I have tableView and on top of it an imageView. Made stretchable header with this guide https://github.com/abhimuralidharan/StretchableTableViewHeader-Swift
And now I have to add label on my image. This label should change size/font when tableView is scrolling.
I created my imageView in another class:
class LotteryHeaderView: UIImageView {
let ticketsCountLabel: UILabel = {
let label = UILabel()
label.textColor = .white
label.translatesAutoresizingMaskIntoConstraints = false
label.font = UIFont.boldSystemFont(ofSize: 100)
return label
}()
let infoLabel: UILabel = {
let label = UILabel()
label.textColor = .white
label.textAlignment = .center
label.translatesAutoresizingMaskIntoConstraints = false
label.font = UIFont.systemFont(ofSize: 13, weight: .medium)
label.numberOfLines = 2
label.text = Localizable.all_user_tickets_count()
return label
}()
override init(frame: CGRect) {
super.init(frame: frame)
self.addSubViews([ticketsCountLabel, infoLabel])
ticketsCountLabel.centerX(to: self.centerXAnchor)
.centerY(to: self.centerYAnchor)
infoLabel.top(to: ticketsCountLabel.bottomAnchor, constant: 7)
.width(constant: 184)
.centerX(to: self.centerXAnchor)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
Initialized it in my controller:
let imageView = LotteryHeaderView(frame: CGRect(x: 0, y: 0, width: Constants.Size.screenWidth, height: 300))
Setup in viewDidLoad:
imageView.frame = CGRect(x: 0, y: 0, width: Constants.Size.screenWidth, height: 300)
imageView.image = R.image.santa_fe()
imageView.contentMode = .scaleAspectFill
imageView.clipsToBounds = true
view.addSubview(imageView)
Here func which gets called every time the tableview is scrolled, and it works for my image (it collapsable and stretchable):
func scrollImageInHeader(scrollView: UIScrollView) {
let y = 300 - (scrollView.contentOffset.y + 300)
let height = min(max(y, 60), 450)
imageView.frame = CGRect(x: 0, y: 0, width: Constants.Size.screenWidth, height: height)
}
Tried to add in scrollImageInHeader() code under, from this StackOverFlowAnswer, but it doesn't help
let offset = scrollView.contentOffset.y
let scale = min(max(1.0 - offset / 200.0, 0.0), 1.0)
imageView.ticketsCountLabel.transform = CGAffineTransform(scaleX: scale, y: scale)
Please, any help will be appreciated.
UIScrollView is parent UITableViewController. You use UIScrollView with UIScrollViewDelegate for setup label font size with scrollOffset: CGFloat follow .y
extension ViewController: UIScrollViewDelegate{
func scrollViewDidScroll(_ scrollView: UIScrollView) {
var scrollOffset : CGFloat = scrollView.contentOffset.y
// process with scrollOffset
}
}
Actually I found my mistake. Code from Here helped.
Class LotteryHeaderView I changed to UIView and added there an UIImageView.
Related
Am not working with storyboards, and below is the full code for my UIViewController for my Main Menu screen. While everything appears to work, I made an error, but don't understand the outcome.
myView, the gray area is set to the safeareaLayout constraints
fillRects is a function where I prefill all the rects for the labels and buttons that I will place on myView
By accident, I passed the wrong view to fillRects, not myView, as intended. Therefore the UILabel I create below is larger than it should be.
But my understanding was that it should have been cropped since it is a child of myView, which is constrained to the safeAreaLayout guide. Yet from the included image, you can see that it goes beyond myView's area on the screen.
Is my error in the way I applied the safeareaLayout guides? Or my understanding as to how they work?
import UIKit
class MainMenuCtrl: UIViewController {
var viewBounds : CGRect = .zero
var topLabelRect : CGRect = .zero
var bottomLabelRect : CGRect = .zero
var menuRect : CGRect = .zero
private let myView : UIView = {
let myView = UIView()
myView.translatesAutoresizingMaskIntoConstraints = false
myView.backgroundColor = .gray
return myView
}()
override func viewDidLoad() {
super.viewDidLoad()
// Set background color func
setBGC(vc: view)
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
view.backgroundColor = .green
view.addSubview(myView)
addContraints(main: view, child: myView)
////fill the CGRects for all the labels, and buttons
fillRects(vc: self)
let label = UILabel(frame: self.topLabelRect)
label.textAlignment = .center
label.backgroundColor = .red
label.text = "hello"
label.textColor = nameColor
label.font = .systemFont(ofSize: 40)
label.adjustsFontSizeToFitWidth = true
label.minimumScaleFactor = 0.7
myView.addSubview(label)
}
override var prefersStatusBarHidden: Bool {
return false
}
override var preferredStatusBarStyle: UIStatusBarStyle {
return .darkContent
}
}
Here is the code for fillRects
func fillRects (vc: MainMenuCtrl) {
vc.viewBounds = vc.view.frame
vc.topLabelRect = CGRect(x: vc.viewBounds.minX, y: vc.viewBounds.minY,
width: vc.viewBounds.width, height: vc.viewBounds.height * 0.05)
vc.bottomLabelRect = CGRect(x: vc.viewBounds.minX, y: vc.viewBounds.height * 0.9,
width: vc.viewBounds.width, height: vc.viewBounds.height * 0.05)
vc.menuRect = CGRect(x: vc.viewBounds.minX, y: vc.viewBounds.height * 0.2,
width: vc.viewBounds.width, height: vc.viewBounds.height * 0.6)
}
A view has a clipToBounds property that dictates whether subViews are restricted to the bounds of their parent view. The default value for this is false, which explains the behaviour you are experiencing.
Setting view.clipToBounds = true on the parent view should result in the sub view behaving as you expected.
I am trying to make a view programatically, making a card with an image and some text and overlaying it with some color. I have turned off clip to bounds and added some colors to make it more visual.
So when I set
overlay.frame = self.frame
or
overlay.frame = CGRect(x: 0, y: 0, width: frame.width, height: frame.height)
the overlay should cover the entire view but it does not, why is this?
This is what is showing
This is what I want to see, but with each card having a blue layer on top
private var leftImage: UIImageView = {
let i = UIImageView(frame: .zero)
i.contentMode = .scaleAspectFill
i.image = UIImage()
return i
}()
private var topLabel: UILabel = {
let label = UILabel(frame: .zero)
label.isUserInteractionEnabled = false
label.font = UIFont.boldSystemFont(ofSize: 16.0)
label.lineBreakMode = .byWordWrapping
label.adjustsFontSizeToFitWidth = true
label.numberOfLines = 2
return label
}()
var bottomLabel: UILabel = {
let label = UILabel(frame: .zero)
label.isUserInteractionEnabled = false
label.lineBreakMode = .byWordWrapping
label.font = UIFont.systemFont(ofSize: 12.0)
label.numberOfLines = 1
label.text = "60 seconds"
return label
}()
private var stackView: UIStackView = {
let stack = UIStackView(frame: .zero)
stack.axis = .vertical
stack.isUserInteractionEnabled = false
stack.distribution = .fillEqually
stack.layoutMargins = UIEdgeInsets(top: 5, left: 5, bottom: 5, right: 5)
stack.isLayoutMarginsRelativeArrangement = true
return stack
}()
private var overlay: UIView = {
let view = UIView(frame: .zero)
view.backgroundColor = .blue
view.alpha = 0.8
//view.isHidden = true
return view
}()
override init(frame: CGRect) {
super.init(frame: frame)
create()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
create()
}
private func create() {
self.translatesAutoresizingMaskIntoConstraints = false
//leftview
leftImage.frame = CGRect(x: 0, y: 0, width: frame.width / 2, height: frame.height)
addSubview(leftImage)
//rightVIew
stackView.frame = CGRect(x: frame.midX, y: 0, width: frame.width / 2, height: frame.height)
clipsToBounds = false
//add views to stack
stackView.addArrangedSubview(topLabel)
stackView.addArrangedSubview(bottomLabel)
addSubview(stackView)
overlay.frame = CGRect(x: 0, y: 0, width: frame.width, height: frame.height)
addSubview(overlay)
//card styling
layer.cornerRadius = 10
}
overlay.frame = self.frame
That can never be right, except by accident, because the frame of overlay and the frame of self are in two different coordinate systems. At the very least you want to say
overlay.frame = self.bounds // bounds, not frame
However, that isn't going to work either unless you say it in the right place. The right place is when layout occurs:
override func layoutSubviews() {
super.layoutSubviews()
self.overlay.frame = self.bounds
}
Simply adding that to your existing code should solve the problem.
The issue is that you're setting your overlay's dimensions like so:
overlay.frame = CGRect(x: 0, y: 0, width: frame.width, height: frame.height)
before the superview has determined its final width and height. You'll need to do one of the following:
Call create() after the superview class has determined its final size
Continuously set the overlay's frame as the superview's width and height changes (see https://developer.apple.com/documentation/uikit/uiview/1622482-layoutsubviews)
Use AutoLayout constraints via a xib/storyboard file
I made a program from one youtube channel and ran into a problem. I think that it is related to the layout. On different devices displayed differently. And can someone tell me how to fix what text will fit onto another one and how to make the image appear on the whole my CustomView.
import UIKit struct scrollViewDataStruct {
let title: String?
let image: UIImage?
} class ScrollController: UIViewController, UIScrollViewDelegate{
#IBOutlet weak var scrollView: UIScrollView!
var scrollViewData = [scrollViewDataStruct]()
var viewTagValue = 10
var tagValue = 100
override func viewDidLoad() {
super.viewDidLoad()
scrollView.delegate = self
scrollViewData = [scrollViewDataStruct.init(title: "There was written a very large line that climbs to another line", image: #imageLiteral(resourceName: "knowledge_graph_logo")),
scrollViewDataStruct.init(title: "Second", image: #imageLiteral(resourceName: "knowledge_graph_logo"))]
scrollView.contentSize.width = self.scrollView.frame.width * CGFloat(scrollViewData.count)
var i = 0
for data in scrollViewData {
let view = CustomView(frame: CGRect(x: 10 + (self.scrollView.frame.width * CGFloat(i)), y: 200, width: self.scrollView.frame.width - 75, height: self.scrollView.frame.height - 90))
view.imageView.image = data.image
view.tag = i + viewTagValue
self.scrollView.addSubview(view)
let label = UILabel(frame: CGRect.init(origin: CGPoint.init(x: 0, y: 20), size: CGSize.init(width: 0, height: 40)))
label.text = data.title
label.font = UIFont.boldSystemFont(ofSize: 30)
label.textColor = UIColor.black
label.sizeToFit()
label.tag = i + tagValue
if i == 0 {
label.center.x = view.center.x
} else {
label.center.x = view.center.x - self.scrollView.frame.width / 2
}
self.scrollView.addSubview(label)
i += 1
}
}
func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView == scrollView {
for i in 0..<scrollViewData.count {
let label = scrollView.viewWithTag(i + tagValue) as! UILabel
let view = scrollView.viewWithTag(i + viewTagValue) as! CustomView
var scrollContentOffset = scrollView.contentOffset.x + self.scrollView.frame.width
var viewOffset = (view.center.x - scrollView.bounds.width / 4) - scrollContentOffset
label.center.x = scrollContentOffset - ((scrollView.bounds.width / 4 - viewOffset) / 2)
}
}
}}class CustomView: UIView {
let imageView: UIImageView = {
let imageView = UIImageView()
imageView.translatesAutoresizingMaskIntoConstraints = false
imageView.backgroundColor = UIColor.darkGray
imageView.contentMode = .scaleAspectFit
return imageView
}()
override init(frame: CGRect) {
super.init(frame: frame)
self.addSubview(imageView)
imageView.leftAnchor.constraint(equalTo: self.leftAnchor).isActive = true
imageView.rightAnchor.constraint(equalTo: self.rightAnchor).isActive = true
imageView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
imageView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}}
This is a launch on iPhone 5s
This is a launch on iPhone 8 plus
What you should be doing is setting the width of each UILabel to the size of the CustomView that contains the image, and setting each label's "numberOfLines" to 0 and set the lineBreak to wordWrap. This should, in theory, let the labels only be the width of the images AND let the UILabels fit the size of the text vertically, rather than horizontally - which is what sizeToFit does.
I'm trying to show simple custom view into scrollView. Here's my code :
struct scrollViewDataStruct {
let title: String?
let image: UIImage?
}
class ViewController: UIViewController {
#IBOutlet weak var scrollView: UIScrollView!
var scrollViewData = [scrollViewDataStruct]()
override func viewDidLoad() {
super.viewDidLoad()
scrollViewData = [
scrollViewDataStruct(title: "First", image: #imageLiteral(resourceName: "iPhone 8 Copy 2")),
scrollViewDataStruct(title: "Second", image: #imageLiteral(resourceName: "iPhone 8 Copy 3"))
]
self.scrollView.backgroundColor = .yellow
scrollView.contentSize.width = self.scrollView.frame.width * CGFloat(scrollViewData.count)
var i = 0
for _ in scrollViewData {
let view = CustomView(frame: CGRect(x: self.scrollView.frame.width * CGFloat(i), y: 0, width: scrollView.frame.width, height: self.scrollView.frame.height))
self.scrollView.addSubview(view)
i += 1
}
// Do any additional setup after loading the view, typically from a nib.
}
}
class CustomView: UIView {
let imageView: UIImageView = {
let imageView = UIImageView()
imageView.translatesAutoresizingMaskIntoConstraints = false
imageView.backgroundColor = UIColor.blue
return imageView
}()
override init(frame: CGRect) {
super.init(frame: frame)
self.addSubview(imageView)
imageView.leftAnchor.constraint(equalTo: self.leftAnchor).isActive = true
imageView.rightAnchor.constraint(equalTo: self.rightAnchor).isActive = true
imageView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
imageView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
As you can see, the CustomView's frame = scrollView's frame but when i ran application it's not as I expected :
Then, in storyboard, i change device from iphone8 to iphone 8 plus and run again. It's show CustomView correctly. I have no idea, the scrollView is always correct but the CustomView is not .
Any suggest ?
Your problem is that you are accessing the frame of the scrollView before Auto Layout has run and established the size of the frame for the actual device. A quick fix is to move your setup code into an override of viewDidLayoutSubviews.
You have to be careful though, because unlike viewDidLoad, viewDidLayoutSubviews will run more than once, so you have to make sure you don't add your views multiple times.
// property - have we set up the views yet?
var setup = false
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
if !setup {
scrollView.contentSize.width = self.scrollView.frame.width * CGFloat(scrollViewData.count)
var i = 0
for _ in scrollViewData {
let view = CustomView(frame: CGRect(x: self.scrollView.frame.width * CGFloat(i), y: 0, width: scrollView.frame.width, height: self.scrollView.frame.height))
self.scrollView.addSubview(view)
i += 1
}
setup = true
}
}
You should consider using constraints to place your views within your scrollView content instead of messing with the frame calculations, then Auto Layout would just automatically do the right thing.
In viewDidLoad, UI component will suppose to have the size you have taken in storyboard.
There are 2 ways to do this:
1. Use autoresizingMask property
autoresizingMask property will resize the view, if its containerView's frames changed
var i = 0
for _ in scrollViewData {
let view = CustomView(frame: CGRect(x: self.scrollView.frame.width * CGFloat(i), y: 0, width: scrollView.frame.width, height: self.scrollView.frame.height))
view.autoresizingMask = .flexibleHeight
self.scrollView.addSubview(view)
i += 1
}
2. Use fixed parameters, say UIScreen.main.bounds.size.height
Just update your code for custom view's height with reference to screen height rather than scroll view's height. It will work fine
var i = 0
let height = UIScreen.main.bounds.size.height
for _ in scrollViewData {
let view = CustomView(frame: CGRect(x: self.scrollView.frame.width * CGFloat(i), y: 0, width: scrollView.frame.width, height: height))
self.scrollView.addSubview(view)
i += 1
}
I have the following code running on Xcode Playground. However, even though I specify that the label is centered at the center of the view, it doesn't appear there.
import UIKit
import PlaygroundSupport
class TestViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = UIColor.white
let label = UILabel(frame: CGRect(x: 0, y: 0, width: 100, height: 20))
label.center = CGPoint(x: view.frame.width / 2, y: view.frame.height / 2)
label.text = "Hello World!"
label.textColor = UIColor.black
view.addSubview(label)
}
}
PlaygroundPage.current.liveView = TestViewController()
The view controller's view's frame is not final in viewDidLoad.
You either need to set the label's autoresizingMask or apply constraints to keep it in the center.
And since you made the label wider than the text, you also need to set the label's textAlignment to center.
let label = UILabel(frame: CGRect(x: 0, y: 0, width: 100, height: 20))
label.center = view.center
label.text = "Hello World!"
label.textColor = .black
label.textAlignment = .center // or call label.sizeToFit()
label.autoresizingMask = [ .flexibleTopMargin, .flexibleBottomMargin, .flexibleLeftMargin, .flexibleRightMargin, ]
view.addSubview(label)
view frame is not finalized when viewDidLoad is triggered, you need to set the frame of the label inside the method viewDidLayoutSubviews as this method is being invoked when view bound was finalized.
Try
class TestViewController: UIViewController {
let label = UILabel(frame: CGRect(x: 0, y: 0, width: 100, height: 20))
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = UIColor.white
label.text = "Hello World!"
label.textColor = UIColor.black
self.view.addSubview(label)
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
self.label.center = self.view.center
}
}