Passing data to collectionViewCell - ios

Question

I'm want to use some custom struct in my collection view cell. I get the data from my API service and trying to pass it to my custom collection view cell.
I found couple answers but I still couldn't figure out how to do
Here is where I get the actual data:
func FetchFormData(linkUrl: String) {
let parameters: [String: AnyObject] = [:]
let postString = (parameters.flatMap({ (key, value) -> String in
return "\(key)=\(value)"
}) as Array).joined(separator: "&")
let url = URL(string: linkUrl)!
var request = URLRequest(url: url)
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.httpMethod = "POST"
request.httpBody = postString.data(using: .utf8)
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else {
print("error=\(String(describing: error))")
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(String(describing: response))")
}
let responseString = String(data: data, encoding: .utf8)
let contentData = responseString?.data(using: .utf8)
do {
let decoder = JSONDecoder()
self.formData = try decoder.decode(FormModel.self, from: contentData!)
} catch let err {
print("Err", err)
}
DispatchQueue.main.async {
//here is the where I reload Collection View
self.collectionView.reloadData()
}
}
task.resume()
}
Also here I'm trying to pass data to the cell:
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! BaseFormCollectionViewCell
cell.backgroundColor = .green
//Data could be print out here
print(self.formData?.components?[indexPath.row])
cell.formComponent = (self.formData?.components?[indexPath.row])!
return cell
}
The actual problem is starting into my cell class
class BaseFormCollectionViewCell: UICollectionViewCell {
var formComponent: FormComponent!{
didSet {
//data can be print out here
print("Passed value is: \(formComponent)")
}
}
override init(frame: CGRect) {
super.init(frame: frame)
//this part is always nill
print(formComponent)
}
}
As you guys can see in the code It's going well until my collection view cell.
It should be a lot more simple but I couldn't figure out what's going on and Why its happening.

Answer 1

Modify your cell class as
class BaseFormCollectionViewCell: UICollectionViewCell {
var formComponent: FormComponent!{
didSet {
//this is unnecessary. You can achieve what u want with a bit more cleaner way using configure function as shown below
//data can be print out here
print("Passed value is: \(formComponent)")
}
}
override init(frame: CGRect) {
super.init(frame: frame)
//this part is always nill
print(formComponent)
}
func configure() {
//configure your UI of cell using self.formComponent here
}
}
finally
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! BaseFormCollectionViewCell
cell.backgroundColor = .green
//Data could be print out here
print(self.formData?.components?[indexPath.row])
cell.formComponent = (self.formData?.components?[indexPath.row])!
(cell as! BaseFormCollectionViewCell).configure()
return cell
}
Look for (cell as! BaseFormCollectionViewCell).configure() in cellForItemAt thats how u trigger the UI configuration of cell after passing data to cell in statement above it.
Quite frankly u can get rid of didSet and relay on configure as shown
Hope it helps