How to pass data through table views - swift

Question

my data structure sample..
Sports
Bat-and-ball
Baseball
Softball
Cricket
Hockey
Field Hockey
Ice Hockey
Roller Hockey
Engineering
Computer Science
Software Engineer
Electrical Engineer
Here I have three level data as you can see . but by default in tableview it provides only upto 2 level. how can i display the third level data.
I am only able to show the 1st level data in sections and second level data in rows using customcell. now where to display the third level data. so that i can iterate based on number of rows..
my screen should be like that..

Answer 1

There are plenty of ways to do it.
I will list a couple of them later.
But first you might think about whether it is a good user experience to show 3 levels of data in one table view. It might be difficult for the user to navigate through it.
So these are some options.
Show the top level data (let's call it a category) in a selector(dropdown) and then in a table view just have two levels (sections and rows) for the selected category.
Here is an example of such dropdown view:
https://github.com/PhamBaTho/BTNavigationDropdownMenu
If you really need to show a list with 3 levels of data you can have a table view, which will show the top level data as a section and second level as a row. For each row the corresponding cell will contain inside a table view (or might be just a stack view) showing just the rows for the 3rd level.

Answer 2

you can add table in custom cell and 2nd and third level data can display on that inner table.

Answer 3

This code ran beautifully on my device.
Storyboard
TableViewController1
import UIKit
class TableViewController1: UITableViewController {
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return group1.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
cell.textLabel?.text = group1[indexPath.row].title
return cell
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "segue1" {
let indexPaths = self.tableView!.indexPathsForSelectedRows!
let indexPath = indexPaths[0] as NSIndexPath
let vc = segue.destinationViewController as! TableViewController2
vc.currentGroup = group1[indexPath.row].title
}
}
}
TableViewController2
import UIKit
class TableViewController2: UITableViewController {
var currentGroup: String?
var filteredData = [Data]()
override func viewDidLoad() {
super.viewDidLoad()
for data in group2 {
if data.group == currentGroup {
filteredData.append(data)
}
}
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return filteredData.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
cell.textLabel?.text = filteredData[indexPath.row].title
return cell
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "segue2" {
let indexPaths = self.tableView!.indexPathsForSelectedRows!
let indexPath = indexPaths[0] as NSIndexPath
let vc = segue.destinationViewController as! TableViewController3
vc.currentGroup = group2[indexPath.row].title
}
}
}
TableViewController3
import UIKit
class TableViewController3: UITableViewController {
var currentGroup: String?
var filteredData = [Data]()
override func viewDidLoad() {
super.viewDidLoad()
for data in group3 {
if data.group == currentGroup {
filteredData.append(data)
}
}
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return filteredData.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
cell.textLabel?.text = filteredData[indexPath.row].title
return cell
}
}
Data Class
import Foundation
class Data {
var title: String
var group: String?
init (title: String, group: String?) {
self.title = title
self.group = group
}
}
let group1 = [Data(title: "Sport", group: nil), Data(title: "Engineering", group: nil)]
let group2 = [Data(title: "Hockey", group: "Sport"), Data(title: "CS", group: "Engineering")]
let group3 = [Data(title: "Ice Hockey", group: "Hockey"), Data(title: "Software Engineer", group: "CS")]
P.S. I hate to make things complicated.
Happy hacking!