我正在使用swift构建一个RSS阅读器,需要实现重新加载功能。

以下是我如何努力做到这一点。

class FirstViewController: UIViewController,
    UITableViewDelegate, UITableViewDataSource {

   @IBOutlet var refresh: UIScreenEdgePanGestureRecognizer
   @IBOutlet var newsCollect: UITableView

   var activityIndicator:UIActivityIndicatorView? = nil

   override func viewDidLoad() {
       super.viewDidLoad()
       self.newsCollect.scrollEnabled = true
      // Do any additional setup after loading the view, typically from a nib.

      if nCollect.news.count <= 2{
          self.collectNews()
       }
      else{
          self.removeActivityIndicator()
       }
      view.addGestureRecognizer(refresh)
   }



@IBAction func reload(sender: UIScreenEdgePanGestureRecognizer) {
    nCollect.news = News[]()
    return newsCollect.reloadData()
}

我得到:

财产的自我。刷新'未在super初始化。init调用

请帮助我理解手势识别器的行为。一个工作样例代码将是一个很大的帮助。

谢谢。


当前回答

你可以使用tableView的子类:

import UIKit

protocol PullToRefreshTableViewDelegate : class {
    func tableViewDidStartRefreshing(tableView: PullToRefreshTableView)
}

class PullToRefreshTableView: UITableView {

    @IBOutlet weak var pullToRefreshDelegate: AnyObject?
    private var refreshControl: UIRefreshControl!
    private var isFirstLoad = true

    override func willMoveToSuperview(newSuperview: UIView?) {
        super.willMoveToSuperview(newSuperview)

        if (isFirstLoad) {
            addRefreshControl()
            isFirstLoad = false
        }
    }

    private func addRefreshControl() {
        refreshControl = UIRefreshControl()
        refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
        refreshControl.addTarget(self, action: "refresh", forControlEvents: .ValueChanged)
        self.addSubview(refreshControl)
    }

    @objc private func refresh() {
       (pullToRefreshDelegate as? PullToRefreshTableViewDelegate)?.tableViewDidStartRefreshing(self)
    }

    func endRefreshing() {
        refreshControl.endRefreshing()
    }

}

1 -在接口构建器改变类你的tableView PullToRefreshTableView或创建一个PullToRefreshTableView编程

在你的视图控制器中实现PullToRefreshTableViewDelegate

当表视图开始刷新时,tableViewDidStartRefreshing(tableView: PullToRefreshTableView)将在视图控制器中被调用

4 -调用yourTableView.endRefreshing()来完成刷新

其他回答

斯威夫特5

private var pullControl = UIRefreshControl()

pullControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
        pullControl.addTarget(self, action: #selector(refreshListData(_:)), for: .valueChanged)
        if #available(iOS 10.0, *) {
            tableView.refreshControl = pullControl
        } else {
            tableView.addSubview(pullControl)
        }
// Actions
@objc private func refreshListData(_ sender: Any) {
        self.pullControl.endRefreshing() // You can stop after API Call
        // Call API
    }

你可以使用tableView的子类:

import UIKit

protocol PullToRefreshTableViewDelegate : class {
    func tableViewDidStartRefreshing(tableView: PullToRefreshTableView)
}

class PullToRefreshTableView: UITableView {

    @IBOutlet weak var pullToRefreshDelegate: AnyObject?
    private var refreshControl: UIRefreshControl!
    private var isFirstLoad = true

    override func willMoveToSuperview(newSuperview: UIView?) {
        super.willMoveToSuperview(newSuperview)

        if (isFirstLoad) {
            addRefreshControl()
            isFirstLoad = false
        }
    }

    private func addRefreshControl() {
        refreshControl = UIRefreshControl()
        refreshControl.attributedTitle = NSAttributedString(string: "Pull to refresh")
        refreshControl.addTarget(self, action: "refresh", forControlEvents: .ValueChanged)
        self.addSubview(refreshControl)
    }

    @objc private func refresh() {
       (pullToRefreshDelegate as? PullToRefreshTableViewDelegate)?.tableViewDidStartRefreshing(self)
    }

    func endRefreshing() {
        refreshControl.endRefreshing()
    }

}

1 -在接口构建器改变类你的tableView PullToRefreshTableView或创建一个PullToRefreshTableView编程

在你的视图控制器中实现PullToRefreshTableViewDelegate

当表视图开始刷新时,tableViewDidStartRefreshing(tableView: PullToRefreshTableView)将在视图控制器中被调用

4 -调用yourTableView.endRefreshing()来完成刷新

这就是我如何使用Xcode 7.2让它工作的,我认为这是一个主要的错误。我在我的UITableViewController中使用它在viewWillAppear中

refreshControl = UIRefreshControl()
refreshControl!.addTarget(self, action: "configureMessages", forControlEvents: .ValueChanged)
refreshControl!.beginRefreshing()

configureMessages()

func configureMessages() {
    // configuring messages logic here

    self.refreshControl!.endRefreshing()
}

正如你所看到的,我必须在设置我的UIRefreshControl之后调用configureMessage()方法,随后的刷新将正常工作。

对于拉刷新,我正在使用

DGElasticPullToRefresh

https://github.com/gontovnik/DGElasticPullToRefresh

安装

豆荚的DGElasticPullToRefresh

import DGElasticPullToRefresh

然后把这个函数放到你的swift文件中,然后从你的

override func viewWillAppear(_ animated: Bool)

     func Refresher() {
      let loadingView = DGElasticPullToRefreshLoadingViewCircle()
      loadingView.tintColor = UIColor(red: 255.0/255.0, green: 255.0/255.0, blue: 255.0/255.0, alpha: 1.0)
      self.table.dg_addPullToRefreshWithActionHandler({ [weak self] () -> Void in

          //Completion block you can perfrom your code here.

           print("Stack Overflow")

           self?.table.dg_stopLoading()
           }, loadingView: loadingView)
      self.table.dg_setPullToRefreshFillColor(UIColor(red: 255.0/255.0, green: 57.0/255.0, blue: 66.0/255.0, alpha: 1))
      self.table.dg_setPullToRefreshBackgroundColor(self.table.backgroundColor!)
 }

不要忘记在视图消失时删除引用

要删除拉刷新,请将此代码放入您的

重写func viewDidDisappear(_ animated: Bool)

override func viewDidDisappear(_ animated: Bool) {
      table.dg_removePullToRefresh()

 }

看起来就像

快乐编码:)

UIRefreshControl直接支持在每个UICollectionView, UITableView和UIScrollView(需要iOS 10+)!

这些视图中的每一个都有一个refreshControl实例属性,这意味着不再需要在你的滚动视图中添加它作为子视图,你所要做的就是:

@IBOutlet weak var collectionView: UICollectionView!

override func viewDidLoad() {
    super.viewDidLoad()
    
    let refreshControl = UIRefreshControl()
    refreshControl.addTarget(self, action: #selector(doSomething), for: .valueChanged)
    
    // this is the replacement of implementing: "collectionView.addSubview(refreshControl)"
    collectionView.refreshControl = refreshControl
}

@objc func doSomething(refreshControl: UIRefreshControl) {
    print("Hello World!")
    
    // somewhere in your code you might need to call:
    refreshControl.endRefreshing()
}

就我个人而言,我觉得将它作为滚动视图的属性比将它作为子视图添加更自然,特别是因为唯一合适的视图作为UIRefreshControl的父视图是一个滚动视图,即使用UIRefreshControl的功能只在与滚动视图一起工作时有用;这就是为什么这种方法应该更明显地设置刷新控件视图。

但是,你仍然可以选择基于iOS版本使用addSubview:

if #available(iOS 10.0, *) {
  collectionView.refreshControl = refreshControl
} else {
  collectionView.addSubview(refreshControl)
}