Dynamic CollectionViewCell In TableViewCell Swift

问题:

Question:

How To Make UITableViewCell Height Dynamic according the UICollectionViewCell?

View Hierarchy:

UIViewController

UITableView

UITableViewCell

UICollectionView

UICollectionViewCell1

Label 1

UICollectionViewCell2

Label 2

UICollectionViewCell3

Label 3

[So on]

Explanation:

Here Label1, Label2, label 3 are have dynamic height and numberOfRows in UICollectionView is also dynamic. I need Height of UITableViewCell according to the UICollectionViewCell.

回答1:

View Hierarchy In UIViewController

Steps:

1. Bind Delegate And Datasource

   • Bind UItableView Delegate and datasource with the UIViewController.

   • Bind UICollectionView Delegate and datasource with the UItableViewCell here TblCell.

2. In UIViewController

   class CollectionVC: UIViewController, UITableViewDataSource, UITableViewDelegate {
   
   :
   :
   
   func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
       return UITableViewAutomaticDimension // For tableCell Dynamic Height
   }
   
   func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
       return 200 // For tableCell Estimated Height
   }
   // Above two delegates must be necessary or you can use property for same.
   
   
   func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
       return 1 // returning 1, as per current single cell
   }
   
   func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
       let cell = tableView.dequeueReusableCell(withIdentifier: "TblCell") as! TblCell
   
       return cell
   }
   }
   

3. In TblCell

   class TblCell: UITableViewCell , UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout{
   
   @IBOutlet var colViewObj: UICollectionView!
   
   // Array for Label
   var arrData = ["Hello", "How re you?", "rock the world", "Nice to meet you.", "Hey! It is awsome."]
   
   
   override func awakeFromNib() {
       super.awakeFromNib()
       // Initialization code
   
       self.colViewObj.isScrollEnabled = false
   }
   
   override func setSelected(_ selected: Bool, animated: Bool) {
       super.setSelected(selected, animated: animated)
   
       // Configure the view for the selected state
   }
   
   func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
   
        // Get width of Label As per String characters.
       let aWidth : CGFloat = arrData[indexPath.row].width(withConstraintedHeight: 40, font: UIFont.systemFont(ofSize: 17.0))
   
       return CGSize(width: aWidth + 40 , height: 40)
   }
   
   // THIS IS THE MOST IMPORTANT METHOD
   //
   // This method tells the auto layout
   // You cannot calculate the collectionView content size in any other place, 
   // because you run into race condition issues.
   
   override func systemLayoutSizeFitting(_ targetSize: CGSize, withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority, verticalFittingPriority: UILayoutPriority) -> CGSize {
   
       // If the cell's size has to be exactly the content 
       // Size of the collection View, just return the
       // collectionViewLayout's collectionViewContentSize.
   
       self.colViewObj.frame = CGRect(x: 0, y: 0,
                                      width: targetSize.width, height: 600)
       self.colViewObj.layoutIfNeeded() 
   
       // It Tells what size is required for the CollectionView
       return self.colViewObj.collectionViewLayout.collectionViewContentSize
   
   }
   
   func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
       return arrData.count
   }
   
   func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
       let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ColViewCell", for: indexPath) as! ColViewCell
   
       cell.lblTitle.text = arrData[indexPath.item]
   
       cell.lblTitle.layer.borderColor = UIColor.black.cgColor
       cell.lblTitle.layer.borderWidth = 1.0
   
       return cell
   }
   
   }
   
   extension String {
   
   func width(withConstraintedHeight height: CGFloat, font: UIFont) -> CGFloat {
       let constraintRect = CGSize(width: .greatestFiniteMagnitude, height: height)
       let boundingBox = self.boundingRect(with: constraintRect, options: .usesLineFragmentOrigin, attributes: [NSFontAttributeName: font], context: nil)
   
       return ceil(boundingBox.width)
   }
   }
   

Output:

• Red Border : UITableViewCell
• Yellow Border : UICollectionViewCell

• Black Outline : Label

  with UICollectionViewDelegateFlowLayout

without UICollectionViewDelegateFlowLayout

Reference:

UICollectionView inside a UITableViewCell -- dynamic height?

Note :

TableViewCell height is based on collectionview content size i.e. if same tableCell have any other UI component other than collectionview or there is top bottom margin for collectionView then it won't be calculated. For this, you can create multiple cells in which one cell only contain collectionview (Best Approach for now) or you can return your actual tableview cell height in systemLayoutSizeFitting by calculation.

回答2:

how to give height to cell accorting to text in swift

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat
{
    let message = "Swift is a powerful and intuitive programming language for macOS, iOS, watchOS and tvOS. Writing Swift code is interactive and fun, the syntax is concise yet expressive, and Swift includes modern features developers love."


    let font = UIFont.systemFont(ofSize: 12.0)
    let height = heightForLabel(text: message, font: font, width: self.view.bounds.width )

    if height > 40 {
        return height  
    } else {
        return 40.0;
    }
}


func heightForLabel(text:String, font:UIFont, width:CGFloat) -> CGFloat
{
    let label:UILabel = UILabel(frame: CGRect(x:0,y: 0,width:width,height:CGFloat.greatestFiniteMagnitude))
    label.numberOfLines = 0
    label.lineBreakMode = NSLineBreakMode.byWordWrapping
    label.font = font
    label.text = text

    label.sizeToFit()
    return label.frame.height
}