【发布时间】：2016-09-30 07:57:17
【问题描述】：
我在我的 Swift 项目中使用表格视图。问题在于表格视图单元格索引路径值。最初加载表时，索引值正常。但是，一旦我滚动表格视图，单元格索引路径就会发生变化，并且我从数据数组中获得的 id 是错误的。谷歌搜索结果是因为可重复使用的单元格之类的东西。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()
}
}
}
}
无论我向下滚动还是向上滚动，我都希望每个单元格的索引值保持不变。
【问题讨论】：
-
“单元格的索引值保持不变”是什么意思？你想让它是静态的吗？如果这就是你的意思，那么你不能那样做。 Cell的indexPath用于确定每个cell的位置。
-
`例如，我有 20 行，它最初显示 8 行（一次）。我在其中添加了 print(indexPath.row)。现在当我向下滚动时，它仍然会打印前行的 indexPath。
-
像这样：0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 10 9 8 7 6 5 4 3 2 1 0 8 9 10 1 0 7 8 9 10 11 12 13 14 15 16 17 10 9 8 7 6 5 4 3 2 1 0 7
-
所以，当您在 cellForRowAtIndexPath 中打印 indexPath.row 时，您遇到了问题，提示您。
-
阿里请去掉不需要的代码，只放cellForRowAtIndexPath的代码。因为不需要任何代码。
标签： ios swift tableview indexpath