Transfer data from a UITableCellView and UITableView - ios

Question

I have a UITableViewController with its own class HomeVC, containing multiple Cells, one of which uses its own class NewsFeedCell. This cell contains a vertical UIScrollView that displays pics. I want the user to, when he clicks the the row, trigger a segue to a VC with the picture. I created a currentPage variable in NewsFeedCell class, which obviously shows which page, and which picture, is the UIScrollView showing.
In the HomeVC, i have this:
class HomeVC: UITableViewController {
(...)
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
(...)
if indexPath.row == 0 { //The cell containing the UIScrollView
print(NewsFeedCell.currentPage) // I used "print" to simply the shown code
}
}
}
The problem is that xcode gives me an error saying Instance member "currentPage" cannot be used on type "NewsFeedCell".
I tried printing the value of currentPage to the console in the code of NewsFeedCell, and it worked.
Btw, the variable is declared inside the NewsFeedCell and has its first value assigned under awakeFromnNib() to 0, and the second time under:
func scrollViewDidEndScrollingAnimation(_ scrollView: UIScrollView){
currentPage = Int(floor((scrollView.contentOffset.x - cellWidth / 2) / cellWidth)) + 1
print(currentPage)
}
Please HELP!

Answer 1

It sounds like you created currentPage as an instance variable, meaning that each object of type NewsFeedCell has its own version. To access it, you have to have a reference to an individual NewsFeedCell, like this:
var myCell = NewsFeedCell()
print(myCell.currentPage)
and its value will be different for every cell. If you want there to be only a single currentPage for all NewsFeedCells, you declare it as static, like this (in the NewsFeedCell class):
static var currentPage: Int = 0
then you can access it using NewsFeedCell.currentPage as you have been.
The reason you were able to print(currentPage) from a function inside of NewsFeedCell is that that function is an instance method. Each instance has its own copy, and it prints the currentPage for the specific instance that the method was called on.
It's not quite clear to me what exactly you're trying to do with currentPage, so I'm not sure whether you want a static variable or an instance variable. In general, if you want there to be a single version of the variable that's accessible from anywhere, make it static. If you want each cell to have its own value, make it a regular instance variable.