每个单元格显示登录用户的相应评论和照片。他们加载了解析。
现在你想要Löschen按钮删除照片和评论。
不幸的是,这不起作用。当我点击按钮时没有任何反应
不幸的是,我对swift的理解很少,无法解决问题
查询有效,应用程序显示照片和Commons。查询和发布代码:
override func viewDidLoad() {
super.viewDidLoad()
super.viewDidLoad()
let query = PFQuery(className: "Post")
query.whereKey("username", equalTo: PFUser.current()?.username)
query.findObjectsInBackground(block: { (object, error) in
if let posts = object {
for post in posts{
print(posts)
self.comments.append(post["message"] as! String)
self.imageFile.append(post["imageFile"] as! PFFile)
self.tableView.reloadData()
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
})
}
这里是我尝试的“删除”功能代码:
@IBAction func remove(_ sender: Any) {
print("Entered remove")
let query = PFQuery(className: "Post")
query.whereKey("username", equalTo: PFUser.current()?.username)
query.findObjectsInBackground(block: { (object, error) in
if let posts = object {
print(posts)
for post in posts{
print(posts)
if let message = post["message"] as? String, let image = post["imageFile"] as? PFFile {
print("message and image read", message, image)
if let messageIndex = self.comments.index(of: message), let imageIndex = self.imageFile.index(of:image) {
self.comments.remove(at: messageIndex)
self.imageFile.remove(at: imageIndex)
}
}
self.tableView.reloadData()
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
})
}
输出:
我没有收到错误消息,也没有删除任何内容。谢谢您的帮助
您无权访问当前索引where和object id。因此,基于此,您可以轻松删除。
实现删除功能的更简单方法是为您的消息添加一个objectId数组:
self.ids.append(post.objectId)
当你想删除它时:
let query = PFQuery(className: "Post")
query.whereKey("objectId", equalTo: self.ids.index(of: indexPath.row))
// Make a query in background to only get the object that you want to delete
query.getFirstObjectInBackgroundWithBlock {
(object: PFObject?, error: NSError?) -> Void in
if error != nil || object == nil {
print("The getFirstObject request failed.")
} else if let object = object {
print("Successfully retrieved the object.")
object.deleteInBackground()
}
}
拥有代表同一个对象的不同数组并不是很好。因此,处理问题的更好方法是只为您的帖子提供一个数组
当你获取它时,你可以做类似的事情:
guard let user = PFUser.current() else { return }
let query = PFQuery(className: "Post")
query.whereKey("username", equalTo: user.username)
query.findObjectsInBackground(block: { (posts, error) in
if let posts = posts {
self.posts = posts
}
})
这样当你想在remove函数中删除它时:
if indexPath.row < self.posts.count {
self.posts[indexPath.row].deleteInBackground()
}