iOS TableView在滚动上的索引值

我在我的Swift项目中使用表视图。问题是与表视图单元格索引路径值。当表最初加载时，索引值是正确的。但只要我滚动我的表视图，单元格索引路径改变，我从数据数组得到的id是错误的。谷歌的结果是，这是因为可重复使用的电池之类的东西。这是我的视图控制器代码:

//
//  ProjectsController.swift
//  PMUtilityTool
//
//  Created by Muhammad Ali on 9/23/16.
//  Copyright © 2016 Genetech Solutions. All rights reserved.
//
import UIKit
class ProjectsController: UIViewController {
    //MARK: Properties
    var ProjectsArray: Array<Project> = []
    @IBOutlet weak var ProjectsTableView: UITableView!
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        self.navigationController?.navigationBarHidden = true
        // Remove indenting of cell
        if self.ProjectsTableView.respondsToSelector(Selector("setSeparatorInset:")) {
            self.ProjectsTableView.separatorInset = UIEdgeInsetsZero
        }
        if self.ProjectsTableView.respondsToSelector(Selector("setLayoutMargins:")) {
            self.ProjectsTableView.layoutMargins = UIEdgeInsetsZero
        }
        self.ProjectsTableView.layoutIfNeeded()
        // Get projects
        getProjects()
    }
    override func viewWillAppear(animated: Bool) {
        self.navigationController?.navigationBarHidden = true
    }
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    /*
     // MARK: - Navigation
     // In a storyboard-based application, you will often want to do a little preparation before navigation
     override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
     // Get the new view controller using segue.destinationViewController.
     // Pass the selected object to the new view controller.
     }
     */
    // MARK: - TableView Datasource
    func numberOfSectionsInTableView(tableView: UITableView) -> Int
    {
        return 1
    }
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
    {
        return self.ProjectsArray.count
    }
    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        // print("clicked")
    }
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> ProjectTableViewCell {
        print(indexPath.row)
        let cell = tableView.dequeueReusableCellWithIdentifier("ProjectViewCell", forIndexPath:indexPath) as! ProjectTableViewCell
        // Remove indenting of cell
        cell.separatorInset = UIEdgeInsetsZero
        cell.layoutMargins = UIEdgeInsetsZero
        // Set project name
        cell.ProjectName.text = "((indexPath.row)+1). (self.ProjectsArray[indexPath.row].ProjectName)"
        // Set action button
        cell.ActionButton.tag = indexPath.row
        cell.ActionButton.addTarget(self, action: #selector(ProjectsController.projectActions(_:)), forControlEvents: .TouchUpInside)
        return cell
    }
    func reloadTableViewAfterDelay()
    {
        ProjectsTableView.performSelector(#selector(UITableView.reloadData), withObject: nil, afterDelay: 0.1)
    }
    @IBAction func projectActions(sender: UIButton) {
        let index = sender.tag
        let optionMenu = UIAlertController(title: nil, message: self.ProjectsArray[index].ProjectName, preferredStyle: .ActionSheet)
        // Report Progress
        let reportProgressAction = UIAlertAction(title: "Report Progress", style: .Default, handler: {
            (alert: UIAlertAction!) -> Void in
            self.performSegueWithIdentifier("ShowReportProgress", sender: sender)
        })
        // Cancel
        let cancelAction = UIAlertAction(title: "Cancel", style: .Cancel, handler: {
            (alert: UIAlertAction!) -> Void in
        })
        optionMenu.addAction(reportProgressAction)
        optionMenu.addAction(cancelAction)
        self.presentViewController(optionMenu, animated: true, completion: nil)
    }
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if let button = sender where segue.identifier == "ShowReportProgress" {
            let upcoming: ReportProgressController = segue.destinationViewController as! ReportProgressController
            print(self.ProjectsArray[button.tag].ProjectId)
            upcoming.ProjectId = self.ProjectsArray[button.tag].ProjectId
            upcoming.ProjectName = self.ProjectsArray[button.tag].ProjectName
        }
    }
    // MARK: Get Projects Function
    func getProjects() -> Void
    {
        var params = Dictionary<String,AnyObject>()
        params =  ["user_id":CFunctions.getSession("id")]
        WebServiceController.getAllProjects(params){ (type, response, message) -> Void in
            if (type == ResponseType.kResponseTypeFail)
            {
                // Show Error
                let alert = UIAlertController(title: "Error(s)", message:"Unable to load projects.", preferredStyle: .Alert)
                alert.addAction(UIAlertAction(title: "OK", style: .Default) { _ in })
                self.presentViewController(alert, animated: true){}
            }
            else
            {
                //debugPrint(response)
                if(response.count>0)
                {
                    self.ProjectsArray = response
                }
                else
                {
                    // Show Error
                    let alert = UIAlertController(title: "Error(s)", message:"No projects found.", preferredStyle: .Alert)
                    alert.addAction(UIAlertAction(title: "OK", style: .Default) { _ in })
                    self.presentViewController(alert, animated: true){}
                }
                self.reloadTableViewAfterDelay()
            }
        }
    }
}

我希望每个单元格的索引值是完整的，无论我向下或向上滚动

在你的iPhone屏幕上，你可以一次看到5个单元格。

第一次，当你加载tableView时cellForRowAtindexPAth方法会在第一个5点被调用细胞。

"正如你提到的，第一次加载tableView索引是正确的。"
现在当你向下滚动时，cellForRowAtIndexPath方法将被调用只有6和7。

"直到现在一切都很好，就像你说的。正如您所看到的，整个索引是完整的1、2、3、4、5、6、7。"
现在当你向上滚动{2 cells}。现在你可以看到屏幕上当前可见的单元格是1,2,3,4,5。

这里，cellForRowAtIndexPath方法将只对编号为2,1的单元格调用。

因为cell number 3,4,5已经加载在你的屏幕上了

所以,打印日志将是1,2,3,4,5,6,7,2,1。

您应该将UITableViewDelegate和UITableViewDataSource添加到您的类中。在viewDidLoad中设为ProjectsTableView.delegate = self。

您需要使用tableViewCell的层次结构获取按钮的indexPath。

 @IBAction func projectActions(sender: UIButton) {
  let button = sender as! UIButton
  let view = button.superview!
  let cell = view.superview as! UITableViewCell
  let indexPath = self.reloadTableViewAfterDelay.indexPathForCell(cell)
  let index = indexPath.row
}
 if let button = sender where segue.identifier == "ShowReportProgress" {
       let upcoming: ReportProgressController =  segue.destinationViewController as! ReportProgressController
       let view = button.superview!
       let cell = view.superview as! UITableViewCell
       let indexPath = self.reloadTableViewAfterDelay.indexPathForCell(cell)
       let index = indexPath.row
       print(self.ProjectsArray[index].ProjectId)
       upcoming.ProjectId = self.ProjectsArray[index].ProjectId
       upcoming.ProjectName = self.ProjectsArray[index].ProjectName
       }

需要获取按钮的indexPath使用tableViewCell的比下面的代码

func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
     return 10
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cellId: NSString = "Cell"
    let cell: UITableViewCell = tableView.dequeueReusableCellWithIdentifier(cellId as String)! as UITableViewCell
    let ActionButton : UIButton = cell.viewWithTag(10) as! UIButton
    ActionButton.addTarget(self, action: #selector(ViewController.projectActions(_:)), forControlEvents: UIControlEvents.TouchUpInside)
    return cell
}
@IBAction func projectActions(sender: UIButton) {
    let buttonPosition = sender.convertPoint(CGPointZero, toView: self.tableView)
    let indexPath = self.tableView.indexPathForRowAtPoint(buttonPosition)
    print(indexPath?.row)
}

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