shadow not behind text - swift

I've made a function that is called in drawRect() inside a seperate made class for a Label. However, this draws only behind the text, and not behind the background of the label. I want to have a shadow behind the background of the label, not the text. How can I fix this? The same happens in a seperate made class for a View.
let COLOR_SHADOW_COLOR: CGColor = UIColor.gray.cgColor
let COLOR_SHADOW_OFFSET = CGSize(width: 2, height: -2)
let COLOR_SHADOW_RADIUS: CGFloat = 5
let COLOR_SHADOW_OPACITY: Float = 1.0
func setShadow(on object: UIView) {
object.layer.shadowColor = COLOR_SHADOW_COLOR
object.layer.shadowOpacity = COLOR_SHADOW_OPACITY
object.layer.shadowOffset = COLOR_SHADOW_OFFSET
object.layer.shadowRadius = COLOR_SHADOW_RADIUS
}

Fixed my own problem. The background was the same color as the text, but with a lower opacity. Xcode thinks that it should draw around text then. After using the pipet on the same color, it did made the shadow behind the label and view

Related

Rotating UIControl with CAGradientLayer not updating correctly Swift

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)
}
}

Add UIView (from xib) with transparency to SceneKit

I'm trying to load a UIView into SceneKit with a translucent background, but currently, it just fades to white as I decrease the opacity.
I have a very simple UIView layout in a .xib file that I want to load into SceneKit.
So far I can display the UIView in the SCNMaterial, change any text fields, images, etc inside the view without a problem. However, I cannot let it have transparency. If I change the alpha of the view it just fades to white.
most of the code is the below:
if let cardView = Bundle.main.loadNibNamed("OverlayCard", owner: self, options: nil)?.first as? OverlayCard {
cardView.backgroundColor = UIColor(displayP3Red: 1.0, green: 0.4, blue: 0.9, alpha: 0.2)
let newplane = SCNPlane()
let newMaterial = SCNMaterial()
cardView.alpha = 0.2
cardView.isOpaque = false
newMaterial.diffuse.contents = cardView
newMaterial.blendMode = .add
newplane.materials = [newMaterial]
let viewNode = SCNNode(geometry: newplane)
self.addChildNode(viewNode)
}
I've left in various things like assigning the blendMode, backgroundColor with 0.2 opacity as well as the entire view because these are all things I've tried but still get a white background with some of the view's elements on top of the white very faded out. Have also tried blendMode = .alpha to find no difference.
'self' here is a subclass of SCNNode.
Does anyone know how I can make this view's background fade to transparent, rather than fade to white? Or, another way to load a view into SceneKit.
Try setting the layer of the view as diffuse.contents instead of the view itself.
newMaterial.diffuse.contents = cardView.layer

Vertically aligning text in an NSTextField using Swift

I have been reading through the various options on how to set the vertical alignment on an NSTextField. I want the text to be displayed in the center and to do it programatically in Swift. Here are the things I have looked so far:
http://www.cocoabuilder.com/archive/cocoa/174994-repositioning-an-nstextfieldcell.html
https://red-sweater.com/blog/148/what-a-difference-a-cell-makes
Vertically Centre Text in NSSecureTextField with subclassing
Get NSTextField contents to scale
vertically align text in a CATextLayer?
One thing I have tried in Swift is to set the following property:
textField.usesSingleLineMode = true
Any tips on the best way to vertically center text would be much appreciated!
This is very hard to do, as Apple makes this very difficult. I achieved it by subclassing NSTextFieldCell and overriding the drawingRectForBounds: method like so:
override func drawingRectForBounds(theRect: NSRect) -> NSRect {
let newRect = NSRect(x: 0, y: (theRect.size.height - 22) / 2, width: theRect.size.width, height: 22)
return super.drawingRectForBounds(newRect)
}
This is just my way to do it, I'm sure there are better ways, which I don't know (yet). And this only works for the standard font size in TextFields (which gives a text height of 22). That's why I hardcoded that. Haven't figured out yet, how to get the height in the cell if you change the font.
Result:
Try this on a playground, it centers the text perfectly, use it on your projects! Hope it helps!
import Cocoa
let cell = NSTableCellView()
cell.frame = NSRect(x: 0, y: 0, width: 100, height: 100)
let tf = NSTextField()
tf.frame = cell.frame
tf.stringValue = "MyTextfield"
tf.alignment = .Center
let stringHeight: CGFloat = tf.attributedStringValue.size().height
let frame = tf.frame
var titleRect: NSRect = tf.cell!.titleRectForBounds(frame)
titleRect.size.height = stringHeight + ( stringHeight - (tf.font!.ascender + tf.font!.descender ) )
titleRect.origin.y = frame.size.height / 2 - tf.lastBaselineOffsetFromBottom - tf.font!.xHeight / 2
tf.frame = titleRect
cell.addSubview(tf)
I have added the NSTextField inside a NSView and centered it.
Another solution was (in an iOS project) to create a UILabel and allow it adjust its size (sizeToFit()) and again embed it inside a UIView.
I personally don't like the calculations in previous answers and the second solution for iOS works for all texts size and row numbers.
I was also facing vertical alignment issue with NSTextField. My requirement involved, rendering a single-line string inside a NSTextField. Additionally,
textfield needed to be resize implying we had programatically resized the font-point-size of the text inside text-field on resize. In this scenario we faced vertical-alignment issues - the mis-alignment was tough to grasp/understand in a straight forward way.
What finally worked:
So, in my scenario a simple,
turn off the "Single Line Mode" in interface builder
for the text-field solved the issue.
The accepted answer works perfectly and here's the Swift3 version.
class VerticallyAlignedTextFieldCell: NSTextFieldCell {
override func drawingRect(forBounds rect: NSRect) -> NSRect {
let newRect = NSRect(x: 0, y: (rect.size.height - 22) / 2, width: rect.size.width, height: 22)
return super.drawingRect(forBounds: newRect)
}
}

Borders not covering background

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

Layering transparent images and text on top of a mapView (Swift)

I want to put a transparent box on top of a mapView and then some text on top of that.
I can do this treating the image as a button and altering the alpha setting but only the last UILabel I put in place remains black, the rest are muted.
Is this possible with Tags or something or does it have to be done programatically?
Anyway after a couple of hours sleuthing this is a working solution.
Declare your layer
#IBOutlet weak var layerView: UIView!
var myLayer: CALayer {
return layerView.layer
}
Put a UIView on your ViewController and link it to layerView.
Create a method/func to display the frame, e.g.
func displayMyFrame() {
myLayer.frame = CGRectMake(100, 100, 200, 40)
myLayer.backgroundColor = UIColor.whiteColor().CGColor
myLayer.borderWidth = 1.0
myLayer.borderColor = UIColor.redColor().CGColor
myLayer.shadowOpacity = 0.6
myLayer.cornerRadius = 5.0
myLayer.shadowRadius = 10.0
myLayer.opacity = 0.6
}
Put your UILabels on the view and change their tags to 1 (in this example).
Call the func in viewDidLoad.
displayMyFrame()
view.layer.insertSublayer(myLayer, atIndex: 1)
The atIndex: 1 means that this frame will be put behind the UILabels with a Tag of 1.
This works, hope that it helps.