ios - Firebase + Swift 在 TableView 中删除行

Question

好的，我正在按照本教程 ( https://www.raywenderlich.com/139322/firebase-tutorial-getting-started-2 ) 使用 Firebase 删除 tableView 中的行，但它似乎不起作用。我的代码如下:

override func viewDidLoad() {
    super.viewDidLoad()
    configureDatabase() 
}

func configureDatabase() {
    self.ref = FIRDatabase.database().reference()
    if let user = FIRAuth.auth()?.currentUser {
        self.ref.child("mileage").queryOrderedByChild("user").queryEqualToValue(user.uid).observeEventType(.ChildAdded, withBlock: { (snapshot) in
            self.mileageDatabase.insert(snapshot, atIndex: 0)
            self.tableView.insertRowsAtIndexPaths([NSIndexPath(forRow: 0, inSection: 0)], withRowAnimation: .Automatic)

        })


    } else {

    }

}

override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
    if (editingStyle == UITableViewCellEditingStyle.Delete) {
        let row = self.mileageDatabase[indexPath.row]
        row.ref.removeValue()
        self.tableView.deleteRowsAtIndexPaths([NSIndexPath(forRow: indexPath.row, inSection: 0)], withRowAnimation: .Automatic)

    }
}

它抛出错误:

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid update: invalid number of rows in section 0. The number of rows contained in an existing section after the update (8) must be equal to the number of rows contained in that section before the update (8), plus or minus the number of rows inserted or deleted from that section (0 inserted, 1 deleted) and plus or minus the number of rows moved into or out of that section (0 moved in, 0 moved out).'

Answer 1

我认为这里 row.ref.removeValue() 有一个错误。您正在将 Array 与 Firebase 数据混合在一起。如果你只写:

mileageDatabase.remove[indexPath.row]
tableview.reloadData()

对我来说就是这样工作的。您必须捕获该行的用户 key 。我有一个像你的数组 (mileageDatabase = teste)，但我的变量存储在 sublcass (ChkList) 内的结构中。我就是这样做的。

override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {

if editingStyle == .delete {

        let user: ChkList = teste[indexPath.row]
        let uk = user.key
        print("Userkey: \(uk)")
        ref.child(uk!).removeValue()
}
}

这样您就可以从 Firebase 和表格 View 中删除数据。您可以在以下位置查看我的问题:Firebase: delete item from row (Swift 3)