I want to clip the bounds of my UIView perfectly to interact as a circle, but however I set the corner radius, mask and clip to bounds and it shows correctly, it moves as a square, as you can see in the image:
The code I have used is:
let bubble1 = UIView(frame: CGRectMake(location.x, location.y, 128, 128))
bubble1.backgroundColor = color2
bubble1.layer.cornerRadius = bubble1.frame.size.width/2
bubble1.clipsToBounds = true
bubble1.layer.masksToBounds = true
What is wrong there that does still keeping the edges of the view?
PD: All the views moves dynamically, so when it moves and hit each other, it shows these empty space, acting as an square instead of as an circle
Finally, after all I found what to implement, and was just that class instead of UIView:
class SphereView: UIView {
// iOS 9 specific
override var collisionBoundsType: UIDynamicItemCollisionBoundsType {
return .Ellipse
}
}
Seen here: https://objectcoder.com/2016/02/29/variation-on-dropit-demo-from-lecture-12-dynamic-animation-cs193p-stanford-university/
Related
I am using a CAShapeLayer with UIBezierPath to make a circular progress bar. The code requires a center value based on a CGPoint.
let circleLayer = CAShapeLayer()
let circlePath = UIBezierPath(arcCenter: center, radius: 100, startAngle: -CGFloat.pi / 2, endAngle: 2 * CGFloat.pi, clockwise: true)
I have set the value manually as follows:
let center = CGPoint(x: 70, y: 70)
However those values are relative to the superView and I need to make it relative to its parent UIView.
All other elements in the UIView are constrained using programmatic UI code like this:
sampleText.translatesAutoresizingMaskIntoConstraints = false
sampleText.topAnchor.constraint(equalTo: directionsTitle.bottomAnchor, constant: 0).isActive = true
sampleText.leadingAnchor.constraint(equalTo: timerFooter.leadingAnchor, constant: 8).isActive = true
sampleText.trailingAnchor.constraint(equalTo: timerFooter.trailingAnchor, constant: -8).isActive = true
Fixed values may work fine on one device but will be out of alignment on a larger or smaller device. My question is, how do I determine the values for center of the UIView that will meet the values required of CGPoint?
I have tried this:
let centerX = view.centerXAnchor
let centerY = view.centerYAnchor
let center = CGPoint(x: centerX, y: centerY)
However, that throws an error: No exact matches in call to initializer
The following image reflects where the shape placement is relative to. The blue box indicates the desired UIView area where I want to position the circle.
Advice from wiser minds would be greatly appreciated.
Ah, ok, I think I understand what the problem is that you're facing.
I think your issue is that you're trying to use the CAShapeLayer like it is a UIView. When in reality they don't behave like that at all.
What you should be doing is creating a UIView subclass and putting the CAShapeLayer in there. Now you only need to worry about how the CAShapeLayer fits into its own UIView subclass.
To "position the layer" into some other view you actually don't need to worry about that at all. You just place the new UIView subclass and the layer will go along with it.
e.g.
class MyProgressView: UIView {
let circleLayer: CAShapeLayer
// add the circleLayer
// add properties for customising the circle layer
// Position the circle layer in the centre of the MyProgressView frame
// I'd suggest using `layoutSubviews` or something for this.
// etc...
}
Now... to position your "CircleLayer" you actually don't need to. You just position the MyProgressView where you want it to be and the layer is part of that so will go along for the ride.
From your screenshot it looks like you want the view with the blue rectangle to contain the circleLayer. If that is the case then make the blue rectangle view your custom UIView subclass and ... done. It will now contain the circle view.
RayWenderlich has some good stuff about customising views with CALayer... https://www.raywenderlich.com/10317653-calayer-tutorial-for-ios-getting-started#toc-anchor-002
It sounds like you want the midpoint of the UIView's bounds I think that's yourView.bounds.midX and yourView.bounds.midY
A view's bounds is its own coordinate space. A view's frame is its location in its parent space.
UIView has methods like convertPoint:toCoordinateSpace: and friends for converting points and rects between those spaces.
Rather than using a normal button, I subclassed a UIControl because I needed to add a gradient to it. I also have a way to add a shadow and an activity indicator (not visible in the image below) as a stateful button to stop users hammering the button if (for example) an API call is being made.
It was really tricky to try to get the UIControl to rotate, and to be able to do this I added the shadow as a separate view to a container view containing the UIControl so a shadow could be added.
Now the issue is the control does not behave quite like a view on rotation - let me show you a screen grab for context:
This is mid-rotation but is just about visible to the eye - the image shows that the Gradient is 75% of the length of a blue UIView in the image.
https://github.com/stevencurtis/statefulbutton
In order to perform this rotation I remove the shadowview and then change the frame of the gradient frame to its bounds, and this is the problem.
func viewRotated() {
CATransaction.setDisableActions(true)
shadowView!.removeFromSuperview()
shadowView!.frame = self.frame
shadowView!.layer.masksToBounds = false
shadowView!.layer.shadowOffset = CGSize(width: 0, height: 3)
shadowView!.layer.shadowRadius = 3
shadowView!.layer.shadowOpacity = 0.3
shadowView!.layer.shadowPath = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: .allCorners, cornerRadii: CGSize(width: 20, height: 20)).cgPath
shadowView!.layer.shouldRasterize = true
shadowView!.layer.rasterizationScale = UIScreen.main.scale
self.gradientViewLayer.frame = self.bounds
self.selectedViewLayer.frame = self.bounds
CATransaction.commit()
self.insertSubview(shadowView!, at: 0)
}
So this rotation method is called through the parent view controller:
override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
super.viewWillTransition(to: size, with: coordinator)
coordinator.animate(alongsideTransition: { context in
context.viewController(forKey: UITransitionContextViewControllerKey.from)
//inform the loginButton that it is being rotated
self.loginButton.viewRotated()
}, completion: { context in
// can call here when completed the transition
})
}
I know this is the problem, and I guess it is not happening at quite the right time to act the same way as a UIView. Now the issue is that I have tried many things to get this to work, and my best solution (above) is not quite there.
It isn't helpful to suggest to use a UIButton, to use an image for the gradient (please don't suggest using a gradient image as a background for a UIButton, I've tried this) or a third party library. This is my work, it functions but does not work acceptably to me and I want to get it to work as well as a usual view (or at least know why not). I have tried the other solutions above as well, and have gone for my own UIControl. I know I can lock the view if there is an API call, or use other ways to stop the user pressing the button too many times. I'm trying to fix my solution, not invent ways of getting around this issue with CAGradientLayer.
The problem: I need to make a UIControlView with a CAGradientLayer as a background rotate in the same way as a UIView, and not exhibit the issue shown in the image above.
Full Example:
https://github.com/stevencurtis/statefulbutton
Here is working code:
https://gist.github.com/alldne/22d340b36613ae5870b3472fa1c64654
These are my recommendations to your code:
1. A proper place for setting size and the position of sublayers
The size of a view, namely your button, is determined after the layout is done. What you should do is just to set the proper size of sublayers after the layout. So I recommend you to set the size and position of the gradient sublayers in layoutSubviews.
override func layoutSubviews() {
super.layoutSubviews()
let center = CGPoint(x: self.bounds.width / 2, y: self.bounds.height / 2)
selectedViewLayer.bounds = self.bounds
selectedViewLayer.position = center
gradientViewLayer.bounds = self.bounds
gradientViewLayer.position = center
}
2. You don’t need to use an extra view to draw shadow
Remove shadowView and just set the layer properties:
layer.shadowOffset = CGSize(width: 0, height: 3)
layer.shadowRadius = 3
layer.shadowOpacity = 0.3
layer.shadowColor = UIColor.black.cgColor
clipsToBounds = false
If you have to use an extra view to draw shadow, then you can add the view once in init() and set the proper size and position in layoutSubviews or you can just programmatically set auto layout constraints to the superview.
3. Animation duration & timing function
After setting proper sizes, your animation of the gradient layers and the container view doesn’t sync well.
It seems that:
During the rotation transition, coordinator(UIViewControllerTransitionCoordinator) has its own transition duration and easing function.
And the duration and easing function are applied automatically to all the subviews (UIView).
However, those values are not applied to the CALayer without an associated UIView. Consequently, it uses the default timing function and duration of CoreAnimation.
To sync the animations, explicitly set the animation duration and the timing function like below:
class ViewController: UIViewController {
...
override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
super.viewWillTransition(to: size, with: coordinator)
CATransaction.setAnimationDuration(coordinator.transitionDuration)
CATransaction.setAnimationTimingFunction(coordinator.completionCurve.timingFunction)
}
...
}
// Swift 4
extension UIView.AnimationCurve {
var timingFunction: CAMediaTimingFunction {
let functionName: CAMediaTimingFunctionName
switch self {
case .easeIn:
functionName = kCAMediaTimingFunctionEaseIn as CAMediaTimingFunctionName
case .easeInOut:
functionName = kCAMediaTimingFunctionEaseInEaseOut as CAMediaTimingFunctionName
case .easeOut:
functionName = kCAMediaTimingFunctionEaseOut as CAMediaTimingFunctionName
case .linear:
functionName = kCAMediaTimingFunctionLinear as CAMediaTimingFunctionName
}
return CAMediaTimingFunction(name: functionName as String)
}
}
Is there a way to make the corner radius of a UIView adept to the view it belongs to? I'm not comfortable with the idea of hard-coding corner radius values, because as soon as the width or the height of your view changes (on different screen orientations for example), the corners will look totally different. For example, take a look at WhatsApp's chat window.
As you can see, every message container view has a different width and a different height, but the curve of the corners are all exactly the same. This is what I'm trying to achieve. I want the curves of my corners to be the same on every view, no matter what the size of the view is or what screen the view is displayed on. I've tried setting the corner radius relative to the view's height (view.layer.cornerRadius = view.frame.size.height * 0.25) and I've also tried setting it to the view's width, but this doesn't work. The corners still look weird as soon as they are displayed on a different screen size. Please let me know if there's a certain formula or trick to make the curves look the same on every view/screen size.
Here's the best I can do. I don't know if this will be of help, but hopefully it will give you some ideas.
First the code:
class ViewController: UIViewController {
let cornerRadius:CGFloat = 10
let insetValue:CGFloat = 10
var numberOfViews:Int = 0
var myViews = [UIView]()
override func viewDidLoad() {
super.viewDidLoad()
view.translatesAutoresizingMaskIntoConstraints = false
}
override func viewWillLayoutSubviews() {
setNumberOfViews()
createViews()
createViewHierarchy()
addConstraints()
}
func setNumberOfViews() {
var smallerDimension:CGFloat = 0
if view.frame.height < view.frame.width {
smallerDimension = view.frame.height
} else {
smallerDimension = view.frame.width
}
let viewCount = smallerDimension / (insetValue * 2)
numberOfViews = Int(viewCount)
}
func createViews() {
for i in 1...numberOfViews {
switch i % 5 {
case 0:
myViews.append(MyView(UIColor.black, cornerRadius))
case 1:
myViews.append(MyView(UIColor.blue, cornerRadius))
case 2:
myViews.append(MyView(UIColor.red, cornerRadius))
case 3:
myViews.append(MyView(UIColor.yellow, cornerRadius))
case 4:
myViews.append(MyView(UIColor.green, cornerRadius))
default:
break
}
}
}
func createViewHierarchy() {
view.addSubview(myViews[0])
for i in 1...myViews.count-1 {
myViews[i-1].addSubview(myViews[i])
}
}
func addConstraints() {
for view in myViews {
view.topAnchor.constraint(equalTo: (view.superview?.topAnchor)!, constant: insetValue).isActive = true
view.leadingAnchor.constraint(equalTo: (view.superview?.leadingAnchor)!, constant: insetValue).isActive = true
view.trailingAnchor.constraint(equalTo: (view.superview?.trailingAnchor)!, constant: -insetValue).isActive = true
view.bottomAnchor.constraint(equalTo: (view.superview?.bottomAnchor)!, constant: -insetValue).isActive = true
}
}
}
class MyView: UIView {
convenience init(_ backgroundColor:UIColor, _ cornerRadius:CGFloat) {
self.init(frame: CGRect.zero)
self.translatesAutoresizingMaskIntoConstraints = false
self.backgroundColor = backgroundColor
self.layer.cornerRadius = cornerRadius
}
}
Explanation:
This is fairly simple code. The intent was to create as deeply nested a view hierarchy as possible, and, using auto layout, have two main variables: cornerRadius (the view's corner radius) and insetValue (the "frame's" inset). These two variables can be adjusted for experimenting.
The bulk of the logic is in viewWillLayoutSubviews, where the root view frame size is know. Since I'm using 5 different background colors, I'm calculating how many views can fit in the hierarchy. Then I'm creating them, followed by creating the view hierarchy, and finally I'm adding the constraints.
Experimenting and conclusions:
I was able to see what your concern is - yes, if a view's size components are smaller than the corner radius, you end up with inconsistent looking corners. But these values are pretty small - pretty much 10 or less. Most views are unusable at that size. (If I recall even the HIG suggests that a button should be no less than 40 points in size. Sure, even Apple breaks that rule. Still.)
If your 'insetValueis sufficiently larger than the corner radius, you should never have an issue. Likewise, using the iMessage scenario, a singleUILabelcontaining text and/or emoticons should have enough height that a noticeablecornerRadius` can be had.
The key point to set things like cornerRadius and insetValue is in viewWillLayoutSubviews, when you can decide (1) which is the smaller dimension, height or width, (2) how deeply you can nest views, and (3) how large of a corner radius you can set.
Use auto layout! Please note the absolute lack of frames. Other than determining the root view's dimensions at the appropriate time, you can write very compact code without worrying about device size or orientation.
I've got a UILabel is using a border the same color as a background which it is half obscuring, to create a nice visual effect. However the problem is that there is still a tiny, yet noticeable, sliver of the label's background color on the OUTSIDE of the border.
The border is not covering the whole label!
Changing the border width doesn't change anything either, sadly.
Here's a picture of what's going on, enlarged so you can see it:
And my code follows:
iconLbl.frame = CGRectMake(theWidth/2-20, bottomView.frame.minY-20, 40, 40)
iconLbl.font = UIFont.fontAwesomeOfSize(23)
iconLbl.text = String.fontAwesomeIconWithName(.Info)
iconLbl.layer.masksToBounds = true
iconLbl.layer.cornerRadius = iconLbl.frame.size.width/2
iconLbl.layer.borderWidth = 5
iconLbl.layer.borderColor = topBackgroundColor.CGColor
iconLbl.backgroundColor = UIColor.cyanColor()
iconLbl.textColor = UIColor.whiteColor()
Is there something I'm missing?
Or am I going to have to figure out another to achieve this effect?
Thanks!
EDIT:
List of things I've tried so far!
Changing layer.borderWidth
Fussing around with clipsToBounds/MasksToBounds
Playing around the the layer.frame
Playing around with an integral frame
EDIT 2:
No fix was found! I used a workaround by extending this method on to my UIViewController
func makeFakeBorder(inputView:UIView,width:CGFloat,color:UIColor) -> UIView {
let fakeBorder = UIView()
fakeBorder.frame = CGRectMake(inputView.frame.origin.x-width, inputView.frame.origin.y-width, inputView.frame.size.width+width*2, inputView.frame.size.height+width*2)
fakeBorder.backgroundColor = color
fakeBorder.clipsToBounds = true
fakeBorder.layer.cornerRadius = fakeBorder.frame.size.width/2
fakeBorder.addSubview(inputView)
inputView.center = CGPointMake(fakeBorder.frame.size.width/2, fakeBorder.frame.size.height/2)
return fakeBorder
}
I believe this is the way a border is drawn to a layer in iOS. In the document it says:
When this value is greater than 0.0, the layer draws a border using the current borderColor value. The border is drawn inset from the receiver’s bounds by the value specified in this property. It is composited above the receiver’s contents and sublayers and includes the effects of the cornerRadius property.
One way to fix this is to apply a mask to a view's layer, but I found out that even if so we still can see a teeny tiny line around the view when doing snapshot tests. So to fix it more, I put this code to layoutSubviews
class MyView: UIView {
override func layoutSubviews() {
super.layoutSubviews()
let maskInset: CGFloat = 1
// Extends the layer's frame.
layer.frame = layer.frame.inset(dx: -maskInset, dy: -maskInset)
// Increase the border width
layer.borderWidth = layer.borderWidth + maskInset
layer.cornerRadius = bounds.height / 2
layer.maskToBounds = true
// Create a circle shape layer with true bounds.
let mask = CAShapeLayer()
mask.path = UIBezierPath(ovalIn: bounds.inset(dx: maskInset, dy: maskInset)).cgPath
layer.mask = mask
}
}
CALayer's mask
I've been struggling for a view hours to figure out how to get my view masked by a shape that is in another view. Basically I have a circular countdown timer that I want to be masked out by an animating circle that scales up from the center of the timer when the timer is reset.
I tried setting timerMask.maskView = timerCircleGrahics where timerCircleGraphics is the name of my timer animation view. But this is giving me very strange results when I test the app. It seems to clip the view to the rectangle bounds of my mask view rather than the alpha of the bounds that are drawn within that view. The mask layer is centered and being drawn properly, but I've never attempted this before so am not sure if I am doing it right.
Here is the class for my mask shape:
class timerBackgroundMask: UIView {
override func drawRect(rect: CGRect) {
var ovalPath = UIBezierPath(ovalInRect: CGRectMake(0, 0, 238, 238))
colorGreen.setFill()
ovalPath.fill()
}
}
Then using IB, I assign this mask to a manually placed View in my Storyboard called timerMask. I am realizeing now that by assigning timerBackgroundMask class to timerMask I have programatically added a subview to my manually placed Storyboard view, but I feel like the alpha should come through just the same when set this view to mask out anotherview. Here is the code i use to set the mask
timerCircleGraphics.layer.mask = timerMask.layer
The result I am getting is pretty weird:
The red portion should be a circle that is partially clipped by my timerMask from the center outward. The light green circle that you see is simply the background view of the counter, however it happens to be the exact position and size as my timerBackgroundMask for reference.
Don't bother creating a class and using the Storyboard. Do it straight in code, the simple way:
var ovalPath = UIBezierPath(ovalInRect: CGRectMake(0, 0, 238, 238))
colorGreen.setFill()
ovalPath.fill()
var mask = CAShapeLayer()
mask.path = ovalPath.CGPath
timerCircleGraphics.layer.mask = mask