Swift 2 TableView Sorting

Question

I have an iOS project I'm working on in Xcode 7 using Swift 2. I have an array called details with a dictionary which includes a String and an Int value. The Int is called cellOrder in the Class and the idea is to sort the details array in a TableView with a sort based on the cellOrder Int value.

The array shows the String values which are names. I looked here to try and implement this into my project with no success.

Here is my array:

// Array of data for the TableView
var details = [ProjectDetails]()

Here is my TableView Code:

func numberOfSectionsInTableView(tableView: UITableView) -> Int {

    return 1

}

func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

    return details.count

}

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell

    cell.textLabel!.text = details[indexPath.row]        

    return cell

}

How do I do the sort and where would I put the code, ViewDidLoad() or maybe cellForRowAtIndexPath?

UPDATE:

My ViewDidLoad():

override func viewDidLoad() {
    super.viewDidLoad()

    // TableView Sorting
    details.sortInPlace({$0.cellOrder < $1.cellOrder})

    tableView.delegate = self

    ...

}

Update 2:

My ProjectDetails class for the array data is:

import UIKit

class ProjectDetails: NSObject, NSCoding {

    // MARK: Properties

    var fileName: String
    var cellOrder: Int

    ...

}

diatrevolo · Accepted Answer · 2016-02-02T19:56:02.060

3

To sort the array you would just do details.sortInPlace({$0.cellOrder < $1.cellOrder}) in viewDidLoad, or you could use details.sort({$0.cellOrder < $1.cellOrder})[indexPath.row] in cellForRowAtIndexPath, but that could prove dangerous if you do not keep track of your array.

One will sort the array in place, one will return a sorted immutable array.

If you insist on sorting immutably (has its pros and cons beyond this scope) assign it to another array and use that in your logic.

edited Feb 02 '16 at 19:56

answered Feb 02 '16 at 19:50

diatrevolo

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I added a new item to the array with a `cellOrder` of 0 and reloaded the `TableView` but it kept the old sort based on the `IndexPath`. It was the only one with a 0 as the `cellOrder`. – ChallengerGuy Feb 02 '16 at 20:02
Once you sort, you need to call `reloadData()` on the UITableView. This is not necessary after the sort in viewDidLoad, since this happens before the tableview gets populated. – diatrevolo Feb 02 '16 at 20:03
I put it in my `ViewDidLoad`. It was the first item in it. – ChallengerGuy Feb 02 '16 at 20:05
Please update your code in the original post to avoid having the debug lost in the comments. I'll have a look there. – diatrevolo Feb 02 '16 at 20:06

score 1 · Answer 2 · answered Feb 02 '16 at 19:50

You must sort the itens in this array details[], after that, you can call tableView.reloadData() to reload the info.

In the cellForRowAtIndexPath you must just take the data to fill the cell, so NO SORT THERE!

Sort anywhere else, before call the function to reload.

Swift 2 TableView Sorting

2 Answers2