Can you explain what the UITableViewDataSource protocol is in iOS and how it is used to display data in a table?

UITableViewDataSource is a protocol in iOS that defines methods for providing data and managing the content of a table (UITableView). It is responsible for what data is displayed and in what form within the table cells.

Main protocol methods:

• tableView(_:numberOfRowsInSection:) — returns the number of rows in a section.
• tableView(_:cellForRowAt:) — returns a cell (UITableViewCell) for a specific row, where data display is configured.

Usage:

1. A class (e.g., UIViewController) declares that it implements UITableViewDataSource.
2. Implements the required protocol methods.
3. Sets itself as the data source for the table: tableView.dataSource = self.

Example:

class MyViewController: UIViewController, UITableViewDataSource {
    let data = ["Apple", "Banana", "Cherry"]

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return data.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
        cell.textLabel?.text = data[indexPath.row]
        return cell
    }
}

Thus, UITableViewDataSource links data with the visual representation in the table.