Store data in plist with NSFileManager

This example is written in Swift 2.2 with Xcode 7.3.1.

For an iOS app, permanent data may be stored in CoreData, in a simple text file, or in a plist file. This example stores information in a plist file. The steps

1. Add a new property list file:

2. Edit the key, type and value of the plist as below:

3. Modify ViewController.swift as below:

import UIKit

class ViewController: UIViewController {

    var num   : Int = 0

    var label : UILabel!

    

    let path = NSHomeDirectory()+"/Documents/Storage.plist"

    var dictionary : NSMutableDictionary!

    let fileManager = NSFileManager.defaultManager()

    

    override func viewDidLoad() {

        

        super.viewDidLoad()

        

        checkFile()

        

        dictionary = NSMutableDictionary(contentsOfFile: path)

        

        let button = UIButton(frame: CGRectMake(0,0,100,30))

        button.center = view.center

        button.setTitle("Generate", forState: UIControlState.Normal)

        button.addTarget(self, action: #selector(btnGenerate), forControlEvents: UIControlEvents.TouchUpInside)

        button.setTitleColor(UIColor.blueColor(), forState: UIControlState.Normal)

        button.setTitleColor(UIColor.cyanColor(), forState: UIControlState.Highlighted)

        view.addSubview(button)

        

        label = UILabel(frame: CGRectMake(0,0,100,30))

        label.center = CGPointMake(view.center.x, view.center.y-50)

        label.textAlignment = NSTextAlignment.Center

        label.text = "\(num)"

        view.addSubview(label)

        

        read()

        

        let buttonDel = UIButton(frame: CGRectMake(0,0,100,30))

        buttonDel.center = CGPointMake(view.center.x, view.center.y+50)

        buttonDel.setTitle("Delete plist", forState: UIControlState.Normal)

        buttonDel.addTarget(self, action: #selector(btnDel), forControlEvents: UIControlEvents.TouchUpInside)

        buttonDel.setTitleColor(UIColor.blueColor(), forState: UIControlState.Normal)

        buttonDel.setTitleColor(UIColor.cyanColor(), forState: UIControlState.Highlighted)

        view.addSubview(buttonDel)

    }

    

    func btnGenerate() {

        num = Int(arc4random()%100)

        label.text = "\(num)"

        write()

        

        dictionary = NSMutableDictionary(contentsOfFile: path)

    }

    

    func btnDel() {

        print("btnDel")

        label.text = "0"

        do {

            try fileManager.removeItemAtPath(path)

        } catch {

            print("Unable to delete the plist file")

        }

    }

    

    func checkFile() {

        

        if !fileManager.fileExistsAtPath(path) {

            print("File not exist!")

            

            let srcPath = NSBundle.mainBundle().pathForResource("Storage", ofType: "plist")

            

            do {

                //Copy the project plist file to the documents directory.

                try fileManager.copyItemAtPath(srcPath!, toPath: path)

            } catch {

                print("File copy error!")

            }

        }

    }

    

    func read() {

        label.text = "\(dictionary!.objectForKey("Num")!)"

        print(dictionary!.objectForKey("Num")!)

    }

    

    func write() {

        dictionary.setValue(num, forKey: "Num")

        dictionary.writeToFile(path, atomically: true)

        print("write")

    }

    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

    }

}

Related Information:

NSSearchPathForDirectoriesInDomains - Read/Write a file in an iOS app