Question

所以我有一个类型为Order的数组AllOrders，每次我想要刷新表我想清空AllOrders数组以从数据库中获取新的信息。但问题是我总是得到一个空数组。

我尝试了以下解决方案：

创造了一个延迟：当我把延迟时间延长到42秒时，这个工作有效，但谁可以等待42秒。来吧...
搜索了异步同步的转换器，但没有找到任何内容。

我知道firebase函数是异步的，这是造成我问题的原因。

    let userkey = sessionName.trimmingCharacters(in: .whitespaces)

    ref.child(userkey).child("handyman-orders").observeSingleEvent(of: .value, with: { snapshot in
        let enumerator = snapshot.children
        while let rest = enumerator.nextObject() as? FIRDataSnapshot {
            let newOrder = Orders()
            newOrder.service = (rest.childSnapshot(forPath: "Name").value! as? String)!
            newOrder.image = (rest.childSnapshot(forPath: "image").value! as? String)!
            newOrder.DeliveryType = (rest.childSnapshot(forPath: "DeliveryType").value! as? String)!
            newOrder.PickupInfo = (rest.childSnapshot(forPath: "PickupInfo").value! as? String)!
            newOrder.address = (rest.childSnapshot(forPath: "address").value! as? String)!
            allOrders.append(newOrder)
        }
        print("handyman  orders recieved")
    })

    ref.child(userkey).child("laundary-orders").observeSingleEvent(of: .value, with: { snapshot in
        let enumerator = snapshot.children
        while let rest = enumerator.nextObject() as? FIRDataSnapshot {
            let newOrder = Orders()
            newOrder.service = (rest.childSnapshot(forPath: "Name").value! as? String)!
            newOrder.image = (rest.childSnapshot(forPath: "image").value! as? String)!
            newOrder.DeliveryType = (rest.childSnapshot(forPath: "DeliveryType").value! as? String)!
            newOrder.PickupInfo = (rest.childSnapshot(forPath: "PickupInfo").value! as? String)!
            newOrder.address = (rest.childSnapshot(forPath: "address").value! as? String)!
            allOrders.append(newOrder)
            print("while laundary getorders",allOrders)
        }
        print("Laudanry orders recieved")

    })
    refreshControl.endRefreshing()
    ref.removeAllObservers()
}

我的刷新表函数是

 func refreshtable(_ sender: AnyObject) {
    allOrders.removeAll(keepingCapacity: false)
    getAllOrders()
    self.tableView.reloadData()
}

有人有什么想法吗？我将非常感激。感谢

firebase读取swift后数组为空

0 个答案: