Tableviewcells into specific header sections by classification (iOS) - ios

Question

I'm building a side project that involves a rather complicated table view. I've decided to take inspiration from Producthunt's app and have a header section for each date. But alas, this simple implementation is a bit harder than I thought it would be. For reference, I've attached photos below to show you what I'm trying to clone. This is from PH's app:
Examples
Implementation
See how there is a Today and Yesterday header section on the top with the date chillin beside it? I've asked peers and some of them suggested to try the [[array]] (array inside of array) approach. Section them out through enums and put them into specific arrays right? This is fine, but after awhile, you can see it getting out of hand. For example, here is some of my code below:
First, there's an enum for the diffrent date cases
enum dateCases {
case today
case yesterday
case twoDaysAgo
case threeDaysAgo
case fourDaysAgo
case fiveDaysAgo
case lastWeek
case lastMonth
case lastYear
case janurary
case feburary
case march
case april
case may
case june
case july
case augest
case september
case october
case november
case december
}
Then there's a struct for each class that needs these arrays in it:
struct dateCaseController {
var todayArray = [Objects]()
var yesterdayArray = [Objects]()
var twoDaysAgoArray = [Objects]()
var threeDaysAgoArray = [Objects]()
var fourDaysAgoArray = [Objects]()
var fiveDaysAgoArray = [Objects]()
var lastWeekArray = [Objects]()
var lastMonthArray = [Objects]()
var lastYearArray = [Objects]()
var januraryArray = [Objects]()
var feburaryArray = [Objects]()
var marchArray = [Objects]()
var aprilArray = [Objects]()
var mayArray = [Objects]()
var juneArray = [Objects]()
var julyArray = [Objects]()
var augestArray = [Objects]()
var septemberArray = [Objects]()
var octoberArray = [Objects]()
var novemberArray = [Objects]()
var decemberArray = [Objects]()
}
The objects all have dates inside of them we can use to analyze and section out the data. Each instance of this class has this struct.
After all of that, there's a function to section out the different objects into their specific arrays:
func anilyzeDateForDateCase(){
for object in objects {
let dateValue = (Logic for counting how many days has passed)
switch dateValue {
case 0:
print("")
case 1:
print("")
case 2:
print("")
case 3:
print("")
case 4:
print("")
case 5:
print("")
case 6:
print("")
ect.....
Conclusion
Thats going to be alot switch cases. You can tell by going this approach, the code will get out of hand quick. Using this approach would be nice if I had a small number of categories, but that is not the case. Not to mention after that, I will have load the table array according to section. I'm fine with doing that, but I'm wondering if this the correct approach to solving this problem? There has to be a simpler solution. Does anyone have experience with an implementation like this? Thank you.

Answer 1

As you correctly deduce, enum is not the way to go here. Apart from anything else, it is hard-coding UI choices into your data structures.
Can I suggest something along these lines:
import Foundation
// Define a `struct` that describes a date range.
// You may want to have convenience inits that don't just specify "days ago".
// You will create an array of these later...
struct DateRange {
var latestDaysAgo: Int
var earliestDaysAgo: Int
var description: String
// The important piece of this is that we can check if any given date
// is in `self` - we will use this later to `filter` by DateRange
func isDateInRange(_ date: Date) -> Bool {
let now = Date()
let oneDayInSeconds = 86400.0 // 60 * 60 * 24
let earliestDate = now.addingTimeInterval(Double(-self.earliestDaysAgo) * oneDayInSeconds)
let latestDate = now.addingTimeInterval(Double(-self.latestDaysAgo) * oneDayInSeconds)
return (date > earliestDate) && (date <= latestDate)
// NB - you REALLY want to do this with `Calendar` arithmetic
// but for clarity of the method, I'm just using 24 hour time differences
}
}
// Now construct your ranges. These can be extended after testing.
// They can also be overlapping.
let ranges: [DateRange] = [
DateRange(latestDaysAgo: 0, earliestDaysAgo: 1, description: "Today"),
DateRange(latestDaysAgo: 1, earliestDaysAgo: 2, description: "Yesterday"),
DateRange(latestDaysAgo: 2, earliestDaysAgo: Int.max, description: "Earlier"),
]
// This is whatever event struct you need - but they include the date
struct Event {
var date: Date
var payload: String // or whatever struct you want
}
// Create some random test data
let events: [Event] = [
Event(date: Date().addingTimeInterval(-100), payload: "abc"),
Event(date: Date().addingTimeInterval(-1000), payload: "abc"),
Event(date: Date().addingTimeInterval(-100000), payload: "abc"),
Event(date: Date().addingTimeInterval(-1000000), payload: "abc"),
]
// Now, the clever piece is combining `flatMap` & `filter` to get your sections:
let sections: [(DateRange, [Event])] = ranges.flatMap({
(dr: DateRange) in
let qualifyingEvents = events.filter({ dr.isDateInRange($0.date) })
return (dr, qualifyingEvents)
})
// Note that the order of ranges in `sections` is the same as the
// order that you chose in `ranges`.
// Check the sections are correct.
for (dr, es) in sections {
print("'\(dr.description)' has \(es.count) entries")
}
/* Output:
'Today' has 2 entries
'Yesterday' has 1 entries
'Earlier' has 1 entries
*/
You can now drive your UITableViewDataSource with sections. For example:
override func numberOfSections(in tableView: UITableView) -> Int {
return sections.count
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return sections[section].1.count
}
override func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
return sections[section].0.description
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: .subtitle, reuseIdentifier: "MyCellID")
let payload = sections[indexPath.section].1[indexPath.row].payload
cell.textLabel?.text = payload // or whatever...
return cell
}