Swift - Draw lines between several random CGPoints - swift

I am trying to create a simple line graph that should display the average monthly user score. So far I have created a collectionView with a white dot at the top of each cell, but now I would like to have a straight line between each dot. I have added a temporary array for testing purposes.
Since it will be variable server data (the last six months), the location of the dots can be different each time. What should I do to connect the first dot with the second one and the second one with the next one (until all dots are connected)?
User profile data controller
class UserProfileData: UICollectionViewController, UICollectionViewDelegateFlowLayout {
var cellId = "cellId"
let values: [CGFloat] = [4.5, 3.2, 4.8, 5.0, 2.3, 2.9]
init() {
let layout = UICollectionViewFlowLayout()
layout.scrollDirection = UICollectionViewScrollDirection.horizontal
super.init(collectionViewLayout: layout)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func viewDidLoad() {
super.viewDidLoad()
self.collectionView?.dataSource = self
self.collectionView?.delegate = self
collectionView?.backgroundColor = Constants.MAIN_THEME_COLOR
collectionView?.isScrollEnabled = false
collectionView?.register(BarCell.self, forCellWithReuseIdentifier: cellId)
}
// MARK: UICollectionViewDataSource
override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return values.count
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: 50, height: view.frame.height - 20)
}
override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! BarCell
if let max = values.max() {
let value = values[indexPath.item]
let ratio = value / max
cell.barHeightConstraint?.constant = view.frame.height * ratio
}
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
return UIEdgeInsets(top: 0, left: 4, bottom: 0, right: 4)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
return 10
}
}
My custom cell
// Create custom cell(s)
class BarCell: UICollectionViewCell {
let barView: UIView = {
let view = UIView()
view.backgroundColor = .clear
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
let barLabel: UILabel = {
let label = UILabel()
label.text = "."
label.textColor = .white
label.font = UIFont.systemFont(ofSize: 70)
label.translatesAutoresizingMaskIntoConstraints = false
return label
}()
var barHeightConstraint: NSLayoutConstraint?
override init(frame: CGRect) {
super.init(frame: frame)
addSubview(barView)
barView.addSubview(barLabel)
barHeightConstraint = barView.heightAnchor.constraint(equalToConstant: 300)
barHeightConstraint?.isActive = true
barHeightConstraint?.constant = 100
barView.leftAnchor.constraint(equalTo: leftAnchor).isActive = true
barView.rightAnchor.constraint(equalTo: rightAnchor).isActive = true
barView.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
barLabel.centerXAnchor.constraint(equalTo: barView.centerXAnchor).isActive = true
barLabel.topAnchor.constraint(equalTo: barView.topAnchor, constant: 5).isActive = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}

A UICollectionView has a backgroundView property. You should be able to set the backgroundView of your UICollectionView to a custom UIView that draws the lines between your items.

Related

Make UICollectionViewCells with UIImageView height based on image

I want to make a UICollectionView with the cells the width of the screen, but the height is based on the aspect ratio of the UIImageView inside.
In my current implementation all of the UICollectionViewCell instances are squares and this isn't what I want.
I want to use auto layout somehow to make the size of the image the width of the screen, but the relevant height depends on the aspect ratio of the image used.
Everything is done programatically in code.
My code:
class ViewController: UIViewController {
var data = ["1","2","3","4","5","6","7","8","1","2","3","4","5","6","7","8"]
var collectionView: UICollectionView!
override func viewDidLoad() {
super.viewDidLoad()
self.collectionView.dataSource = self
self.collectionView.delegate = self
self.collectionView.register(SubclassedCollectionViewCell.self, forCellWithReuseIdentifier: "cell")
self.collectionView.alwaysBounceVertical = true
self.collectionView.backgroundColor = .white
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
}
override func loadView() {
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
layout.itemSize = CGSize(width: UIScreen.main.bounds.size.width - 20, height: UIScreen.main.bounds.size.width / 1)
layout.scrollDirection = .vertical
collectionView = UICollectionView(frame: .zero, collectionViewLayout: layout)
self.view = collectionView
}
}
extension ViewController: UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
data.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as? SubclassedCollectionViewCell {
let data = self.data[indexPath.item]
cell.setupCell(image: data)
return cell
}
fatalError("Could not dequeue cell")
}
}
with the cell
class SubclassedCollectionViewCell: UICollectionViewCell {
var hotelImageView: UIImageView = {
var hotelView = UIImageView()
hotelView.contentMode = .scaleAspectFill
hotelView.clipsToBounds = true
return hotelView
}()
override init(frame: CGRect) {
super.init(frame: frame)
addSubview(hotelImageView)
hotelImageView.translatesAutoresizingMaskIntoConstraints = false
hotelImageView.topAnchor.constraint(equalTo: topAnchor).isActive = true
hotelImageView.leftAnchor.constraint(equalTo: leftAnchor).isActive = true
hotelImageView.rightAnchor.constraint(equalTo: rightAnchor).isActive = true
hotelImageView.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func setupCell(image: String) {
if let image : UIImage = UIImage(named: image) {
hotelImageView.image = image
}
}
}
First, calculate the ratio based on the width and multiply by collection view width you can get a new height based on width.
Final Code: Remove itemSize from the loadview function. And calculate height and return item size in sizeForItemAt method.
loadView
override func loadView() {
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
// layout.itemSize = CGSize(width: UIScreen.main.bounds.size.width - 20, height: UIScreen.main.bounds.size.width / 1) <-- Remove this
layout.scrollDirection = .vertical
collectionView = UICollectionView(frame: .zero, collectionViewLayout: layout)
self.view = collectionView
}
UICollectionViewDelegateFlowLayout
extension ViewController: UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
data.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as? SubclassedCollectionViewCell {
let data = self.data[indexPath.item]
cell.setupCell(image: data)
return cell
}
fatalError("Could not dequeue cell")
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
guard let iamgeData = UIImage(named: self.data[indexPath.item]) else {
return .zero
}
let width = collectionView.bounds.width
let heightOnWidthRatio = iamgeData.size.height / iamgeData.size.width
let height = width * heightOnWidthRatio
return CGSize(width: width, height: height)
}
}

Adjusting UICollectionView Header height?

I am trying to adjust the height of my CollectionView Header based on the height of myView's height. for example I want to be able to type:
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
return CGSize(width: view.frame.width, height: 100)
} //Instead of 100 I want to say: **myView.frame.height**
but since I have created myView inside the header class I can't access it, I was wondering if anyone could help me with this or has any better way of doing this. I would really appreciate it!
This is my code:
class MyProfileCollectionView: UICollectionViewController, UICollectionViewDelegateFlowLayout {
override func viewDidLoad() {
super.viewDidLoad()
self.collectionView?.register(MyProfileHeader.self, forSupplementaryViewOfKind: UICollectionElementKindSectionHeader, withReuseIdentifier: headerIdentifier)
}
override func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind:
String, at indexPath: IndexPath) -> UICollectionReusableView {
let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier:
headerIdentifier, for: indexPath) as! MyProfileHeader
header.backgroundColor = .red
return header
} //HERE
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
return CGSize(width: view.frame.width, height: 111)
}
}
And this is my Header class where I have created myView:
class MyProfileHeader: UICollectionReusableView, UICollectionViewDelegate {
override init(frame: CGRect) {
super.init(frame: frame)
self.addSubview(myView)
myView.widthAnchor.constraint(equalToConstant: 50).isActive = true
myView.heightAnchor.constraint(equalToConstant: 70).isActive = true
myView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
myView.rightAnchor.constraint(equalTo: self.rightAnchor).isActive = true
}
//I want my headers height be equal to myView's height so if i change myView's height the headers height changes automatically.
var myView: UIView = {
let view = UIView()
view.translatesAutoresizingMaskIntoConstraints = false
view.backgroundColor = .gray
return view
}()
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
Somehow you are using the magic number for the height of your myview inside MyProfileHeader class like myView.heightAnchor is 70. For a quick solution, you can use a static variable inside MyProfileHeader or outside.
class MyProfileHeader: UICollectionReusableView, UICollectionViewDelegate {
static var height: CGFloat = 70.0
override init(frame: CGRect) {
super.init(frame: frame)
self.addSubview(myView)
myView.widthAnchor.constraint(equalToConstant: 50).isActive = true
myView.heightAnchor.constraint(equalToConstant: MyProfileHeader.height).isActive = true
myView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
myView.rightAnchor.constraint(equalTo: self.rightAnchor).isActive = true
}
- - - - - -
}
Now you can use that in layout return:
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
return CGSize(width: view.frame.width, height: MyProfileHeader.height)
}

uicollectionviewcells not showing [duplicate]

I have got this Swift code
`
let cellId="cellId"
class FeedController: UICollectionViewController{
override func viewDidLoad() {
super.viewDidLoad()
navigationItem.title = "Centill"
collectionView?.reloadData()
collectionView?.backgroundColor = UIColor(white: 0.95, alpha: 1)
collectionView?.register(FeedCell.self, forCellWithReuseIdentifier: cellId)
}
override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 3
}
override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell=collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath);
cell.backgroundColor = .yellow
return cell
}
}
class FeedCell: UICollectionViewCell {
override init(frame: CGRect){
super.init(frame: frame)
setupViews()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func setupViews(){
backgroundColor = .yellow
}
}
`
But unfortunately my cells are not showing.It only shows navigation bar and background color.what may be the problem with my code?
Try This code:
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
layout.sectionInset = UIEdgeInsets(top: 20, left: 10, bottom: 10, right: 10)
layout.itemSize = CGSize(width: 60, height: 60)
let myCollectionView:UICollectionView = UICollectionView(frame: self.view.frame, collectionViewLayout: layout)
myCollectionView.dataSource = self
myCollectionView.delegate = self
myCollectionView.registerClass(UICollectionViewCell.self, forCellWithReuseIdentifier: "MyCell")
myCollectionView.backgroundColor = UIColor.whiteColor()
self.view.addSubview(myCollectionView)
You have to provide the size for collection view cell. add the below code snippet
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
// calculate and return the height
}
In your cellForItemAt dataSource method you need to give custom UICollectionCell Class
let cell=collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! FeedCell
cell.backgroundColor = .yellow
return cell
Then you will able to see cell.
Try it.
You add in the class
UICollectionViewDataSource and UICollectionVIewDelegate.

Swift collectionViewCells are not showing

I have got this Swift code
`
let cellId="cellId"
class FeedController: UICollectionViewController{
override func viewDidLoad() {
super.viewDidLoad()
navigationItem.title = "Centill"
collectionView?.reloadData()
collectionView?.backgroundColor = UIColor(white: 0.95, alpha: 1)
collectionView?.register(FeedCell.self, forCellWithReuseIdentifier: cellId)
}
override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 3
}
override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell=collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath);
cell.backgroundColor = .yellow
return cell
}
}
class FeedCell: UICollectionViewCell {
override init(frame: CGRect){
super.init(frame: frame)
setupViews()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func setupViews(){
backgroundColor = .yellow
}
}
`
But unfortunately my cells are not showing.It only shows navigation bar and background color.what may be the problem with my code?
Try This code:
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
layout.sectionInset = UIEdgeInsets(top: 20, left: 10, bottom: 10, right: 10)
layout.itemSize = CGSize(width: 60, height: 60)
let myCollectionView:UICollectionView = UICollectionView(frame: self.view.frame, collectionViewLayout: layout)
myCollectionView.dataSource = self
myCollectionView.delegate = self
myCollectionView.registerClass(UICollectionViewCell.self, forCellWithReuseIdentifier: "MyCell")
myCollectionView.backgroundColor = UIColor.whiteColor()
self.view.addSubview(myCollectionView)
You have to provide the size for collection view cell. add the below code snippet
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
// calculate and return the height
}
In your cellForItemAt dataSource method you need to give custom UICollectionCell Class
let cell=collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! FeedCell
cell.backgroundColor = .yellow
return cell
Then you will able to see cell.
Try it.
You add in the class
UICollectionViewDataSource and UICollectionVIewDelegate.

didSelectItemAt: not being called (UICollectionView)

I have a UICollectionView in a UIView class because it's implemented in an other class.I set the delegate and dataSource and allowsSelection to true but didSelectItemAt method doesn't work and I can't figure out why.This is the code:
class NewRecipeViewCategoryCV: UIView, UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {
lazy var collectionView: UICollectionView = {
let layout = UICollectionViewFlowLayout()
layout.scrollDirection = .horizontal
let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
cv.showsHorizontalScrollIndicator = false
cv.backgroundColor = UIColor.white
cv.translatesAutoresizingMaskIntoConstraints = false
cv.dataSource = self
cv.delegate = self
cv.allowsSelection = true
return cv
}()
let newRecipeModel = NewRecipeModel()
let cellId = "cellId"
override init(frame: CGRect) {
super.init(frame: frame)
collectionView.register(NewRecipeViewCategory.self, forCellWithReuseIdentifier: cellId)
addSubview(collectionView)
collectionView.topAnchor.constraint(equalTo: topAnchor).isActive = true
collectionView.leftAnchor.constraint(equalTo: leftAnchor).isActive = true
collectionView.heightAnchor.constraint(equalTo: heightAnchor).isActive = true
collectionView.widthAnchor.constraint(equalTo: widthAnchor).isActive = true
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return newRecipeModel.recipeCategory.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! NewRecipeViewCategory
cell.categoryText.text = newRecipeModel.recipeCategory[indexPath.item].uppercased()
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print(123)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let category: UILabel = {
let category = UILabel()
category.text = "BREAKFAST"
category.font = UIFont(name: "SourceSansPro-Regular", size: 13)
category.translatesAutoresizingMaskIntoConstraints = false
category.textColor = UIColor.black
category.sizeToFit()
return category
}()
return CGSize(width: category.frame.width+15, height: category.frame.height+12)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}