Question

我在我的应用程序中使用ViewController。在ViewController中，我尝试使用textfield popOver tableview。但有错误

这是我的代码popUp：

   Func textFieldShouldBeginEditing(textField: UITextField) ->  Bool{      

    if (textField == paymentTextField){
        var paymentVC = MasterPaymentTableViewController()
        paymentVC.modalPresentationStyle = .Popover

        paymentVC.preferredContentSize = CGSizeMake(300, 500)

        let popOverPresentationVC = paymentVC.popoverPresentationController

        popOverPresentationVC?.delegate = self
        popOverPresentationVC?.permittedArrowDirections = .Down

        popOverPresentationVC?.sourceView = textField as UIView

       self.navigationController?.presentViewController(paymentVC, animated: true, completion: nil)

       return false
    }
  }

代码中出现此错误：

import UIKit
import CoreData

class MasterPaymentTableViewController: UITableViewController {

var myList : Array<AnyObject> = []
var appDel : AppDelegate!
var context : NSManagedObjectContext!

override func viewDidLoad() {
   super.viewDidLoad()


}

override func viewDidAppear(animated: Bool) {
   appDel = UIApplication.sharedApplication().delegate as! AppDelegate
   context = appDel.managedObjectContext

   let freq = NSFetchRequest(entityName: "PayMethod")

   myList = context.executeFetchRequest(freq, error: nil)!
   tableView.reloadData()
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
   // Dispose of any resources that can be recreated.
}

// MARK: - Table view data source

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {

  return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

return myList.count
}


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

    let cellID : String = "Cell"
    // ERROR AT HERE : unexpectedly found nil while unwrapping an Optional value
    var cell = tableView.dequeueReusableCellWithIdentifier(cellID) as! UITableViewCell
    // -------------
    if let ip = indexPath {
    var myObject : NSManagedObject = myList[ip.row] as! NSManagedObject

    let title = myObject.valueForKeyPath("paymentName") as! String

    cell.textLabel!.text = title
}


return cell
}

但是，如果我直接打开tableView而不是popOver，它的工作正常

任何解决方案？ THX

Answer 1

试试这个：

override func viewDidLoad() {
   super.viewDidLoad()

   tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "Cell")
}

并使用dequeueReusableCellWithIdentifier:forIndexPath:方法而不是dequeueReusableCellWithIdentifier：

let cell = tableView.dequeueReusableCellWithIdentifier(cellID, forIndexPath:indexPath)

PopOver TableView，Swift IOS 8中的单元格错误

1 个答案: