aheze

let item = provider.items[indexPath.row] as! MyViewModel   
let textHeight = item.title.count
let extensionHeight = Double(textHeight) * 0.70
return AdaptiveCollectionConfig.cellBaseHeight + CGFloat(textHeight) + CGFloat(extensionHeight)

aheze

let item = provider.items[indexPath.row] as! MyViewModel 
let textHeight = item.title.heightWithConstrainedWidth(width: width-24, font: UIFont.systemFont(ofSize: 10))
//Minus 24 points because that is the padding of the edges of the label
let extensionHeight = Double(textHeight) * 0.70
return AdaptiveCollectionConfig.cellBaseHeight + CGFloat(textHeight) + CGFloat(extensionHeight)

aheze

extension String {
    func heightWithConstrainedWidth(width: CGFloat, font: UIFont) -> CGFloat {
        let constraintRect = CGSize(width: width, height: .greatestFiniteMagnitude)
        let boundingBox = self.boundingRect(with: constraintRect, options: [.usesLineFragmentOrigin, .usesFontLeading], attributes: [NSAttributedString.Key.font: font], context: nil)
        return boundingBox.height
    }
}

aheze

//: A UIKit based Playground for presenting user interface
  
import UIKit
import PlaygroundSupport

class MyViewController : UIViewController, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout, UICollectionViewDataSource {
    
  ///1.
    var baseCollectionViewArray = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]
    var secondCollectionViewArray = [String]()

aheze

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
      if collectionView == baseCollectionView {
          let alphabetLetter = baseCollectionViewArray[indexPath.item]
          secondCollectionViewArray.append(alphabetLetter)
          let newIndexPath = IndexPath(item: secondCollectionViewArray.count - 1, section: 0)
          secondCollectionView.insertItems(at: [newIndexPath])
          ///First, add a cell to the second collectionview.

          baseCollectionViewArray.remove(at: indexPath.item)
          baseCollectionView.deleteItems(at: [indexPath])

aheze

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    if collectionView == baseCollectionView {
        let alphabetLetter = baseCollectionViewArray[indexPath.item]
        secondCollectionViewArray.append(alphabetLetter)
        let newIndexPath = IndexPath(item: secondCollectionViewArray.count - 1, section: 0)
        secondCollectionView.insertItems(at: [newIndexPath])

        baseCollectionViewArray.remove(at: indexPath.item)
        baseCollectionView.deleteItems(at: [indexPath])

aheze

class AlphabetComponent: NSObject {
    var labelName = ""
    var orderIdentifier = 0
}

aheze

class MyViewController : UIViewController, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout, UICollectionViewDataSource {

///.......
override func loadView() {
  let view = UIView()
  view.backgroundColor = .white
  
 ///ADD this stuff:
  for (index, singleLetter) in baseCollectionViewArray.enumerated() {
      let newComponent = AlphabetComponent()

aheze

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! AlphabetCollectionCell

    if collectionView == baseCollectionView {
        ///We have 2 collectionviews, so we must differentiate.
        cell.backgroundColor = .green
        cell.nameLabel.text = newBaseCollectionViewArray[indexPath.item].labelName
    } else {
        cell.backgroundColor = .red
        cell.nameLabel.text = secondCollectionViewArray[indexPath.item].labelName

aheze

func calculateWhereToPlaceComponent(component: AlphabetComponent, placeInSecondCollectionView: IndexPath) {
    let componentOrderID = component.orderIdentifier

    var indexPathToAppendTo = 0
    for (index, singleComponent) in newBaseCollectionViewArray.enumerated() {
        ///We are going to check if the singleComponent's order identifier is smaller than componentOrderID.
        ///If it is smaller, we know we must insert the cell ONE to the right of this indexPath.
        if singleComponent.orderIdentifier < componentOrderID {
            indexPathToAppendTo = index + 1
        }