我在社交网络应用程序方面取得了一些进展。我遇到了一个问题。我有一个ViewController，它提供了一个填充了我的解析数据库中的内容的TableView。在单元格中，我有一个RSVP按钮，它应该在点击时将基于indexPath的RSVP发送到数据库，并在再次单击时删除。我相信我的逻辑是正确的，然而，我一直收到错误：
上一次操作后操作无效。
我放置了一个断点来查找崩溃的原因，我发现它发生在rsvpButtonClicked IBOutlet函数中的addUniqueObject行。
有人能帮助我吗？我的代码如下。
import UIKit
import CoreLocation
class MainFeedViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
@IBOutlet var eventsTable: UITableView!
var user = PFUser.currentUser()
var refresher: UIRefreshControl!
var eventId = [String]()
var eventNames = [String]()
var eventCity = [String]()
var imageFiles = [PFFile]()
var getEventsQuery = 0
var userRsvps = [NSArray]()
var rsvp = 0
override func viewDidLoad() {
super.viewDidLoad()
getuserlocation()
getTodayDate()
}
override func viewWillAppear(animated: Bool) {
refreshControl()
//getMyRsvps()
}
override func viewDidAppear(animated: Bool) {
let timer = NSTimer.scheduledTimerWithTimeInterval(2.0, target: self, selector: "eventQuery", userInfo: nil, repeats: false)
}
func getMyRsvps() {
var getRsvps = PFUser.query()
getRsvps.whereKey("objectId", equalTo: user.objectId)
getRsvps.whereKeyExists("myrsvp")
getRsvps.findObjectsInBackgroundWithBlock {
(objects: [AnyObject]!, error: NSError!) -> Void in
if error == nil {
self.userRsvps.append(objects)
}
}
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = self.eventsTable.dequeueReusableCellWithIdentifier("mainFeedContent") as MainFeedContentTableViewCell
cell.eventName.text = eventNames[indexPath.row]
imageFiles[indexPath.row].getDataInBackgroundWithBlock{
(imageData: NSData!, error: NSError!) -> Void in
if error == nil {
let image = UIImage(data: imageData)
cell.eventImage.image = image
}
}
cell.rsvpButton.tag = indexPath.row
cell.rsvpButton.addTarget(self, action: "rsvpButtonClick:", forControlEvents: UIControlEvents.TouchUpInside)
return cell
}
@IBAction func rsvpButtonClick(sender: UIButton) {
var senderButton = sender
println("Current row \(senderButton.tag)")
var tempObject = eventId[senderButton.tag]
println("\(tempObject)")
PFUser.currentUser().addUniqueObject(tempObject, forKey: "myrsvp")
PFUser.currentUser().saveInBackground()
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return eventId.count
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let mainViewIdentifier = "showDetail"
if segue.identifier == mainViewIdentifier {
if let destination = segue.destinationViewController as? DetailViewController {
if let feedIndex = eventsTable.indexPathForSelectedRow()?.row {
destination.eventNames = eventNames[feedIndex]
destination.eventId = eventId[feedIndex]
destination.eventImagesFile = imageFiles[feedIndex]
}
}
}
}
func eventQuery() {
let getEventsQuery = PFQuery(className: "Events")
getEventsQuery.whereKey("eventLocation", nearGeoPoint: user["location"] as PFGeoPoint, withinMiles: user["preferredDistanceEvents"] as Double)
getEventsQuery.limit = 16
getEventsQuery.findObjectsInBackgroundWithBlock {(objects: [AnyObject]!, error: NSError!) -> Void in
if error == nil {
println("Successfully retrieved \(objects.count) events")
for object in objects {
self.eventId.append(object.objectId)
self.eventNames.append(object["eventName"] as String)
self.eventCity.append(object["eventCity"] as String)
self.imageFiles.append(object["eventPicture"] as PFFile)
self.eventsTable.reloadData()
}
} else {
println(error)
}
}
}
func refreshControl() {
refresher = UIRefreshControl()
refresher.attributedTitle = NSAttributedString(string: "Pull to refresh")
refresher.addTarget(self, action: "refresh", forControlEvents: UIControlEvents.ValueChanged)
self.eventsTable.addSubview(refresher)
}
/*
func scrollViewDidEndDragging(scrollView: UIScrollView, willDecelerate decelerate: Bool) {
var height: CGFloat = scrollView.frame.size.height
var contentYoffset: CGFloat = scrollView.contentOffset.y
var distanceFromBottom: CGFloat = scrollView.contentSize.height - contentYoffset
if distanceFromBottom <= height {
println("End of Table")
refresh()
}
}
*/
func refresh() {
self.getEventsQuery++
if self.getEventsQuery < self.eventId.count {
let refreshEventsQuery = PFQuery(className: "Events")
refreshEventsQuery.whereKey("location", nearGeoPoint: user["location"] as PFGeoPoint, withinMiles: user["preferredDistanceEvents"] as Double)
refreshEventsQuery.whereKey("objectId", notContainedIn: eventId)
refreshEventsQuery.limit = 4
refreshEventsQuery.findObjectsInBackgroundWithBlock {(objects: [AnyObject]!, error: NSError!) -> Void in
if error == nil {
println("Successfully retrieved \(objects.count) events")
for object in objects {
self.eventNames.append(object["eventName"] as String)
self.eventCity.append(object["City"] as String)
self.imageFiles.append(object["eventPicture"] as PFFile)
self.eventId.append(object.objectId)
self.eventsTable.reloadData()
}
} else {
println(error)
}
}
} else {
println("No More Events. Sorry")
}
self.refresher.endRefreshing()
}
func getuserlocation() {
PFGeoPoint.geoPointForCurrentLocationInBackground { (geopoint: PFGeoPoint!, error: NSError!) -> Void in
if error == nil {
self.user["location"] = geopoint
self.user.saveInBackground()
}
}
}
func getTodayDate(){
var today = NSDate()
var calendar = NSCalendar.currentCalendar()
var flags = NSCalendarUnit.HourCalendarUnit | NSCalendarUnit.MinuteCalendarUnit
var components = calendar.components(flags, fromDate: today)
var hour = components.hour
var minutes = components.minute
println("Today is \(today). The time is \(hour):\(minutes)")
}
}
答案 0 :(得分：0)
我认为这是解析中的一个错误（在与JS共享的代码中，因为我已经遇到了问题）。具体而言，当混合添加和删除PFObject方法来操作数组列时，会出现此失败。
我已经使用了以下两种解决方法并取得了一些成功：
addToColAndSave和removeFromColAndSave便利方法。如果你已经打过其中一个，请不要打电话给对方，直到保存完成。get，iOS中的objectForKey:）来获取内存中的数组，然后本地操作它。使用sdk setter更新对象。