Reorder Realm Results in UITableView

ReorderingRealmResultsInTableView.swift

import UIKit
import RealmSwift

class Data: Object {
    dynamic var name = ""
    ...
    
    dynamic var order = 0 // 並べ替えのためのカラムが必要
}

class ViewController: UITableViewController {
    lazy var realm = try! Realm()
    var objects: Results<Data>!

    override func viewDidLoad() {
        super.viewDidLoad()
        
        objects = realm.objects(Data.self).sorted("order")
    }

    override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return objects.count
    }

    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath)
        ...

        return cell
    }

    override func tableView(tableView: UITableView, moveRowAtIndexPath sourceIndexPath: NSIndexPath, toIndexPath destinationIndexPath: NSIndexPath) {
        try! realm.write {
            let sourceObject = objects[sourceIndexPath.row]
            let destinationObject = objects[destinationIndexPath.row]

            let destinationObjectOrder = destinationObject.order

            if sourceIndexPath.row < destinationIndexPath.row {
                // 上から下に移動した場合、間の項目を上にシフト
                for index in sourceIndexPath.row...destinationIndexPath.row {
                    let object = objects[index]
                    object.order -= 1
                }
            } else {
                // 下から上に移動した場合、間の項目を下にシフト
                for index in (destinationIndexPath.row..<sourceIndexPath.row).reverse() {
                    let object = objects[index]
                    object.order += 1
                }
            }
　　　　　　　　
　　　　　　　　// 移動したセルの並びを移動先に更新
            sourceObject.order = destinationObjectOrder
        }
    }

    override func tableView(tableView: UITableView, shouldIndentWhileEditingRowAtIndexPath indexPath: NSIndexPath) -> Bool {
        return false
    }

    override func tableView(tableView: UITableView, canMoveRowAtIndexPath indexPath: NSIndexPath) -> Bool {
        return true
    }

    override func tableView(tableView: UITableView, editingStyleForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCellEditingStyle {
        return .None
    }
}

thanks a lot

wonderful solution, very usefull ！it solves my fuzzy of ordering the realm objects

Some Problem！，I have set
class MyObject: Object {
dynamic var order = 0
}
usage：
let results = try! Realm().objects(MyObject.self).sorted(byKeyPath: "order")

but when it goes to delete cell, its funny， whenever which cell I delete, the animation always delete the last one

finally I found that ,after any deletion, the rows will go to mass, I guess my order init is not correct, how about your order init?

And for initialization, I have capsuled a save method to set order, by the way

func save()  {

let realm = try! Realm()
realm.beginWrite()
self.order = APRealm().objects(self.classForCoder as! Object.Type).count
realm.add(self)
try! realm.commitWrite()

}

thanks very much

Swift 4.1:

`override func tableView(_ tableView: UITableView, moveRowAt sourceIndexPath: IndexPath, to destinationIndexPath: IndexPath) {
try! realm?.write {
let sourceObject = items[sourceIndexPath.row]
let destinationObject = items[destinationIndexPath.row]

        let destinationObjectOrder = destinationObject.order
        
        if sourceIndexPath.row < destinationIndexPath.row {
            
            for index in sourceIndexPath.row...destinationIndexPath.row {
                let object = items[index]
                object.order -= 1
            }
        } else {
            
            for index in (destinationIndexPath.row..<sourceIndexPath.row).reversed() {
                let object = items[index]
                object.order += 1
            }
        }
        sourceObject.order = destinationObjectOrder
    }
}`

Thank you
really helpful

Thank you. Solved a problem in my code.

Thanks Alot!!!

Thank you. Helped a lot

THANK YOU!!

Thank you 🎉

This is genius, thank you!