如何从Swift中的viewController类中分离dataSource和delegate？

Question

我正在尝试从viewController中分离dataSource和delegate,以防止viewController变得混乱.我阅读了一些帖子,发现我可以像下面一样分开dataSource,创建一个类来表示dataSource:

import UIKit

class DataSource: NSObject, UITableViewDataSource, UITableViewDelegate {

    var movies = [String]()

    //MARK: - UITableViewDataSource
    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }

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

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        let cell = tableView.dequeueReusableCellWithIdentifier("cellIdentifier", forIndexPath: indexPath) as UITableViewCell


        cell.textLabel?.text =  movies[indexPath.row]

        return cell
    }

}

我的问题是:如果我想viewController在DataSource类中使用属性或调用类的方法,我该怎么办？例如,我想presentViewController在用户选择单元格时调用:

func tableView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

    //do something here

    presentViewController(viewController!, animated: true, completion: nil)
}

Answer 1

您可以处理选定的回调:

class DataSource: NSObject, UITableViewDataSource, UITableViewDelegate {

        var movies = [String]()
        private var selectedCallback = ((NSIndexPath)->Void)?

        func selectedItemAtIndex(callback:(NSIndexPath) -> Void) {
            selectedCallback = callback
        }
}

打回来:

func tableView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

    //do something here

    if let callback = selectedCallback {
       callback(indexPath)
    }
}

使用:

dataSource.selectedItemAtIndex() {
  [weak self] indexPath in
  // do something ...
  // presentViewController(viewController!, animated: true, completion: nil)
}