Display different arrays in collectionView after click on different rows in tableView - ios

Question

In my viewController i have tableView and collectionView.
And i try to display different arrays in collectionView when i click on different rows in tableView.
So when i click on firstRow in tableView, i want to display firstArray in collectionView, when i click on secondRow in tableView, i want to display secondArray in collectionView and when i click on thirdRow in tableView, i want to display thirdArray in collectionView.
How can i do this?
My test code:
class ViewController: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource, UITableViewDelegate, UITableViewDataSource {
#IBOutlet weak var collectionView: UICollectionView!
#IBOutlet weak var tableView: UITableView!
var tableArray: [String] = ["1", "2", "3"]
var secondArray: [String] = ["One", "Two"]
var thirdArray: [String] = ["Three", "Four"]
var fourthArray: [String] = ["Five", "Six"]
// TABLEVIEW
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return tableArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "tableCell", for: indexPath) as! TableCell
cell.tableLabel.text = tableArray[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print(indexPath)
}
// COLLECTIONVIEW
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return secondArray.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionCell", for: indexPath) as! CollectionCell
cell.collectionLabel.text = secondArray[indexPath.item]
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print(indexPath)
}
}
class TableCell: UITableViewCell {
#IBOutlet weak var tableLabel: UILabel!
}
class CollectionCell: UICollectionViewCell {
#IBOutlet weak var collectionLabel: UILabel!
}
I understand what need to use condition if, but how to use correct it?

Answer 1

You may add your arrays inside a dictionary (collectionData) using the index as key, in this way their lookup is totally dynamic and you don't need any if then else, so your code might be:
class ViewController: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource, UITableViewDelegate, UITableViewDataSource {
#IBOutlet weak var collectionView: UICollectionView!
#IBOutlet weak var tableView: UITableView!
var tableArray: [String] = ["1", "2", "3"]
// you may want to feed the dictionary directly with the arrays (feel free to remove them)
var collectionData: [Int: [String]] = [:]
var secondArray: [String] = ["One", "Two"]
var thirdArray: [String] = ["Three", "Four"]
var fourthArray: [String] = ["Five", "Six"]
override func viewDidLoad() {
super.viewDidLoad()
self.collectionData[0] = secondArray
self.collectionData[1] = thirdArray
self.collectionData[2] = fourthArray
}
func getCurrentArray() -> [String]? {
let currentRow = self.tableView.indexPathForSelectedRow?.row ?? 0
let array = self.collectionData[currentRow]
return array
}
// TABLEVIEW
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return tableArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "tableCell", for: indexPath) as! TableCell
cell.tableLabel.text = tableArray[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
self.collectionView.reloadData()
}
// COLLECTIONVIEW
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return self.getCurrentArray()?.count ?? 0
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionCell", for: indexPath) as! CollectionCell
cell.collectionLabel.text = self.getCurrentArray()?[indexPath.item]
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print(indexPath)
}
}
class TableCell: UITableViewCell {
#IBOutlet weak var tableLabel: UILabel!
}
class CollectionCell: UICollectionViewCell {
#IBOutlet weak var collectionLabel: UILabel!
}

Answer 2

You can create a dictionary and use it. And with the help of key you can easily fetch the different data from different table view cell.