I am trying to get random CGPoints along the 'outer contour' of UIView so that I will be able to draw UIBezierPath line over obtained CGPoints. For example, get CGPoints from below red dots which I marked myself by hand. Any idea?
###Edit###
As per Sweeper's advice I am trying to add CAShapeLayer into my custom view but it returns nil when I am printing its path. Please could you point out what I am missing?
class ViewController: UIViewController {
let shapeLayer = CAShapeLayer()
override func viewDidLoad() {
super.viewDidLoad()
let view = BubbleView(frame: CGRect(x: self.view.frame.midX / 2, y: self.view.frame.midY/2, width: 150, height: 100))
view.backgroundColor = .gray
view.layer.cornerRadius = 30
self.view.addSubview(view)
}
}
class BubbleView: UIView {
var pathLayer: CAShapeLayer!
override func layoutSubviews() {
pathLayer = CAShapeLayer()
pathLayer.bounds = frame
self.layer.addSublayer(pathLayer)
print(pathLayer.path) // returns nil
}
override init(frame: CGRect) {
super.init(frame: frame)
backgroundColor = .clear
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
Related
I feel this is pretty simple to accomplish but I can't seem to figure it out. I'm fairly new to not using the storyboard and trying to learn how to set my constraints programatically for my views. I created the view that I want easily in storyboard but can't seem to get it programatically.
I have my view controller has my parent view, and then I call a container view. I imagine in the container view is where I setup my constraints but I can't get the height of my view to stay the same every-time I change to a different device
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
var clariView = ClariContainerView()
view.addSubview(clariView)
}
}
This my view controller and then my ClariContainerView looks like this:
class ClariContainerView: UIView {
lazy var clariQuestionView: UIView = {
let containerView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 0))
containerView.backgroundColor = .blue
containerView.translatesAutoresizingMaskIntoConstraints = false
return containerView
}()
override init(frame: CGRect) {
super.init(frame: frame)
setupView()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
setupView()
}
public func setupView() {
addSubview(clariQuestionView)
setupLayout()
}
public func setupLayout() {
NSLayoutConstraint.activate([
clariQuestionView.heightAnchor.constraint(equalToConstant: 169)
])
}
}
What I'm trying to recreate is this:
I need the height of the blue view to always be 169.
Here is how you would do that:
First, you don't need to define a frame for your containerView since the translatesAutoresizingMaskIntoConstraints = falsestatement is specifying that you'll be using auto-layout and therefore the frame will be ignored:
lazy var clariQuestionView: UIView = {
let containerView = UIView()
containerView.backgroundColor = .blue
containerView.translatesAutoresizingMaskIntoConstraints = false
return containerView
}()
And here is how you would define your constraints. You need to set height, but also need to pin the view to the bottom, the leading, and the trailing edges of self.view:
public func setupLayout() {
NSLayoutConstraint.activate([
clariQuestionView.heightAnchor.constraint(equalToConstant: 169),
clariQuestionView.bottomAnchor.constraint(equalTo: self.view.bottomAnchor),
clariQuestionView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor),
clariQuestionView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor)
])
}
For such a basic layout you don't really need to add heightAnchor. Here is a simple way to achieve desired behavior + bonus — a code snippet to adjust height according to the device's safeAreaInsets.
class ClariContainerView: UIView {
lazy var clariQuestionView: UIView = {
let desiredContainerHeigh = 169
// If you want, you can use commented code to adjust height according to the device's safe area.
// This might be needed if you want to keep the same height over safe area on all devices.
// let safeAreaAdjustment = UIApplication.shared.keyWindow?.rootViewController?.view.safeAreaInsets.bottom ?? 0
let containerView = UIView(frame: CGRect(x: 0, y: UIScreen.main.bounds.height - 169, width: UIScreen.main.bounds.width, height: 169))
containerView.backgroundColor = .blue
containerView.translatesAutoresizingMaskIntoConstraints = true
return containerView
}()
override init(frame: CGRect) {
super.init(frame: frame)
setupView()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
setupView()
}
public func setupView() {
addSubview(clariQuestionView)
}
}
I have a need for a simple QR Code class that I can re-use. I have created the class and it works, however manually setting the size constraints is not desired because it needs to adjust its size based on the DPI of the device. Here in this minimal example, I just use 100 as the sizing calculation code is not relevant (set to 50 in IB). Also I will have multiple QR Codes in different positions, which I will manage their positioning by IB. But at least I hope to be able to set the width and height constraints in code.
The below code shows a QR code, in the right size (set at runtime), but when the constraints are set to horizontally and vertically center it, it does not. Again, I don't want the size constraints in the IB, but I do want the position constraints in the IB
import Foundation
import UIKit
#IBDesignable class QrCodeView: UIImageView {
var content:String = "test" {
didSet {
generateCode(content)
}
}
lazy var filter = CIFilter(name: "CIQRCodeGenerator")
lazy var imageView = UIImageView()
override init(frame: CGRect) {
super.init(frame: frame)
setup()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
override func layoutSubviews() {
super.layoutSubviews()
imageView.frame = CGRect(x:0, y:0, width:100, height:100)
frame = CGRect(x:frame.origin.x, y:frame.origin.y, width:100, height:100)
}
func setup() {
//translatesAutoresizingMaskIntoConstraints = false
generateCode(content)
addSubview(imageView)
layoutIfNeeded()
}
func generateCode(_ string: String) {
guard let filter = filter,
let data = string.data(using: .isoLatin1, allowLossyConversion: false) else {
return
}
filter.setValue(data, forKey: "inputMessage")
guard let ciImage = filter.outputImage else {
return
}
let transform = CGAffineTransform(scaleX: 10, y: 10)
let scaled = UIImage(ciImage: ciImage.transformed(by: transform))
imageView.image = scaled
}
}
I believe you're making this more complicated than need be...
Let's start with a simple #IBDesignable UIImageView subclass.
Start with a new project and add this code:
#IBDesignable
class MyImageView: UIImageView {
// we'll use this later
var myIntrinsicSize: CGSize = CGSize(width: 100.0, height: 100.0)
override var intrinsicContentSize: CGSize {
return myIntrinsicSize
}
override init(frame: CGRect) {
super.init(frame: frame)
setup()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
override func prepareForInterfaceBuilder() {
super.prepareForInterfaceBuilder()
setup()
self.image = UIImage()
}
func setup() {
backgroundColor = .green
contentMode = .scaleToFill
}
}
Now, in Storyboard, add a UIImageView to a view controller. Set its custom class to MyImageView and set Horizontal and Vertical Center constraints.
The image view should automatically size itself to 100 x 100, centered in the view with a green background (we're just setting the background so we can see it):
Run the app, and you should see the same thing.
Now, add it as an #IBOutlet to a view controller:
class ViewController: UIViewController {
#IBOutlet var testImageView: MyImageView!
override func viewDidLoad() {
super.viewDidLoad()
testImageView.myIntrinsicSize = CGSize(width: 300.0, height: 300.0)
}
}
Run the app, and you will see a centered green image view, but now it will be 300 x 300 points instead of 100 x 100.
The rest of your task is pretty much adding code to set this custom class's .image property once you've rendered the QRCode image.
Here's the custom class:
#IBDesignable
class QRCodeView: UIImageView {
// so we can test changing the QRCode content in IB
#IBInspectable
var content:String = "test" {
didSet {
generateCode(content)
}
}
var qrIntrinsicSize: CGSize = CGSize(width: 100.0, height: 100.0)
override var intrinsicContentSize: CGSize {
return qrIntrinsicSize
}
lazy var filter = CIFilter(name: "CIQRCodeGenerator")
override init(frame: CGRect) {
super.init(frame: frame)
setup()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
override func prepareForInterfaceBuilder() {
super.prepareForInterfaceBuilder()
setup()
generateCode(content)
}
func setup() {
contentMode = .scaleToFill
}
override func layoutSubviews() {
super.layoutSubviews()
generateCode(content)
}
func generateCode(_ string: String) {
guard let filter = filter,
let data = string.data(using: .isoLatin1, allowLossyConversion: false) else {
return
}
filter.setValue(data, forKey: "inputMessage")
guard let ciImage = filter.outputImage else {
return
}
let scX = bounds.width / ciImage.extent.size.width
let scY = bounds.height / ciImage.extent.size.height
let transform = CGAffineTransform(scaleX: scX, y: scY)
let scaled = UIImage(ciImage: ciImage.transformed(by: transform))
self.image = scaled
}
}
In Storyboard / IB:
And here's an example view controller:
class ViewController: UIViewController {
#IBOutlet var qrCodeView: QRCodeView!
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
// calculate your needed size
// I'll assume it ended up being 240 x 240
qrCodeView.qrIntrinsicSize = CGSize(width: 240.0, height: 240.0)
}
}
Edit
Here's a modified QRCodeView class that will size itself to a (physical) 15x15 mm image.
I used DeviceKit from https://github.com/devicekit/DeviceKit to get the current device's ppi. See the comment to replace it with your own (assuming you are already using something else).
When this class is instantiated, it will:
get the current device's ppi
convert ppi to pixels-per-millimeter
calculate 15 x pixels-per-millimeter
convert based on screen scale
update its intrinsic size
The QRCodeView (subclass of UIImageView) needs only position constraints... so you can use Top + Leading, Top + Trailing, Center X & Y, Bottom + CenterX, etc, etc.
#IBDesignable
class QRCodeView: UIImageView {
#IBInspectable
var content:String = "test" {
didSet {
generateCode(content)
}
}
var qrIntrinsicSize: CGSize = CGSize(width: 100.0, height: 100.0)
override var intrinsicContentSize: CGSize {
return qrIntrinsicSize
}
lazy var filter = CIFilter(name: "CIQRCodeGenerator")
override init(frame: CGRect) {
super.init(frame: frame)
setup()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
override func prepareForInterfaceBuilder() {
super.prepareForInterfaceBuilder()
setup()
generateCode(content)
}
func setup() {
contentMode = .scaleToFill
// using DeviceKit from https://github.com/devicekit/DeviceKit
// replace with your lookup code that gets
// the device's ppi
let device = Device.current
guard let ppi = device.ppi else { return }
// convert to pixels-per-millimeter
let ppmm = CGFloat(ppi) / 25.4
// we want 15mm size
let mm15 = 15.0 * ppmm
// convert based on screen scale
let mmScale = mm15 / UIScreen.main.scale
// update our intrinsic size
self.qrIntrinsicSize = CGSize(width: mmScale, height: mmScale)
}
override func layoutSubviews() {
super.layoutSubviews()
generateCode(content)
}
func generateCode(_ string: String) {
guard let filter = filter,
let data = string.data(using: .isoLatin1, allowLossyConversion: false) else {
return
}
filter.setValue(data, forKey: "inputMessage")
guard let ciImage = filter.outputImage else {
return
}
let scX = bounds.width / ciImage.extent.size.width
let scY = bounds.height / ciImage.extent.size.height
let transform = CGAffineTransform(scaleX: scX, y: scY)
let scaled = UIImage(ciImage: ciImage.transformed(by: transform))
self.image = scaled
}
}
I have a small problem and not sure why it is not working. I have a code:
func rounded(cornerRadius: CGFloat? = nil) {
if let cornerRadius = cornerRadius {
layer.cornerRadius = cornerRadius
} else {
layer.cornerRadius = min(frame.size.height, frame.size.width) / 2
}
clipsToBounds = true
}
And I am trying to use like this:
cameraImageContainer.rounded()
cameraImageContainer = UIView
The image is not really very rounded and it doesn't look good.
Any Suggestions please?
Since the frame can change, it's easier to implement the corner radius when the bounds are set. Give this a try:
class CircleView: UIView {
override var bounds: CGRect {
didSet {
self.layer.cornerRadius = min(bounds.size.height, bounds.size.width) / 2
}
}
override init(frame: CGRect) {
super.init(frame: frame)
self.commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
self.commonInit()
}
private func commonInit() {
clipsToBounds = true
}
}
Call the function to round the image in viewDidApper like this
override func viewDidAppear(_ animated: Bool) {
cameraImageContainer.rounded()
}
because the frames of the button will be set only after the view is loaded
if you waant to call it in viewDidLoad create a custom class for imageView and set it in the storybaord
I'm currently trying to customize the UIPageControl so it will fit my needs. However I seem to be having a problem when implementing some logic in the draw
What I want to do is to be able to user IBInspectable variables to draw out the UIPageControl however those seem to still be nil when the draw method is being called and when I try to implement my logic in the awakeFromNib for instance it won't work.
What I did so far is the following
class BoardingPager: UIPageControl {
#IBInspectable var size: CGSize!
#IBInspectable var borderColor: UIColor!
#IBInspectable var borderWidth: CGFloat! = 1
override init(frame: CGRect) {
super.init(frame: frame)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
self.pageIndicatorTintColor = UIColor.clear
}
override func draw(_ rect: CGRect) {
super.draw(rect)
setDots()
}
func setDots() {
for i in (0..<self.numberOfPages) {
let dot = self.subviews[i]
if size != nil {
let dotFrame = CGRect(x: size.width/2, y: size.height/2, width: size.width, height: size.height)
dot.frame = dotFrame
}
if i != self.currentPage {
dot.layer.cornerRadius = dot.frame.size.height / 2
dot.layer.borderColor = borderColor.cgColor
dot.layer.borderWidth = borderWidth
}
}
}
}
Another problem I'm facing is that I want to remove/add a border when the current page changes.
I'm hoping someone will be able to help me out
Hi I am trying to create a custom loading bar view by subclassing UIView. I want to create one UIView with a fixed frame, and another UIView that is inside of it. When I initialize the inner UIView, with the frame passed in by this method override init(frame: CGRect), the two views have different origins. I want the two views to be directly on top of each other to start out. I also want to be able to update the innerBar by calling this uploadBar.setLoadingPercentage(percent: 53.5)
Here is the code:
Creating the UploadBar
let uploadBar = UploadBar(frame: CGRect(x: 40, y: 40, width: 400, height: 40))
view.addSubview(uploadBar)
Subclassing UploadBar
import UIKit
class UploadBar: UIView {
var innerBar: UIView!
override init(frame: CGRect) {
super.init(frame: frame)
backgroundColor = UIColor.white
innerBar = UIView(frame: frame)
innerBar.backgroundColor = UI.customBlue()
addSubview(innerBar)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func setLoadingPercentage(percent: Double) {
// change innerBar's frame and redraw
}
}
For your inner view, you only require the width and height from the parent rect. The x and y should be zero relative to the parent view:
override init(frame: CGRect) {
super.init(frame: frame)
backgroundColor = UIColor.white
let innerRect = CGRect(x: 0, y: 0, width: frame.width, height: frame.height)
innerBar = UIView(frame: innerRect)
innerBar.backgroundColor = UI.customBlue()
addSubview(innerBar)
}