How do I create a custom UITableViewCell class in Swift? - ios

Question

I'm trying to follow along the following Using Auto Layout in UITableView for dynamic cell layouts & variable row heights top answer in Swift but for the IOS 7 version to mitigate some bugs in the IOS 8.
Right now, my custom cell class is:
class PostCell: UITableViewCell {
#IBOutlet var name: UILabel!
#IBOutlet var timestamp: UILabel!
#IBOutlet var postBody: UILabel!
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
}
In my Storyboard I set my custom class as the class for the cell. I don't know if I have to use my reuseIdentifier anywhere. I don't know how to get that working in the next piece of code.
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
var cell = PostCell()
var post = self.posts[indexPath.row]
cell.name.text = post.name
cell.timestamp.text = post.timestamp
cell.postBody.text = post.body
cell.setNeedsUpdateConstraints()
cell.updateConstraintsIfNeeded()
cell.bounds = CGRectMake(0.0, 0.0, CGRectGetWidth(feed.bounds), CGRectGetHeight(cell.bounds))
cell.setNeedsLayout()
cell.layoutIfNeeded()
var height = cell.contentView.systemLayoutSizeFittingSize(UILayoutFittingCompressedSize).height
height += 1.0
return height
}
I thought that would work, but when I call cell.name.text = post.name, I get an EXC_BAD_INSTRUCTION. I'm guessing the cell isn't properly hooked up to the storyboard somehow or something. How do I fix this?

Answer 1

The problem is that you don't understand how nibs work. You have set up your PostCell to be configured when it is loaded from its nib:
class PostCell: UITableViewCell {
#IBOutlet var name: UILabel!
}
So that means that name is nil - until this cell is instantiated from the nib, at which time the outlet will be hooked up. But then later you say:
var cell = PostCell()
But that is the wrong PostCell! You didn't load it from the nib; you just made one out of whole cloth. So since there was no nib-loading, the outlet (as you rightly suspect) was naturally never connected, and so cell.name is nil.
So the solution is: do not make one out of whole cloth. Load it from the nib.