no doubt there are a million different ways to approach this problem, this is just one...
I started with a UIButton for simplicity and speed, I might consider actually starting with a UIImage and simply setting the image properties of the button, but it would depend a lot on what I'm trying to achieve
internal extension FloatingPoint {
var degreesToRadians: Self { return self * .pi / 180 }
var radiansToDegrees: Self { return self * 180 / .pi }
}
class RoundButton: UIButton {
override func draw(_ rect: CGRect) {
makeButtonImage()?.draw(at: CGPoint(x: 0, y: 0))
}
func makeButtonImage() -> UIImage? {
let size = bounds.size
UIGraphicsBeginImageContext(CGSize(width: size.width, height: size.height))
defer {
UIGraphicsEndImageContext()
}
guard let ctx = UIGraphicsGetCurrentContext() else {
return nil
}
let center = CGPoint(x: size.width / 2.0, y: size.height / 2.0)
// Want to "over fill" the image area, so the mask can be applied
// to the entire image
let radius = min(size.width / 2.0, size.height / 2.0)
let innerRadius = radius * 0.75
let innerCircle = UIBezierPath(arcCenter: center,
radius: innerRadius,
startAngle: CGFloat(0.0).degreesToRadians,
endAngle: CGFloat(360.0).degreesToRadians,
clockwise: true)
// The color doesn't matter, only it's alpha level
UIColor.red.setStroke()
innerCircle.lineWidth = 4.0
innerCircle.stroke(with: .normal, alpha: 1.0)
let circle = UIBezierPath(arcCenter: center,
radius: radius,
startAngle: CGFloat(0.0).degreesToRadians,
endAngle: CGFloat(360.0).degreesToRadians,
clockwise: true)
UIColor.clear.setFill()
ctx.fill(bounds)
UIColor.white.setFill()
circle.fill(with: .sourceOut, alpha: 1.0)
return UIGraphicsGetImageFromCurrentImageContext()
}
}
nb: This is unoptimised! I would consider caching the result of makeButtonImage and invalidate it when the state/size of the button changes, just beware of that
Why is this approach any "better" then any other? I just want to say, it's not, but what it does create, is a "cut out" of the inner circle
It's a nitpick on my part, but I think it looks WAY better and is a more flexible solution, as you don't "need" a inner circle stroke color, blah, blah, blah
The solution makes use of the CoreGraphics CGBlendModes
Of course I might just do the whole thing in PaintCodeApp and be done with it
How can I fix this issue?
The image is set with constraints in the storyboard; the other circle is set with these lines of code:
let centerY = profileImage.center.y+20+(self.navigationController?.navigationBar.frame.size.height)!
let centerX = profileImage.center.x
let center = CGPoint(x: centerX, y: centerY)
let trackLayer = CAShapeLayer()
let circularPath = UIBezierPath(arcCenter: center, radius: (profileImage.frame.width/2)+2, startAngle: -CGFloat.pi-CGFloat.pi/2, endAngle: CGFloat.pi/2, clockwise: true)
trackLayer.path = circularPath.cgPath
trackLayer.strokeColor = Functions.hexStringToUIColor(hex: "#3859B9").cgColor
trackLayer.lineWidth = 3
trackLayer.lineCap = kCALineCapRound
trackLayer.fillColor = UIColor.clear.cgColor
view.layer.addSublayer(trackLayer)
On iPhone 7 (the one on the right) seems to be right.
Using fixed values for navigation's or status' bar height will lead to such errors. You should position your layer according to the image view. For that you can simply assign the frame of the image view to your layer:
trackLayer.frame = profileImage.frame
Since the layout may change for several reasons (e.g. device rotation), you should do this in viewDidLayoutSubviews of your view controller.
Since the frame of the layer is now smaller than in your example, you should create the center with:
let center = CGPoint(x: profileImage.bounds.midX, y: profileImage.bounds.midY)
override func viewDidLayoutSubviews() {
let centerY = profileImage.center.y+20+(self.navigationController?.navigationBar.frame.size.height)!
let centerX = profileImage.center.x
let center = CGPoint(x: centerX, y: centerY)
let trackLayer = CAShapeLayer()
let circularPath = UIBezierPath(arcCenter: center, radius: (profileImage.frame.width/2)+2, startAngle: -CGFloat.pi-CGFloat.pi/2, endAngle: CGFloat.pi/2, clockwise: true)
trackLayer.path = circularPath.cgPath
trackLayer.strokeColor = Functions.hexStringToUIColor(hex: "#3859B9").cgColor
trackLayer.lineWidth = 3
trackLayer.lineCap = kCALineCapRound
trackLayer.fillColor = UIColor.clear.cgColor
view.layer.addSublayer(trackLayer)
}
OR in write the code in viewDidAppear without delay
This would fix the issue.
Add the layer to profileImage.layer.
trackLayer.frame = profileImage.bounds
Full code should be like this:
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
let center = CGPoint(x: profileImage.bounds.midX,
y: profileImage.bounds.midY)
let trackLayer = CAShapeLayer()
trackLayer.frame = profileImage.frame
let circularPath = UIBezierPath(arcCenter: center,
radius: (profileImage.frame.width / 2) + 2,
startAngle: -CGFloat.pi - CGFloat.pi / 2,
endAngle: CGFloat.pi / 2, clockwise: true)
trackLayer.path = circularPath.cgPath
trackLayer.strokeColor = Functions.hexStringToUIColor(hex: "#3859B9").cgColor
trackLayer.lineWidth = 3
trackLayer.lineCap = kCALineCapRound
trackLayer.fillColor = UIColor.clear.cgColor
profileImage.layer.addSublayer(trackLayer)
}
Using interface builder:
Drag UIView and drop above the imageview
Change view custom class to CirculerProgressView
Set center X and Y constraints with imageview center
Set height and width constraints(greater then imageView height & width)
#IBDesignable class CirculerProgressView: UIView {
override class var layerClass: AnyClass {
return CAShapeLayer.self
}
override func draw(_ rect: CGRect) {
super.draw(rect)
setupLayer()
}
private func setupLayer() {
let trackLayer = layer as! CAShapeLayer
let center = CGPoint(x: frame.width/2, y: frame.height/2)
let circularPath = UIBezierPath(arcCenter: center, radius: frame.width/2, startAngle: -CGFloat.pi-CGFloat.pi/2, endAngle: CGFloat.pi/2, clockwise: true)
trackLayer.path = circularPath.cgPath
trackLayer.strokeColor = UIColor.blue.cgColor
trackLayer.lineWidth = 3
trackLayer.lineCap = kCALineCapRound
trackLayer.fillColor = UIColor.clear.cgColor
}}
I draw a donut chart with CAShapeLayers arcs. I draw it by putting one on top of another and the problem that underneath layers edges are visible.
code of drawing is following
for (index, item) in values.enumerated() {
var currentValue = previousValue + item.value
previousValue = currentValue
if index == values.count - 1 {
currentValue = 100
}
let layer = CAShapeLayer()
let path = UIBezierPath()
let separatorLayer = CAShapeLayer()
let separatorPath = UIBezierPath()
let radius: CGFloat = self.frame.width / 2 - lineWidth / 2
let center: CGPoint = CGPoint(x: self.bounds.width / 2, y: self.bounds.width / 2)
separatorPath.addArc(withCenter: center, radius: radius, startAngle: percentToRadians(percent: -25), endAngle: percentToRadians(percent: CGFloat(currentValue - 25 + 0.2)), clockwise: true)
separatorLayer.path = separatorPath.cgPath
separatorLayer.fillColor = UIColor.clear.cgColor
separatorLayer.strokeColor = UIColor.white.cgColor
separatorLayer.lineWidth = lineWidth
separatorLayer.contentsScale = UIScreen.main.scale
self.layer.addSublayer(separatorLayer)
separatorLayer.add(createGraphAnimation(), forKey: nil)
separatorLayer.zPosition = -(CGFloat)(index)
path.addArc(withCenter: center, radius: radius, startAngle: percentToRadians(percent: -25), endAngle: percentToRadians(percent: CGFloat(currentValue - 25)), clockwise: true)
layer.path = path.cgPath
layer.fillColor = UIColor.clear.cgColor
layer.strokeColor = item.color.cgColor
layer.lineWidth = lineWidth
layer.contentsScale = UIScreen.main.scale
layer.shouldRasterize = true
layer.rasterizationScale = UIScreen.main.scale
layer.allowsEdgeAntialiasing = true
separatorLayer.addSublayer(layer)
layer.add(createGraphAnimation(), forKey: nil)
layer.zPosition = -(CGFloat)(index)
What am I doing wrong ?
UPD
Tried code
let mask = CAShapeLayer()
mask.frame = CGRect(x: 0, y: 0, width: radius * 2, height: radius * 2)
mask.fillColor = nil
mask.strokeColor = UIColor.white.cgColor
mask.lineWidth = lineWidth * 2
let maskPath = CGMutablePath()
maskPath.addArc(center: CGPoint(x: self.radius, y: self.radius), radius: radius, startAngle: 0, endAngle: 2 * .pi, clockwise: true)
maskPath.closeSubpath()
mask.path = maskPath
self.layer.mask = mask
but it masks only inner edges, outer still has fringe
The fringe you're seeing happens because you're drawing exactly the same shape in the same position twice, and alpha compositing (as commonly implemented) is not designed to handle that. Porter and Duff's paper, “Compositing Digital Images”, which introduced alpha compositing, discusses the problem:
We must remember that our basic assumption about the
division of subpixel areas by geometric objects breaks
down in the face of input pictures with correlated mattes.
When one picture appears twice in a compositing expression,
we must take care with our computations of F A and
F B. Those listed in the table are correct only for uncorrelated
pictures.
When it says “matte”, it basically means transparency. When it says “uncorrelated pictures”, it means two pictures whose transparent areas have no special relationship. But in your case, your two pictures do have a special relationship: the pictures are transparent in exactly the same areas!
Here's a self-contained test that reproduces your problem:
private func badVersion() {
let center = CGPoint(x: view.bounds.width / 2, y: view.bounds.height / 2)
let radius: CGFloat = 100
let ringWidth: CGFloat = 44
let ring = CAShapeLayer()
ring.frame = view.bounds
ring.fillColor = nil
ring.strokeColor = UIColor.red.cgColor
ring.lineWidth = ringWidth
let ringPath = CGMutablePath()
ringPath.addArc(center: center, radius: radius, startAngle: 0, endAngle: 2 * .pi, clockwise: true)
ringPath.closeSubpath()
ring.path = ringPath
view.layer.addSublayer(ring)
let wedge = CAShapeLayer()
wedge.frame = view.bounds
wedge.fillColor = nil
wedge.strokeColor = UIColor.darkGray.cgColor
wedge.lineWidth = ringWidth
wedge.lineCap = kCALineCapButt
let wedgePath = CGMutablePath()
wedgePath.addArc(center: center, radius: radius, startAngle: 0.1, endAngle: 0.6, clockwise: false)
wedge.path = wedgePath
view.layer.addSublayer(wedge)
}
Here's the part of the screen that shows the problem:
One way to fix this is to draw the colors beyond the edges of the ring, and use a mask to clip them to the ring shape.
I'll change my code so that instead of drawing a red ring, and part of a gray ring on top of it, I draw a red disc, and a gray wedge on top of it:
If you zoom in, you can see that this still shows the red fringe at the edge of the gray wedge. So the trick is to use a ring-shaped mask to get the final shape. Here's the shape of the mask, drawn in white on top of the prior image:
Note that the mask is well away from the problematic area with the fringe. When I use the mask as a mask instead of drawing it, I get the final, perfect result:
Here's the code that draws the perfect version:
private func goodVersion() {
let center = CGPoint(x: view.bounds.width / 2, y: view.bounds.height / 2)
let radius: CGFloat = 100
let ringWidth: CGFloat = 44
let slop: CGFloat = 10
let disc = CAShapeLayer()
disc.frame = view.bounds
disc.fillColor = UIColor.red.cgColor
disc.strokeColor = nil
let ringPath = CGMutablePath()
ringPath.addArc(center: center, radius: radius + ringWidth / 2 + slop, startAngle: 0, endAngle: 2 * .pi, clockwise: true)
ringPath.closeSubpath()
disc.path = ringPath
view.layer.addSublayer(disc)
let wedge = CAShapeLayer()
wedge.frame = view.bounds
wedge.fillColor = UIColor.darkGray.cgColor
wedge.strokeColor = nil
let wedgePath = CGMutablePath()
wedgePath.move(to: center)
wedgePath.addArc(center: center, radius: radius + ringWidth / 2 + slop, startAngle: 0.1, endAngle: 0.6, clockwise: false)
wedgePath.closeSubpath()
wedge.path = wedgePath
view.layer.addSublayer(wedge)
let mask = CAShapeLayer()
mask.frame = view.bounds
mask.fillColor = nil
mask.strokeColor = UIColor.white.cgColor
mask.lineWidth = ringWidth
let maskPath = CGMutablePath()
maskPath.addArc(center: center, radius: radius, startAngle: 0, endAngle: 2 * .pi, clockwise: true)
maskPath.closeSubpath()
mask.path = maskPath
view.layer.mask = mask
}
Note that the mask applies to everything in view, so (in your case) you may need to move all of your layers into a subview has no other contents so it's safe to mask.
UPDATE
Looking at your playground, the problem is (still) that you're drawing two shapes that have exactly the same partially-transparent edge on top of each other. You can't do that. The solution is to draw the colored shapes larger, so that they are both completely opaque at the edge of the donut, and then use the layer mask to clip them to the donut shape.
I fixed your playground. Notice how in my version, the lineWidth of each colored section is donutThickness + 10, and the mask's lineWidth is only donutThickness. Here's the result:
Here's the playground:
import UIKit
import PlaygroundSupport
class ABDonutChart: UIView {
struct Datum {
var value: Double
var color: UIColor
}
var donutThickness: CGFloat = 20 { didSet { setNeedsLayout() } }
var separatorValue: Double = 1 { didSet { setNeedsLayout() } }
var separatorColor: UIColor = .white { didSet { setNeedsLayout() } }
var data = [Datum]() { didSet { setNeedsLayout() } }
func withAnimation(_ wantAnimation: Bool, do body: () -> ()) {
let priorFlag = wantAnimation
self.wantAnimation = true
defer { self.wantAnimation = priorFlag }
body()
layoutIfNeeded()
}
override func layoutSubviews() {
super.layoutSubviews()
let bounds = self.bounds
let center = CGPoint(x: bounds.origin.x + bounds.size.width / 2, y: bounds.origin.y + bounds.size.height / 2)
let radius = (min(bounds.size.width, bounds.size.height) - donutThickness) / 2
let maskLayer = layer.mask as? CAShapeLayer ?? CAShapeLayer()
maskLayer.frame = bounds
maskLayer.fillColor = nil
maskLayer.strokeColor = UIColor.white.cgColor
maskLayer.lineWidth = donutThickness
maskLayer.path = CGPath(ellipseIn: CGRect(x: center.x - radius, y: center.y - radius, width: 2 * radius, height: 2 * radius), transform: nil)
layer.mask = maskLayer
var spareLayers = segmentLayers
segmentLayers.removeAll()
let finalSum = data.reduce(Double(0)) { $0 + $1.value + separatorValue }
var runningSum: Double = 0
let animation = CABasicAnimation(keyPath: "strokeEnd")
animation.fromValue = 0.0
animation.toValue = 1.0
animation.duration = 2
animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
func addSegmentLayer(color: UIColor, segmentSum: Double) {
let angleOffset: CGFloat = -0.25 * 2 * .pi
let segmentLayer = spareLayers.popLast() ?? CAShapeLayer()
segmentLayer.strokeColor = color.cgColor
segmentLayer.lineWidth = donutThickness + 10
segmentLayer.lineCap = kCALineCapButt
segmentLayer.fillColor = nil
let path = CGMutablePath()
path.addArc(center: center, radius: radius, startAngle: angleOffset, endAngle: CGFloat(segmentSum / finalSum * 2 * .pi) + angleOffset, clockwise: false)
segmentLayer.path = path
layer.insertSublayer(segmentLayer, at: 0)
segmentLayers.append(segmentLayer)
if wantAnimation {
segmentLayer.add(animation, forKey: animation.keyPath)
}
}
for datum in data {
addSegmentLayer(color: separatorColor, segmentSum: runningSum + separatorValue / 2)
runningSum += datum.value + separatorValue
addSegmentLayer(color: datum.color, segmentSum: runningSum - separatorValue / 2)
}
addSegmentLayer(color: separatorColor, segmentSum: finalSum)
spareLayers.forEach { $0.removeFromSuperlayer() }
}
private var segmentLayers = [CAShapeLayer]()
private var wantAnimation = false
}
let container = UIView()
container.frame.size = CGSize(width: 300, height: 300)
container.backgroundColor = .black
PlaygroundPage.current.liveView = container
PlaygroundPage.current.needsIndefiniteExecution = true
let m = ABDonutChart(frame: CGRect(x: 0, y: 0, width: 215, height: 215))
m.center = CGPoint(x: container.bounds.size.width / 2, y: container.bounds.size.height / 2)
container.addSubview(m)
m.withAnimation(true) {
m.data = [
.init(value: 10, color: .red),
.init(value: 30, color: .blue),
.init(value: 15, color: .orange),
.init(value: 40, color: .yellow),
.init(value: 50, color: .green)]
}
To me, it looks like the edges are antialiased resulting in somewhat transparent pixels. The orange of the background can then be seen through the 'blurred' edges of the overlay.
Have you tried making the overlaid layers opaque?
layer.Opaque = true; //C#
An alternative way may be to draw a thin circle with the background color on top the orange edges. This should work, but it's not the prettiest method.
I currently have an image view that contains a circular image.
I've set it up like so:
profileImageView.layer.cornerRadius = self.profileImageView.frame.size.width / 2
profileImageView.clipsToBounds = true
I'm attempting to draw an arc around the circle using UIBezierPath, and I would like to pass the radius of the Image View for the radius parameter.
let circlePath = UIBezierPath(arcCenter: CGPoint(x: profileImageView.frame.size.width/2, y: profileImageView.frame.size.height/2), radius: IMG_VIEW_RADIUS, startAngle: CGFloat(0), endAngle:CGFloat(M_PI * 2), clockwise: true)
How would I go about doing that?
Swift 3.0
Another way
I just added a imageView like this
let imageView = UIImageView(frame: CGRect(x: 100, y: 100, width: 200, height: 200))
imageView.backgroundColor = UIColor.green
imageView.layer.cornerRadius = imageView.frame.size.width / 2
imageView.clipsToBounds = true
self.view.addSubview(imageView)
Doing the circular bezier path
let circlePath = UIBezierPath(arcCenter: CGPoint(x: imageView.frame.size.width/2,y: imageView.frame.size.height/2), radius: CGFloat((imageView.frame.size.width/2) - 3.5), startAngle: CGFloat(0), endAngle:CGFloat(M_PI * 2), clockwise: true)
let shapeLayer = CAShapeLayer()
shapeLayer.path = circlePath.cgPath
//fill color
shapeLayer.fillColor = UIColor.clear.cgColor
//stroke color
shapeLayer.strokeColor = UIColor.white.cgColor
//line width
shapeLayer.lineWidth = 2.0
//finally adding the shapeLayer to imageView's layer
imageView.layer.addSublayer(shapeLayer)
Now creating an outside border using the same concept
let outerCirclePath = UIBezierPath(arcCenter: CGPoint(x: imageView.frame.size.width/2,y: imageView.frame.size.height/2), radius: CGFloat(imageView.frame.size.width/2 ), startAngle: CGFloat(0), endAngle:CGFloat(M_PI * 2), clockwise: true)
let outerLayer = CAShapeLayer()
outerLayer.path = outerCirclePath.cgPath
//fill color
outerLayer.fillColor = UIColor.clear.cgColor
//stroke color
outerLayer.strokeColor = UIColor.blue.cgColor
//line width
outerLayer.lineWidth = 15.0
imageView.layer.addSublayer(outerLayer)
Now change the zPosition of shape layer created for the inner layer as the radius of this is smaller than the outer layer and it should be added at the top in order to be visible
shapeLayer.zPosition = 2
You need to tweak a bit with the radius of the first inner layer. In my case I just subtracted the radius with 3.5
just use border width and border color
profileImageView?.layer.cornerRadius = 5.0
profileImageView?.layer.borderColor = UIColor.white.cgColor