Swift: How to Display Parsed JSON Data in CollectionView inside a TableView? - arrays

Question

I'm trying to display my data as this image.
My problem is that data displayed inside table view rows are all the same thing, while it should display all data of the array.
This is the code I used to display the collectionView inside the tableView:
var onlineNews = ["local", "Economy", "Variety", "international", "sport"]
var storedOffsets = [Int: CGFloat]()
var tableIndexPath: IndexPath!
#IBOutlet var listTableView: UITableView!
var tableIndex: Int = 0
var categoryResults = [JSON]() {
didSet {
listTableView.reloadData()
}
}
let requestManager = RequestManager()
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
for i in onlineNews {
requestManager.categoryList(sectionName: i)
}
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return onlineNews.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "itemCell", for: indexPath) as! NewsTableViewCell
tableIndex = indexPath.row
return cell
}
func tableView(_ tableView: UITableView,
willDisplay cell: UITableViewCell,
forRowAt indexPath: IndexPath) {
guard let tableViewCell = cell as? NewsTableViewCell else { return }
tableViewCell.setCollectionViewDataSourceDelegate(dataSourceDelegate: self, forRow: (indexPath as NSIndexPath).row)
tableViewCell.collectionViewOffset = storedOffsets[(indexPath as NSIndexPath).row] ?? 0
}
func tableView(_ tableView: UITableView,
didEndDisplaying cell: UITableViewCell,
forRowAt indexPath: IndexPath) {
guard let tableViewCell = cell as? NewsTableViewCell else { return }
storedOffsets[(indexPath as NSIndexPath).row] = tableViewCell.collectionViewOffset
}
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView,
numberOfItemsInSection section: Int) -> Int {
return categoryResults.count
}
func collectionView(_ collectionView: UICollectionView,
cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ColCell",
for: indexPath) as! NewsCollectionViewCell
cell.contentType.text = categoryResults[indexPath.row]["ContentType"].stringValue **// This is where I get the same values for all table view rows**
cell.sectionName.text = onlineNews[tableIndex]
return cell
}
I'm sure someone can absolutely help me with this as I know that it takes only a small tweak to make it work, but not sure where.
Update:
I have followed a way that I believe should work, which is to declare the JSON array to be like this [[JSON]], and then use categoryResults[collection.tag][indexPath.item]["ContentType"].stringValue to get to the value. However, it gives me "index out of range" message. Do you have any clue how can I solve the issue?
var onlineNews = ["local", "Economy", "Variety", "international", "sport"]
var storedOffsets = [Int: CGFloat]()
#IBOutlet var listTableView: UITableView!
var tableIndex: Int = 0
var categoryResults = [[JSON]]() { // updated
didSet {
listTableView.reloadData()
}
}
let requestManager = RequestManager()
override func viewDidLoad() {
super.viewDidLoad()
requestManager.resetCategory()
updateSearchResults()
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.updateSearchResults), name: NSNotification.Name(rawValue: "categoryResultsUpdated"), object: nil)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
for i in 0..<onlineNews.count {
requestManager.categoryList(sectionName: onlineNews[i])
}
}
func updateSearchResults() {
categoryResults = [requestManager.categoryResults] // updated
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return onlineNews.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "itemCell", for: indexPath) as! NewsTableViewCell
tableIndex = indexPath.row
return cell
}
func tableView(_ tableView: UITableView,
willDisplay cell: UITableViewCell,
forRowAt indexPath: IndexPath) {
guard let tableViewCell = cell as? NewsTableViewCell else { return }
tableViewCell.setCollectionViewDataSourceDelegate(dataSourceDelegate: self, forRow: (indexPath as NSIndexPath).row)
tableViewCell.collectionViewOffset = storedOffsets[(indexPath as NSIndexPath).row] ?? 0
}
func tableView(_ tableView: UITableView,
didEndDisplaying cell: UITableViewCell,
forRowAt indexPath: IndexPath) {
guard let tableViewCell = cell as? NewsTableViewCell else { return }
storedOffsets[(indexPath as NSIndexPath).row] = tableViewCell.collectionViewOffset
}
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView,
numberOfItemsInSection section: Int) -> Int {
return categoryResults[collectionView.tag].count // updated
}
func collectionView(_ collectionView: UICollectionView,
cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ColCell",
for: indexPath) as! NewsCollectionViewCell
cell.contentType.text = categoryResults[collectionView.tag][indexPath.row]["ContentType"].stringValue // updated
return cell
}
This the content of RequestManager class (where I call the API):
var categoryResults = [JSON]()
func categoryList(sectionName: String) {
let url = "http://mobile.example.com/api/Content?MobileRequest=GetCategoryNews&PageNo=1&RowsPerPage=10&Category=\(sectionName)&IssueID=0&Type=online"
print("this is the url \(url)")
Alamofire.request(url, method: .get).responseJSON{ response in
if let results = response.result.value as? [String:AnyObject] {
let items = JSON(results["Data"]?["OnlineCategoryNews"]! as Any).arrayValue
self.categoryResults += items
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "categoryResultsUpdated"), object: nil)
}
}
}
func resetCategory() {
categoryResults = []
}
deinit {
NotificationCenter.default.removeObserver(self)
}
Update 2:
And here is the method where the collectionView.tag is assigned. This is added to the tableViewCell class:
func setCollectionViewDataSourceDelegate
<D: protocol<UICollectionViewDataSource, UICollectionViewDelegate>>
(dataSourceDelegate: D, forRow row: Int) {
collectionView.delegate = dataSourceDelegate
collectionView.dataSource = dataSourceDelegate
collectionView.tag = row
collectionView.bounds.size.width = self.bounds.size.width
collectionView.reloadData()
}

Answer 1

Collection view delegate methods don't know context of their collection view. You should calculate onlineNews index depending on the collectionView instance instead of using indexPath.row, which is internal collection view index path.
Edit: better option (to avoid scrolling and layout issues) is to use single collection view, where cells are grouped in rows. If you don't want to make layout manager, you can achieve such layout by adding small, but very wide separator views between sections
Edit2:
cell.contentType.text = categoryResults[indexPath.row]["ContentType"].stringValue
uses local indexPath of this collection view. You could assign tag to tableViewCell.collectionView with a value of desired categoryResults index. Then you can use this tag as in categoryResults[collectionView.tag]