I wish to save a simple username via:
NSUserDefaults.standardUserDefaults().setObject("UncleRic", forKey:"username")
But when I return, particularly via re-activation of the app, I get nothing:
(lldb) po gUserDefault.objectForKey("username") as? String
nil
Here's the simple code:
import UIKit
let gUserDefault = NSUserDefaults.standardUserDefaults()
let userName = gUserDefault.objectForKey("username") as? String
let password = gUserDefault.objectForKey("password") as? String
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
NSUserDefaults.standardUserDefaults().setObject("UncleRic", forKey:"username")
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
I want to be able to access the User Default's values from the AppDelegate as well as from a UIViewcontroller.
How can I make this thing persistent?
Change your code to gUserDefault.setObject... and when you're done saving, call gUserDefault.synchronize()
Related
I'm trying to save a bool value to UserDefaults from a UISwitch, and retrieve it in another view. However, I've tried following multiple tutorials and stack answers and none seem to work.
This is how I'm saving it:
class SettingsViewController: UITableViewController {
#IBOutlet weak var soundSwitchOutlet: UISwitch!
#IBAction func soundSwitch(_ sender: UISwitch) {
UserDefaults.standard.set(soundSwitchOutlet.isOn, forKey: "sound")
}
and this is how I'm trying to retrieve it in another view:
if let savedValue = UserDefaults.standard.bool(forKey: "sound") {
boolValue = savedValue
}
//this is inside viewDidLoad and "boolValue" was declared outside viewDidLoad//
For a reason this code is giving me errors and none of the things I've tried have worked. How can I save a bool to UserDefaults and retrieve it in another view?
Edit: I think I fixed the first part. However, the way I'm retrieving the boolean seems to be totally wrong. Also: No other stackExchange answer responds to what I'm asking, at least not in swift.
As Leo mentioned in the comments bool(forKey returns a non-optional Bool. If the key does not exist false is returned.
So it's simply
boolValue = UserDefaults.standard.bool(forKey: "sound")
Calling synchronize() as suggested in other answers is not needed. The framework updates the user defaults database periodically.
Do it like this.
In your first view controller.
create an IBoutlet connection to your UISwitch
And then the action for your UISwitch. so in the end, your first view controller should look like this.
import UIKit
class FirstViewController: UIViewController {
#IBOutlet weak var myswitch: UISwitch! // Outlet connection to your UISwitch (just control+ drag it to your controller)
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func myswitchAction(_ sender: Any) { // Action for your UISwitch
var myswitctBool : Bool = false // create a local variable that holds your bool value. assume that in the beginning your switch is offed and the boolean value is `false`
if myswitch.isOn == true { // when user turn it on then set the value to `true`
myswitctBool = true
}
else { // else set the value to false
myswitctBool = false
}
// finally set the value to user default like this
UserDefaults.standard.set(myswitctBool, forKey: "mySwitch")
//UserDefaults.standard.synchronize() - this is not necessary with iOS 8 and later.
}
}
End of the first view controller
Now in your second view controller
you can get the value of userdefault, which you set in first view controller. I put it in the viewdidload method to show you how it works.
import UIKit
class SecondViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let myswitchBoolValuefromFirstVc : Bool = UserDefaults.standard.bool(forKey: "mySwitch")// this is how you retrieve the bool value
// to see the value, just print those with conditions. you can use those for your things.
if myswitchBoolValuefromFirstVc == true {
print("true")
}
else {
print("false")
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
Hope this will help to you. good luck
Use this line of code:
#IBAction func soundSwitch(_ sender: UISwitch) {
UserDefaults.standard.set(soundSwitchOutlet.isOn, forKey: "sound")
}
insteadof :
#IBAction func soundSwitch(_ sender: UISwitch) {
UserDefaults.standard.set(soundSwitchOutlet, forKey: "sound")
}
Try this:
#IBAction func soundSwitchs(_ sender: Any)
{
UserDefaults.standard.set(soundSwitchOutlet.isOn, forKey: "sound")
UserDefaults.standard.synchronize()
}
//this is inside viewDidLoad and "boolValue" was declared outside viewDidLoad//
boolValue = UserDefaults.standard.bool(forKey: "sound")
I'm following the instructions as shown in firebase but I'm still getting crashes even after making sure that the text entry is type String.
Here's the error:
Terminating app due to uncaught exception 'InvalidPathValidation', reason: '(child:) Must be a non-empty string and not contain '.' '#' '$' '[' or ']''
and here's the code:
import UIKit
import Firebase
import FirebaseDatabase
import FirebaseAuth
class BioEditViewController: UIViewController {
#IBOutlet weak var bioTextView: UITextView!
let databaseRef = FIRDatabase.database().reference()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func viewWillAppear(animated: Bool) {
let userID = FIRAuth.auth()?.currentUser?.uid
databaseRef.child("users").child(userID!).observeSingleEventOfType(.Value, withBlock: { (snapshot) in
// Get user level
let userBio = snapshot.value!["userBio"] as! String
self.bioTextView.text = userBio
})
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func doneSave(sender: UIButton) {
let textView = bioTextView.text
self.dismissViewControllerAnimated(false, completion: nil)
databaseRef.child("users/(user.uid)/userBio").setValue(textView)
}
}
I'm just trying to update a specific child: userBio and not affect the entire object.
Warning
Avoid instantiating your database reference to a variable out of scope. Reason why :- Outside your scope, when you instantiate a class to a variable you don't know wether or not your FIRApp has already been configured or not, or in general if that class has even been initialised as of yet or not. Just provide a reference(!) to the variable and instantiate later in a scope.
Change:-
let databaseRef = FIRDatabase.database().reference()
to
let databaseRef = FIRDatabaseReference!
And before using it just initialise it as:-
databaseRef = FIRDatabase.database().reference()
Try :-
#IBAction func doneSave(sender: UIButton) {
let textView = bioTextView.text
self.dismissViewControllerAnimated(false, completion: nil)
databaseRef = FIRDatabase.database().reference()
databaseRef.child("users/\(FIRAuth.auth!.currentUser!.uid)/userBio").setValue(textView)
}
Recently I have been making a app where you can create and quiz yourself on definitions or anything for that matter. I pass data to the next view after it the user hits the create button to make the title of the new notecard. The code I am using right now for that is:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let DestViewController: Card1 = segue.destinationViewController as! Card1
DestViewController.Content = Notetitle.text!
self.saved = self.Notetitle.text!
}
All of that works but, it will only work if I have a segue between viewcontrollers. I need to be able to pass that data with out a segue because I want the user to be able to create as many notecards as they want and the way I am trying to do that now is by using this code to make a copy of the UIView and then put in the new data (a master view). The new view can only be create using an IBAction. The prepare for segue I cannot use in the IBAction because it is it's own override function.
This is the code I am using to make a the new view:
let newCard =
self.storyboard!.instantiateViewControllerWithIdentifier("Main")
self.presentViewController(newCard, animated: true, completion:nil)
My hope is that I will be able to make a new view and then pass in the data pass in the data that the user just made to go on the notecard. (Hope this makes any sense at all)
MAIN TOPICS: -Create a new view and pass in new data Problem: Can pass data without a segue dont have one :/ -Be able to pass data between view controllers without a segue :)
I am new to all of this about 5 months. All of my code is in swift. Take it easy on me please. Feel free to ask me with any questions or comments. I have already posted a question on this but I didnt get an answer so have at it.
Thanks, Lucas Mazza
Don't use global variables unless you really need to. Making global static singleton's does not follow best practices. For more information read: What is so bad about singletons?
A better solution
You can use the protocol delegate pattern. I've actually written an article on this topic here:
https://www.codebeaulieu.com/36/Passing-data-with-the-protocol-delegate-pattern
You'll need a protocol that defines a function that will accept data. Then your other view controller will need to implement the delegate. If you need step-by-step details see the link provided above, alternatively you can simply download the project below and examine the code.
Download Working Example Project
Here's the code to make your protocol-delegate pattern work:
View Controller 1:
class ViewController: UIViewController, PresentedViewControllerDelegate {
#IBOutlet weak var textOutlet: UILabel!
#IBAction func doPresent(sender: AnyObject) {
let pvc = storyboard?.instantiateViewControllerWithIdentifier("PresentedViewController") as! PresentedViewController
pvc.data = "important data sent via delegate!"
pvc.delegate = self
self.presentViewController(pvc, animated: true, completion: nil)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func acceptData(data: AnyObject!) {
self.textOutlet.text = "\(data!)"
}
}
View Controller 2:
import UIKit
// place the protocol in the view controller that is being presented
protocol PresentedViewControllerDelegate {
func acceptData(data: AnyObject!)
}
class PresentedViewController: UIViewController {
// create a variable that will recieve / send messages
// between the view controllers.
var delegate : PresentedViewControllerDelegate?
// another data outlet
var data : AnyObject?
#IBOutlet weak var textFieldOutlet: UITextField!
#IBAction func doDismiss(sender: AnyObject) {
if textFieldOutlet.text != "" {
self.presentingViewController!.dismissViewControllerAnimated(true, completion: nil)
}
}
override func viewDidLoad() {
super.viewDidLoad()
print("\(data!)")
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
if self.isBeingDismissed() {
self.delegate?.acceptData(textFieldOutlet.text)
}
}
}
My question is about the UISlider. I managed to implement everything but i don't know how i can save its status.
Ive looked everywhere but al the posts are in older versions of swift/xcode. So the question is how do i save its status so that when i go to another view and then come back the status is still the same.
Thanks very much!
import UIKit
class SettingsViewController: UIViewController {
var sequeInt = 0
let savedWordLength = NSUserDefaults.standardUserDefaults()
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBOutlet weak var wordLength: UISlider!
#IBOutlet weak var wordLengthValue: UILabel!
var selectedValue: Int = 5
#IBAction func valueChanged(sender: UISlider) {
selectedValue = Int(sender.value)
savedWordLength.setInteger(selectedValue, forKey: "myInt")
let ourInt = savedWordLength.integerForKey("myInt")
sequeInt = ourInt
print (sequeInt)
wordLengthValue.text = String(ourInt)
}
UISlider value property is a Float so you can use NSUserDefault's method setFloat to save its value and retrieve it next time your view appears using NSUserDefaults method floatForKey.
to save it:
NSUserDefaults.standardUserDefaults().setFloat(sender.value, forKey: "wordLength")
load it:
override func viewWillAppear(animated: Bool) {
wordLength.setValue(NSUserDefaults.standardUserDefaults().floatForKey("wordLength"), animated: false)
}
Follow these steps.
In your view will appear.
fontSlider.setValue(UserDefaults.standard.float(forKey: "slider_value"), animated: false)
Take another outlet from storyBoard as "editingDidEnd".
In that function:
UserDefaults.standard.set(fontSlider.value, forKey: "slider_value")
And finally in your ValueChanged Outlet.
UserDefaults.standard.set(fontSlider.value, forKey: "slider_value")
I have my code so it puts an annotation on the map each time the user clicks a button, but when the user closes out of the app, the annotation disappears. How do I make it so the annotations stays on the map even when the user closes the app? Below is my code:
import UIKit
import CoreLocation
import MapKit
class UpdateCar: UIViewController, CLLocationManagerDelegate {
#IBOutlet weak var mapView: MKMapView!
#IBOutlet weak var lblLocation: UILabel!
var locationManager = CLLocationManager()
var myPosition = CLLocationCoordinate2D()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
locationManager.delegate = self
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func locationManager(manager: CLLocationManager!, didUpdateToLocation newLocation: CLLocation!, fromLocation oldLocation: CLLocation!) {
println("Updating Car Location \(newLocation.coordinate.latitude) , \(newLocation.coordinate.longitude) ")
myPosition = newLocation.coordinate
locationManager.stopUpdatingLocation()
lblLocation.text = "\(newLocation.coordinate.latitude) , \(newLocation.coordinate.longitude)"
}
#IBAction func findUserLocationAndDropPin(sender: UIButton) {
var userLocationCoordinates = CLLocationCoordinate2DMake(locationManager.location.coordinate.latitude, locationManager.location.coordinate.longitude)
var pinForUserLocation = MKPointAnnotation()
pinForUserLocation.coordinate = userLocationCoordinates
mapView.addAnnotation(pinForUserLocation)
mapView.showAnnotations([pinForUserLocation], animated: true)
}
}
You have to save it in a persistent store.
Few options:
CoreData, the native way of saving data, recommended, not too easy
NSUserDefaults, usually thought for small stuff, also native, not recommended, very easy though
Another API for managing a persistent store like Realm (similar to CoreData, a little easier but not native)
//when I need to save for example, the last date on which the user login my app will use the setObject function, this will save a value ("10/05/2015") in the "lastlogin" key
var lastLogin = "10/05/2015"
NSUserDefaults.standarUserDefaults().setObject(lastLogin, forkey: "lastLogin")
//And when I need to retrieve the stored value in the "lastlogin" key which I use is "objectForKey" function
NSUserDefaults.standarUserDefaults().objectForKey("lastLogin")
see following link:
https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/index.html#//apple_ref/occ/instm/NSUserDefaults/setObject:forKey: