CODEWITHSUNDEEP
iosswiftuicollectionview
209135
209135

Reputation: 517

Multiple Collection Views with in a viewController with different number of cells

There seems to be a similar question here but it didn't solve my problem.

I created two collectionViews in my viewController as follows : 

let y = self.view.frame.height
titleView  = UIView(frame : CGRect(x: 0 , y:  50 , width: self.view.frame.width, height: y - 100 ))

let middle = CGPoint(x: 10, y:   titleView.bounds.height/10)
let frame = CGRect(origin: middle , size: CGSize(width: self.view.frame.width - 20 , height: 70))
let layout = UICollectionViewFlowLayout()
fontCollection = UICollectionView(frame: frame, collectionViewLayout: layout)
fontCollection.dataSource = self
fontCollection.delegate = self
fontCollection.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "fontsIdentifier")
fontCollection.backgroundColor = UIColor.white
// Do any additional setup after

colorCollection  = UICollectionView(frame: frame, collectionViewLayout: layout)
//colorCollection.frame.origin.y = fontCollection.frame.origin.y + (2 * fontCollection.frame.height)
colorCollection.dataSource = self
colorCollection.delegate = self
colorCollection.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "colorsIdentifier")
colorCollection.backgroundColor = UIColor.white
// Do any additional setup after

These are my UICollectionViewDataSource methods :

func numberOfSections(in collectionView: UICollectionView) -> Int {
    collectionView.reloadData()
    collectionView.collectionViewLayout.invalidateLayout()
    return 1
}

public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    if(collectionView == self.colorCollection ){
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "colorsIdentifier", for: indexPath)
        cell.backgroundColor = .darkGray
        return cell
    } else {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "fontsIdentifier", for: indexPath)
        cell.backgroundColor = .gray
        return cell
    }
}

Then I use a segmented control to switch between the two collectionViews. Everything goes as desired upto this point.However when I want to allocate different number of cells to either collectionView I get this error :

UICollectionView received layout attributes for a cell with an index path that does not exist: {length = 2, path = 0 - 6}

This is my numberOfItemsInSection method

public func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {

     if(collectionView == self.colorCollection ){ return 9 }
     else if(collectionView == self.fontCollection ){  return 6  }

     return 0
}

Am I doing something wrong? What am I missing?

Upvotes: 4

Views: 1526

Answers (1)

209135
209135

Reputation: 517

As @Rajesh73 pointed out in the comment , the problem was in assigning one layout to both the collectionViews. So I gave the both collectionViews different layouts and it solved the problem.

Thus replacing 

  let layout =              UICollectionViewFlowLayout()
  fontCollection  =         UICollectionView(frame: frame, collectionViewLayout: layout)
  colorCollection  =        UICollectionView(frame: frame, collectionViewLayout: layout)

with 

  let fontsLayout =      UICollectionViewFlowLayout()
  fontCollection  =      UICollectionView(frame: frame,collectionViewLayout: fontsLayout)
  let colorsLayout =      UICollectionViewFlowLayout()
 colorsCollection  =     UICollectionView(frame: frame collectionViewLayout: colorsLayout)

solved the issue.

Upvotes: 3

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