Swift 5- Firebase-标题中按日期分组 [英] Swift 5- Firebase- Group by date in header
本文介绍了Swift 5- Firebase-标题中按日期分组的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我的主要目标是从Firebase数据库中获取日期，并将其用作部分标题，以便我可以在该标题下加载所有具有相同日期的事件.
My Main goal is to take the Date from the Firebase Database and use is as a section header so that i may load all the events that have the same date under that header.
我希望它显示在我的表格视图中:
I would like it to appear in my table view like this:
9月-标头
-2020年9月29日-sub标头
-September 29,2020 -sub header
-事件
-事件
-事件
-2020年9月30日-sub标头
-september 30, 2020 -sub header
-事件
-事件
-事件
这是我的主要View Controller.
This is my main View Controller.
import UIKit
import Foundation
import Firebase
import FirebaseDatabase
class EventsTableViewController: UIViewController {
var sectionNames: [String] = []
var events: [String: [EventsInfo]] = [:]
var datref: DatabaseReference!
var eventView = [EventsInfo]()
@IBOutlet weak var eventTableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
getEventsFromFirebaseDB()
}
deinit {
datref.removeAllObservers()
}
private func eventsFetched(_ eventData: [EventsInfo])
{
for event in eventData
{
guard let eventNameFirstChar = event.date.first else { continue }
if var eventsForKey = events["\(eventNameFirstChar)"]
{
eventsForKey.append(event)
events["\(eventNameFirstChar)"] = eventsForKey
}
else
{
// no users are stored in dictionary for key userNameFirstChar
events["\(eventNameFirstChar)"] = [event]
}
}
// sort dictionary keys and set it in sectionNames
sectionNames = events.map { $0.key }.sorted()
print (sectionNames)
}
private func getEventsFromFirebaseDB() {
datref = Database.database().reference().child("events")
datref.observe(DataEventType.value, with: { [weak self] (snapshot) in
guard snapshot.childrenCount > 0 else { return }
var events: [EventsInfo] = []
for event in snapshot.children.allObjects as! [DataSnapshot]
{
let object = event.value as? [String: AnyObject]
let title = object?["title"]
let place = object?["place"]
let info = object?["info"]
let date = object?["date"]
let time = object?["time"]
let event = EventsInfo(title: title as! String, place: place as! String, info: info as! String, time: time as! String, date: date as! String)
events.append(event)
}
self?.eventsFetched(events)
self?.eventTableView.reloadData()
})
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "showEvent"
{
if let indexPath = eventTableView.indexPathForSelectedRow
{
let destinationController = segue.destination as! EventsInfoViewController
let char = sectionNames[indexPath.section]
let event = events[char]![indexPath.row]
destinationController.EventsData = event
}
}
}
}
extension EventsTableViewController: UITableViewDataSource, UITableViewDelegate {
func numberOfSections(in tableView: UITableView) -> Int {
sectionNames.count
}
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
sectionNames[section]
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
let char = sectionNames[section]
return events[char]!.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = eventTableView.dequeueReusableCell(withIdentifier: "eventsCell") as! EventsTableViewCell
let char = sectionNames[indexPath.section]
let event = events[char]![indexPath.row]
cell.eventTitleLabel.text = event.title
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
performSegue(withIdentifier: "showEvent", sender: self)
}
这是我的EventsInfo文件
This is my EventsInfo File
import Foundation
class EventsInfo {
var title: String
var place: String
var info: String
var time: String
var date: String
init(title: String, place: String, info: String, time: String, date: String) {
self.title = title
self.place = place
self.info = info
self.time = time
self.date = date
}
}
推荐答案
我正在给出一个答案，希望它可以通过一个例子提供一些指导.请注意，这与Firebase无关-纯粹是tableView管理.
I am tossing out an answer in hopes it will provide some direction though an example. Note that none of this is related to Firebase - it's purely tableView management.
我们的应用程序列出了所有水果，其中标题标题是每个水果的名字
Our app is a list is fruits with section titles being the first name of each fruit
A
Apple
B
Banana
等
这是一个用于保存每个部分的数据的结构，然后是一个用于保存这些对象的类数组(tableView dataSource)
Here's a struct to hold each section's data and then a class array to hold those objects (the tableView dataSource)
struct FruitStruct {
var sectionTitle = ""
var fruitNameArray = [String]()
}
var fruitDataSource = [FruitStruct]()
然后让我们填充该数据
func setupDataSourceData() {
let fruitArray = ["Apple", "Pear", "Banana", "Bing Cherry", "Grape", "Orange", "Plum", "Watermelon", "Cantelope"]
let allFirstChars = fruitArray.map { String($0.prefix(1)) } //get all first chars for section titles
let sectionTitles = Array(Set(allFirstChars)).sorted() //eliminate dups and sort
//iterate over the unique section titles and get the fruits that are in that section
// sort and then craft structs to hold the title and the associated fruits
sectionTitles.forEach { firstChar in
let results = fruitArray.filter { $0.prefix(1) == firstChar }
let sortedFruits = results.sorted()
let fruit = FruitStruct(sectionTitle: firstChar, fruitNameArray: sortedFruits)
fruitDataSource.append(fruit)
}
//this code is to just output the data to console so you can see what it
// looks like. Remove it.
for fruitData in fruitDataSource {
print(fruitData.sectionTitle)
let fruits = fruitData.fruitNameArray
for fruitName in fruits {
print(" \(fruitName)")
}
}
}
最后，使用tableView委托方法从数据源填充tableView
lastly, the tableView delegate methods to populate the tableView from the dataSource
//
//handle sections
//
func numberOfSections(in tableView: UITableView) -> Int {
return self.fruitDataSource.count
}
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
let title = self.fruitDataSource[section].sectionTitle
return title
}
//
//handleTableView rows
//
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
let rowsInSection = self.fruitDataSource[section].fruitNameArray.count
return rowsInSection
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellReuseIdentifier", for: indexPath)
let text = self.fruitDataSource[indexPath.section].fruitNameArray[indexPath.row]
cell.textLabel?.text = text
return cell
}
这篇关于Swift 5- Firebase-标题中按日期分组的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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