我有一个 tableView,我想在其中显示我的评论,例如 instagram 和许多其他社交网络的表现。帖子下方有 3 条评论,这里有一张图片来解释:
正如您从该图片中看到的那样,顶部是帖子,然后是标题,最后是 3 条最新评论。
我在我的应用程序中添加了一个评论系统,当我点击评论图标时我可以查看所有评论,我被重定向到新的 VC。
当我添加标题时,每个帖子都有一个 UUID,所以我认为这可以在某种程度上帮助将评论连接到帖子!
但现在我正在寻求实现这一目标。
到目前为止,我已经在帖子下方的 Storyboard 中添加了 3 个 UIlabel,然后我为这些标签创建了一个集合 outlet。现在在我的表格 View 中,我有一个获取最新 3 条评论的查询:
var commentUsername = [String]()
var commentArray = [String]()
let Commentquery = PFQuery(className: "Comments")
Commentquery.whereKey("toPost", containedIn: self.uuidArray)
Commentquery.addDescendingOrder("createdAt")
Commentquery.limit = 3
Commentquery.findObjectsInBackgroundWithBlock({ (objects:[PFObject]?, error:NSError?) -> Void in
if error == nil {
self.commentUsername.removeAll(keepCapacity: false)
self.commentArray.removeAll(keepCapacity: false)
for object in objects! {
self.commentArray.append(object.objectForKey("comment") as! String)
self.commentUsername.append(object.objectForKey("username") as! String)
}
tableView.reloadData
}
})
下面是我在 CellForRowAtIndexPath 中显示它们的方式:
var counter = (indexPath.row * 3)
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! NewsFeedTableViewCell
for comments in cell.threeComments{
comments.text = commentArray[counter++]
comments.sizeToFit()
}
正是在“comments.text = commentArray[counter++]”这一行,我得到了数组索引超出范围。
我猜我收到这个错误是因为它要么返回 nil 因为没有对该照片的评论,要么没有至少 3 条评论来填充 UILabels...这就是我有一段时间遇到的困难现在,如果有人知道如何修复或更正可能的“可选”查询或一些很棒的东西!!
如需进一步说明,请在下方评论。
提前致以最诚挚的问候和感谢!
完整代码:
var usernameArray = [String]()
var profilePicture = [PFFile]()
var dateArray = [NSDate?]()
var postArray = [PFFile]()
var titleArray = [String]()
var uuidArray = [String]()
var followArray = [String]()
var commentUsername = [String]()
var commentArray = [String]()
override func viewDidLoad() {
super.viewDidLoad()
loadPosts()
}
func loadPosts() {
let followQuery = PFQuery(className: "Follows")
followQuery.whereKey("follower", equalTo: PFUser.currentUser()!.username!)
followQuery.findObjectsInBackgroundWithBlock ({ (objects:[PFObject]?, error:NSError?) -> Void in
if error == nil {
self.followArray.removeAll(keepCapacity: false)
for object in objects! {
self.followArray.append(object.valueForKey("following") as! String)
}
self.followArray.append(PFUser.currentUser()!.username!)
let query = PFQuery(className: "Posts")
query.whereKey("username", containedIn: self.followArray)
query.limit = self.page
query.addDescendingOrder("createdAt")
query.findObjectsInBackgroundWithBlock({ (objects:[PFObject]?, error:NSError?) -> Void in
if error == nil {
self.usernameArray.removeAll(keepCapacity: false)
self.profilePicture.removeAll(keepCapacity: false)
self.dateArray.removeAll(keepCapacity: false)
self.postArray.removeAll(keepCapacity: false)
self.titleArray.removeAll(keepCapacity: false)
self.uuidArray.removeAll(keepCapacity: false)
for object in objects! {
self.usernameArray.append(object.valueForKey("username") as! String)
self.profilePicture.append(object.valueForKey("profilePicture") as! PFFile)
self.dateArray.append(object.createdAt)
self.postArray.append(object.valueForKey("image") as! PFFile)
self.titleArray.append(object.valueForKey("caption") as! String)
self.uuidArray.append(object.valueForKey("uuid") as! String)
}
let Commentquery = PFQuery(className: "Comments")
Commentquery.whereKey("toPost", containedIn: self.uuidArray)
Commentquery.addDescendingOrder("createdAt")
Commentquery.limit = 3
Commentquery.findObjectsInBackgroundWithBlock({ (objects:[PFObject]?, error:NSError?) -> Void in
if error == nil {
self.commentUsername.removeAll(keepCapacity: false)
self.commentArray.removeAll(keepCapacity: false)
for object in objects! {
self.commentArray.append(object.objectForKey("comment") as! String)
self.commentUsername.append(object.objectForKey("username") as! String)
}
self.tableView.reloadData()
}else {
print(error?.localizedDescription)
}
})
} else {
print(error!.localizedDescription)
}
})
} else {
print(error!.localizedDescription)
}
})
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return uuidArray.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
var counter = (indexPath.row * 3)
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! NewsFeedTableViewCell
for comments in cell.threeComments{
comments.text = commentArray[counter++]
comments.sizeToFit()
}
}
}
最佳答案
在 tableview 函数 (CellForRowAtIndexPath) 内,indexPath.row 给出当前单元格索引号,无需使用循环进行迭代,如果需要 3 个单元格,则必须在
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return commentArray.count // you can set static number 3 here, instead of set 'commentArray.count'
}
.
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! NewsFeedTableViewCell
comments.text = commentArray[indexPath.row]
comments.sizeToFit()
}
你可以这样改变你的循环
for (index, comments) in cell.threeComments {
comments.text = commentArray[index]
comments.sizeToFit()
}
关于ios - 数组索引超出范围,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35785081/