datasource.swift

private let CellDefaultHeight: CGFloat = 80.0
private let PlaceholderCellIdentifier = "PlaceholderCell"
private let ProfileCellIdentifier = "ProfileCell"

// MARK: - UITableView Protocol Conformance
extension ViewController: UITableViewDataSource {
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if viewModel.shouldShowPlaceholder {
            return Int(CGRectGetHeight(tableView.bounds) / CellDefaultHeight)
        } else {
            return viewModel.numberOfRows()
        }
    }
    
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        if viewModel.shouldShowPlaceholder {
            let cell = tableView.dequeueReusableCellWithIdentifier(PlaceholderCellIdentifier, forIndexPath: indexPath) as! PlaceholderCell
            
            return cell
        } else {
            let cell = tableView.dequeueReusableCellWithIdentifier(ProfileCellIdentifier, forIndexPath: indexPath) as! ProfileCell
            let cellViewModel = CellViewModel(profile: viewModel.profile(at: indexPath))
            cell.configureCell(with: cellViewModel)
            
            return cell
        }
    }
}