Adding things to NSUserDefaults - multiple views - ios

Question

I am creating a dictionary-like app and I want to store the user's search history using NSUserDefaults. I created a seaechHistory array outside the class. Now I am appending the searchHistory array and save it using NSUserDefaults in willSelectRowAtIndexPath, and I retrieve the stored history in a history view. The storage worked fine but when I re-run the app the NSUserDefaults set the seachHistory to the empty array and thus I lost all the saved data. The synchronize() method does work anywhere.
Initial View Controller:
import UIKit
var searchHistory = [String]()
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, UITextFieldDelegate {
#IBOutlet weak var tableView: UITableView!
#IBOutlet var textField: UITextField!
#IBAction func textFieldDidChange(sender: AnyObject) {
tableView.hidden = false
searchManager.updateFilter(textField.text)
tableView.reloadData()
}
#IBAction func tapOnTextField(sender: AnyObject) {
let textFieldLength = count(textField.text)
if textFieldLength == 0 {
tableView.hidden = true
} else {
tableView.hidden = false
}
}
override func viewDidLoad() {
super.viewDidLoad()
textField.backgroundColor = UIColor.whiteColor()
tableView.hidden = true
self.textField.delegate = self
}
var searchManager = SearchManager()
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return searchManager.filteredURLCount()
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: UITableViewCellStyle.Default, reuseIdentifier: "Cell")
cell.textLabel!.text = searchManager.filteredURLAtIndex(indexPath.row)
return cell
}
func tableView(tableView: UITableView, willSelectRowAtIndexPath indexPath: NSIndexPath) -> NSIndexPath? {
self.textField.text = searchManager.filteredURLAtIndex(indexPath.row)
searchHistory.append(textField.text)
NSUserDefaults.standardUserDefaults().setObject(searchHistory, forKey: "History")
self.performSegueWithIdentifier("cellTapped", sender: "Cell")
textField.text = nil
tableView.hidden = true
textField.resignFirstResponder()
return indexPath
}
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
self.view.endEditing(true)
self.tableView.hidden = true
}
func textFieldShouldReturn(textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "cellTapped" {
var DestViewController: definitionView = segue.destinationViewController as! definitionView
DestViewController.searchWord = textField.text
}
}
}
History View Controller:
import UIKit
class historyView: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
searchHistory = NSUserDefaults.standardUserDefaults().objectForKey("History")! as! [String]
println(searchHistory)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
var destination: ViewController = segue.destinationViewController as! ViewController
}
}

Answer 1

You can read your array in viewDidLoad() method, then it won't be empty.
Add tihs code in your ViewController:
override func viewDidLoad() {
super.viewDidLoad()
searchHistory = NSUserDefaults.standardUserDefaults().objectForKey("History")! as! [String]
}
It should work.