Swift iOS：Firebase 分页

使用Firebase实现分页是在Swift iOS开发中常见的需求之一。分页功能可以使我们在处理大量数据时更加高效和灵活。在本文中，我们将学习如何使用Firebase实现分页功能，并通过一个案例代码来演示。

$ sudo gem install cocoapods
$ pod init

pod 'Firebase/Core'
pod 'Firebase/Database'

$ pod install

swift
import Firebase

swift
FirebaseApp.configure()

swift
var currentPageData: [String] = []
var nextPageToken: String?

swift
let ref = Database.database().reference().child("data")
ref.queryLimited(toFirst: 10).observeSingleEvent(of: .value, with: { snapshot in
    guard let data = snapshot.value as? [String: Any] else { return }
    self.currentPageData = Array(data.keys)
    self.nextPageToken = snapshot.children.allObjects.last?.key as? String
})

swift
func loadNextPage() {
    guard let nextPageToken = nextPageToken else { return }
    let ref = Database.database().reference().child("data")
    ref.queryStarting(atValue: nextPageToken).queryLimited(toFirst: 10).observeSingleEvent(of: .value, with: { snapshot in
        guard let data = snapshot.value as? [String: Any] else { return }
        let nextPageData = Array(data.keys)
        self.currentPageData += nextPageData
        self.nextPageToken = snapshot.children.allObjects.last?.key as? String
    })
}