Hello I am currently doing a project where the user types something in a textfield, and presses a button, where whatever the user types in the textfield appears as part of the alertbody of a notification.
To do this I save the textfield.text as a variable and then use string interpolation to include it into the alertbody.
The problem is that the time in which I fire the notifications change every week, so I have to make new notifications. And I still want to use whatever the user typed into the textfield. But since the textfield.text was saved inside a function, I do not think that it will be stored outside the function.
This is what my code looks like so far
override func viewDidLoad() {
super.viewDidLoad()
timer = NSTimer.scheduledTimerWithTimeInterval(604800, target: self,selector:Selector("repeater"), userInfo: nil, repeats: true)
}
savedtext:String!
#IBAction func setNotification{
textfield.text = savedtext
//set notifications and other stuff here
}
//outside the function savedtext should not have the textfield's info
func repeater{
//setting notification
}
Sorry if my question is a bit difficult to understand
Any help is appreciated
I'd use NSUserDefaults here, it will persist your data in a key-value map, even after the user or system kills the app. The code would look like this
let ALERT_MESSAGE_KEY : String = "myAlertMsgKey"
#IBAction func setNotification{
let defaults = NSUserDefaults.standardUserDefaults()
defaults.setValue(textfield.text , forKey: ALERT_MESSAGE_KEY)
NSUserDefaults.standardUserDefaults().synchronize()
//set notifications and other stuff here
}
and in repeater function:
func repeater {
let defaults = NSUserDefaults.standardUserDefaults()
let alertMessage = defaults.valueForKey(ALERT_MESSAGE_KEY) as? String ?? "No message saved"
}
You could also use Core Data for this, but it would be an overkill for something so simple
Related
I've been looking for a way to trigger a method when the number of displays connected to a mac changes. I know I can get the value of NSScreen.screens.count, but I need to find a way to create a notification or something when that value changes or something else that would indicate a change in the number of displays connected.
I have tried KVO examples here and here, but in order for either of those to work there needs to be an event that triggers the methods inside the class.
In essence this is what I would like to do based on the first link:
class EventObserverDemo {
var statusObserver: NSKeyValueObservation?
var objectToObserve: NSScreen.screens.count?
func registerAddObserver() -> Void {
statusObserver = objectToObserve?.observe(NSScreen.screens.count, options: [.new, .old], changeHandler: {[weak self] (NSScreen.screens.count, change) in
if let value = change.newValue {
// observed changed value and do the task here on change.
print("The display count has changed.")
}
})
}
func unregisterObserver() -> Void {
if let sObserver = statusObserver {
sObserver.invalidate()
statusObserver = nil
}
}
}
I tried using a notification that used NSScreen.colorSpaceDidChangeNotification but that does not trigger a notification if a display is disconnected.
I would like to find a way to detect any time an external display is connected or disconnected. There has to be something I haven't found yet because whenever I plug in an external display to my mac I see the screen on the main display change, so there's some kind of notification that something changed whether I plug in a display or unplug it from my mac.
I looked at the didSet function, but I couldn't figure out a way to implement that on NSScreen.screens.count property.
I also looked into a property wrapper for NSScreen.screens.count but again I couldn't figure that out either.
You can observe the NSApplication.didChangeScreenParametersNotification notification. This example will only print once each time a display is either connected or disconnected, and what the change was in the number of screens.
Code:
class EventObserverDemo {
var lastCount = NSScreen.screens.count
init() {
NotificationCenter.default.addObserver(
self,
selector: #selector(trigger),
name: NSApplication.didChangeScreenParametersNotification,
object: nil
)
}
#objc private func trigger(notification: NSNotification) {
let newCount = NSScreen.screens.count
if newCount != lastCount {
print("Switched from \(lastCount) to \(newCount) displays")
lastCount = newCount
}
}
}
You don't need to remove/invalidate the observer either, easier to let the system handle it:
If your app targets iOS 9.0 and later or macOS 10.11 and later, you do not need to unregister an observer that you created with this function. If you forget or are unable to remove an observer, the system cleans up the next time it would have posted to it.
I am new to macOS Development and I am working on a project for macOS using Xcode 10 and Swift 4.2.
The project contains mainly 3 view controllers.
Firstly, ViewController (the main welcome screen which separates the other two) has two buttons to call the other two respectively.
Secondly, MakeEntry View Controller creates an array of strings data variable using a form type structure comprised of text views and save button etc. which in the end just saves all input data into an array of strings data variable called carrierArray
Thirdly, there is a split view controller for displaying two children view controller namely EntryList and EntryDetail
EntryList (the left pane) contains a Table View to display titles of entries and EntryDetail (the right pane) will contain the description of the title entry (somewhat like the default notes app of macOS)
I want to achieve a simple functionality of being able to access or read that Array of strings variable called carrierArray which is created when the MakeEntry view controller saves it into a global variable defined within its own class file But I want to access that array of strings anywhere and anytime later.
I cannot use delegates and protocols, closures, segues or storyboard identifiers to carry that data because I am not navigating to the Split View Controller straightaway and also because I want to store that data
to manipulate it further before displaying it in the right pane of split view controller (EntryDetail) .
I am unable to figure out whether how it might be possible to achieve this functionality using NSUserDefaults or CoreData.
Therefore I tried using the Notification Centre after storing that array of Strings in a Dictionary namely notifDictionary containing a key called carryData to be stored as the data object of notification centre And with some research and some trials and errors but without any luck all resulting in failure to get that data in the split view controller left pane class file namely (EntryDetail).
Code Snippets are as below, thanks a lot in advance for the kind help.
In MakeEntry View controller:
notifDictionary = ["carryData": carrierArray]
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "dataCarrier") , object: nil, userInfo: notifDictionary)
In EntryList View Controller:
(Tried using both types of selector methods one at a time and even using them together but all without luck! Please Help!)
The Variable datumDict and datumArray and nothing but copy receivers for carrierArray and notifDictionary
var datumDict: [String:[String]] = [:]
var datumArray: [String] = []
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(self.getThatDict(_:)), name: NSNotification.Name(rawValue: "dataCarrier") , object: nil)
NotificationCenter.default.addObserver(forName: NSNotification.Name(rawValue: "dataCarrier") , object: nil, queue: nil, using: catchNotification)
//datumArray = datumDict["carryData"]!
}
#objc func onNotification(notification:Notification)
{
print(notification.userInfo!)
}
func catchNotification(notification: Notification) -> Void
{
let theDict = notification.object as! NSDictionary
datumDict = theDict as! [String: [String]]
guard let theData = notification.userInfo!["carryData"] as? [String:[String]] else { return }
datumDict = theData
}
#objc func getThatDict(_ notification: NSNotification)
{
print(notification.userInfo ?? "")
if let dict = notification.userInfo as NSDictionary?
{
if let thatDict = dict["carryData"] as? [String: [String]]
{
datumDict = thatDict
}
}
}
With the caveat that "globals and singletons should be avoided," it sounds like they are a good fit for what you're trying to do. As you get more comfortable in Cocoa you can move into more sophisticated means of accomplishing this (dependency injection). Look into this as you get more comfortable with Cocoa.
Create a simple singleton type:
// AppState.swift
class AppState {
// Basic singleton setup:
static let shared = AppState()
private init() {} // private prevents instantiating it elsewhere
// Shared state:
var carrierArray: [String] = []
}
Access it from your view controllers:
// YourViewController.swift:
#IBAction func doSomething(_ sender: Any) {
AppState.shared.carrierArray = ...
}
If you need to update the other view controllers when this shared state changes, notifications are a good tool for that. You could do this with a didSet on carrierArray, or simply trigger the notification manually.
(looking for the best approach to save Realm property.
I have a UIViewController with a lot of TextView, etc that I fill from a Realm object.
Each time the textfield are modified, I need to send back to change un the realm property.
The (not cool) thing, are that I cannot save directly, I have to open a write transaction.
object.propertyA= “hello” // crash
try! realm.write { //work
userBeer?.Name = lblbeerName.text!
}
So, i found a bit painfull (and not clean) to to that for all text.
I’ve looked at rxRealm, but cannot see any (newbies) sample to make that.
So, I have 2 approach un mind
Modify the model getters and setters for the property
var beerName: String? {
get {
return self.Name
}
set {
try! realm.write {
self.txtName=beerName!
}
}
use the RXSwift approach from here (https://www.raywenderlich.com/149753/bond-tutorial-bindings-swift)
Bing the TextField.text to a var String, and observe this string to write.
What do you think?
My perfect world will be to find a way to bing the TextField.text property directly, something like:
myRealmObject.property.BindTo(self.txtName)
Katsumi from Realm here. Although it is not the best approach, I propose another way. You can use realm.beginWrite() and try! realm.commitWrite() instead of block-based API for a long-lived transaction.
For example, you can open a transaction when the view appeared, and then close the transaction when the view disappeared, like the following:
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
realm.beginWrite()
}
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
try! realm.commitWrite()
}
In this way, you can assign a value to the Realm object at any time in the view.
Be careful not to leave the transaction open. To avoid increasing file size, do not update data frequently in the background while transactions are open.
Change the property within the write block:
try! realm.write {
object.propertyA = “hello”
userBeer?.Name = lblbeerName.text!
}
On Watch, I'm able to pass a saved workout from the WorkoutInterfaceController to the SummaryInterfaceController. But I was wondering how to pass the saved workout from the Watch to the iPhone (so I can display it in a Summary View Controller too).
Do you know? Or is there a better way I'm supposed to do this?
Here's what I use to pass the saved workout from WorkoutInterfaceController to the SummaryInterfaceController:
private func saveWorkout() {
// Create and save a workout sample
let configuration = workoutSession!.workoutConfiguration
let isIndoor = (configuration.locationType == .indoor) as NSNumber
print("locationType: \(configuration)")
let workout = HKWorkout(activityType: configuration.activityType,
start: workoutStartDate!,
end: workoutEndDate!,
workoutEvents: workoutEvents,
totalEnergyBurned: totalEnergyBurned,
totalDistance: totalDistance,
metadata: [HKMetadataKeyIndoorWorkout:isIndoor]);
healthStore.save(workout) { success, _ in
if success {
self.addSamples(toWorkout: workout)
}
}
WKInterfaceController.reloadRootControllers(withNames: ["SummaryInterfaceController"], contexts: [workout])
}
private func addSamples(toWorkout workout: HKWorkout) {
// Create energy and distance samples
let totalEnergyBurnedSample = HKQuantitySample(type: HKQuantityType.activeEnergyBurned(),
quantity: totalEnergyBurned,
start: workoutStartDate!,
end: workoutEndDate!)
// Add samples to workout
healthStore.add([totalEnergyBurnedSample], to: workout) { (success: Bool, error: Error?) in
if success {
// Samples have been added
}
}
}
Let me know if any questions or information needed, thanks!
As a part of my research and development,I discovered how the pairing of the iPhone and the Apple Watch has the potential to be useful.
In this case, tapping on a button on the Watch app will send text on the iPhone.
To make a simple demo of this functionality, place a button on the WatchKit interface and a label on the iOS app’s storyboard.
Now, hook up the button to the WatchKit Interface Controller as an IBAction in order to respond to button tap events. Also hook up the Label to the UI View Controller as an IBOutlet.
In the Interface Controller, we make up a string variable to send to the label and in the button’s IBAction method, make a dictionary that includes the string variable you made. This dictionary is what is passed to the iPhone app.
class InterfaceController: WKInterfaceController {
Var str: String = "Hello Phone"
#IBAction func button() {
let dict: Dictionary = ["message": str]
}
Use the following method to send the dictionary to the iPhone.
WKInterfaceController.openParentApplication(dict, reply: {(reply, error) -> void in
print("Reply receive from iPhone app")
})
In the AppDelegate of the iOS app, add the following application method. This is what will handle the previous methods communication from the Watch. Also we can use a notification to notify a view controller that data has been received and to pass it along.
func application(application: UIApplication, handleWatchkitExtensionRequest userInfo: [NSObject : AnyObject]?, reply:(([NSObject : AnyObject]!) {
NSNotificationCenter.defaultCenter().postNotificationName("WatchKitReq", object: userInfo)
}
Finally in the view controller, make a listener for the notification that will update the label’s text to the string that was sent with the data.
class ViewController: UIViewController {
#IBOutlet weak var label: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector("handleWatchKitNotification:"), name: "WatchKitReq", object: nil)
}
func handleWatchKitNotification(notification: NSNotification) {
if let userInfo = notification.object as? [String : String] {
label.text = userInfo["message"]
}
}
Hope this will help you to understand. For more concerns you can look on this,
Delegate Method
To do this you have to create an App Group which is essentially a space which both apps can use. It was brought in with the exetension framework in iOS8 so apps can communicate with their Today widgets, or custom keyboards, and amongst other applications.
ADD CAPABILITIES
The first thing we have to do is add the app group capability to both our iPhone and Watch Watch Extension targets.
To do this open up the project settings (blue icon at the top of the list of files) and select the iPhone target. You will need to select the “capabilities” tab at the top of the page and scroll down to turn on app groups.
This requires a connected developer profile, and will take a while to enable. You’ll need to do the same steps to switch on app groups for the watch kit extension also.
Next you need to ensure that the app group string is an identifier string you want and that makes sense for your app, it must start with the word group or it complains. You can also add multiple groups if you wish. Whatever you pick they must be enabled with a blue tick (again this might take a while) and are exactly the same for both the iPhone and Watch extension targets!
To use App Groups, it’s not that different or difficult to use than NSUserDefaults:
var userDefaults = NSUserDefaults(suiteName: "group.com.example.My-App")
userDefaults.setObject(true, forKey: "isDarkModeEnabled")
userDefaults.synchronize()
The only differences here are how NSUserDefaults is instantiated and calling synchronize at the end. You feed it the container ID to the constructor parameter called “suiteName”, then call “synchronize()”, and your data flies to the cloud for other apps and devices to consume.
Taking It to the Next Level
You can take this one step further by creating a class for your app and abstract the underlying storage for your properties. Here’s an example:
public class ConfigurationModel: NSObject {
public static let storageKey = "group.com.example.My-App"
public let userStorage = NSUserDefaults(suiteName: storageKey)
public var isDarkModeEnabled: Bool {
get {
// Get setting from storage or default
if userStorage?.objectForKey("isDarkModeEnabled") == nil {
userStorage?.setObject(false, forKey: "isDarkModeEnabled")
userStorage?.synchronize()
}
return userStorage?.objectForKey("isDarkModeEnabled")
}
set {
// Set new value in storage
userStorage?.setObject(newValue, forKey: "isDarkModeEnabled")
userStorage?.synchronize()
}
}
At the top of the class, I am declaring my group container ID and creating the NSUserDefault object out of it. Then my properties for the class have getters and setters to store the data to the App Group. If the key doesn’t exist, it creates it with a default value and synchronizes it. Using the class from this point forward is simple:
var configModel = ConfigurationModel()
configModel.isDarkModeEnabled = true
This property is stored in the cloud! Everything is abstracted away for you. You don’t have to be bothered about storing and synchronizing it into the App Group. It’s all done automatically for you in the getters and setters!
Hope, this will help you to understand how you can share data between the iPhone and Apple Watch app.
I think it is something really easy but I am a noob and I can't figure out what to do, So I am trying to check if the TextField has nothing inside it, it would let the user write something in it, but if it has some text saved (I have saved the data using NSUserDefaults) in there when you quit the app it will remain the text that was typed in that TextField.
I had accomplished this before but something went wrong and stopped working.
Here is what I have done:
var notTheFirstTime = false
if notTheFirstTime == true{
let mail = NSUserDefaults.standardUserDefaults().objectForKey("usersMailID") as! String
textField.text = "\(mail)"
}
Here is the part where the text filed is saved and change the status of the "notTheFirstTime" to true
func textFieldShouldReturn(textField: UITextField) -> Bool {
performAction()
return true
}
func performAction() {
notTheFirstTime = false
NSUserDefaults.standardUserDefaults().setObject(textField.text!, forKey: "usersMailID")
NSUserDefaults.standardUserDefaults().synchronize()
print("Saved!!!!!!")
saveLabel.text! = "Saved!"
savedIcon.image = UIImage(named: "Saved")
}
I see two things in this code, After the text saved in to user default you should use
notTheFirstTime = true
but you set this as false in performAction()
Second one is you should use notTheFirstTime value also as a User defaults. When you close the app. This value also rest to the false( as you given on initial step of the application) So use it's value also as a user defaults.