i have the following code which print the url of updated image
override func viewWillAppear(animated: Bool) {
NSNotificationCenter.defaultCenter().addObserver(self, selector: "assetChange:", name: ALAssetsLibraryChangedNotification, object: nil) }
func assetChange(notification: NSNotification){
if var info:NSDictionary = notification.userInfo { var url:NSSet = info.objectForKey(ALAssetLibraryUpdatedAssetsKey) as NSSet
var aurl:NSURL = url.anyObject() as NSURL
println(aurl)
}
}
this code work fine but it will print only first modified image url,but i want all the list of modified image url(array of modified images) please help me
You're choosing one object from the set when using url.anyObject(). Instead you need to get all objects from the set and then iterate through the array. The following code should help you:
func assetChange(notification: NSNotification) {
if var info:NSDictionary = notification.userInfo { var url:NSSet = info.objectForKey(ALAssetLibraryUpdatedAssetsKey) as NSSet
var urls: [NSURL] = url.allObjects as [NSURL]
for singleUrl in urls {
println(singleUrl)
}
}
}
Related
I've been trying to figure out how Core Data works with using Swift. I don't think I'm grasping the proper concept of the whole thing. I get that I need to be interacting with Context to store data to PersistentContainer, but it seems everytime I press on save button, the data is stored as brand new. I want it to be able to update the existing row. Below is my code. Any help will be greatly appreciated. Thank you.
import UIKit
import CoreData
class ViewController: UIViewController {
var editNotes: Note?
let dataFilePath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
#IBOutlet weak var textView: UITextView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
#IBAction func saveButton(_ sender: UIButton) {
print (dataFilePath)
print (sender.tag)
var new: Note?
if let note = editNotes {
new = note
} else {
new = Note(context: context)
}
new?.body = textView.text
new?.date = NSDate() as Date
do {
ad.saveContext()
self.dismiss(animated: true, completion: nil)
} catch {
print(“cannot save”)
}
}
}
I want to save the user's filter selections on FilterViewController.
When FilterViewController is closed, NSKeyedArchiver.archiveRootObject archives the user's selections. However, NSKeyedUnarchiver.unarchiveObject opens up the initial default selections (NOT the user's selections). How to fix this?
FiltersViewController.swift
override func viewWillAppear(_ animated: Bool) {
if let filterSections = NSKeyedUnarchiver.unarchiveObject(withFile: filterViewModel.filtersFilePath) as? [FilterSection] {
// Retrieves initial default selections, NOT user's selection
filterViewModel.filterSections = filterSections
filtersTableView.reloadData()
}
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
// Saves what user selects
let isSuccessful = NSKeyedArchiver.archiveRootObject(self.filterViewModel.filterSections, toFile: self.filterViewModel.filtersFilePath)
if (isSuccessful) {
print("Saved filters") // This is printed
} else {
print("Didn't Save filters")
}
}
FilterViewModel.swift
class FilterViewModel: NSObject {
// Contains all filtered sections displayed on table view
var filterSections: [FilterSection] = []
// File Path to saved Filter Sections
var filtersFilePath: String {
let manager = FileManager.default
let url = manager.urls(for: .documentDirectory, in: .userDomainMask).first
print("this is the url path in the documentDirectory \(url)")
return (url!.appendingPathComponent("FilterSelectionData").path)
}
override init() {
super.init()
filterSections = self.getFilterSections()
}
}
CompanyViewController.swift
#objc func filterButtonTapped() {
var filterViewModel: FilterViewModel
if (self.filterViewModel != nil) {
filterViewModel = self.filterViewModel! // This runs
}
else {
self.filterViewModel = FilterViewModel()
filterViewModel = self.filterViewModel!
}
let filtersVC = FiltersViewController(filterViewModel: filterViewModel)
self.navigationController?.pushViewController(filtersVC, animated: true)
}
You are using self.getFilterSections to set filterSections in FilterViewModel init. I suppose self.getFilterSections is a method that returns the default values. For me, it should not be the case, rather if you have archived some values, you should get that in this method. Although, this alone should not be the reason for the issue, but may be a reason for inducing bug. Try changing self.getFilterSections to return archived values if possible otherwise default values and check whether the bug is still there.
With removeObserver(withHandle in Swift 3, the Observer is not removed on viewDidDisappear
var query = FIRDatabaseQuery()
var postRef: FIRDatabaseReference!
var postRefHandle: FIRDatabaseHandle?
override func viewDidLoad() {
super.viewDidLoad()
postRef = baseRef.child("Posts")
}
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
if postRefHandle != nil {
//try 1:
//postRef.removeObserver(withHandle: postRefHandle!)
//try 2:
//postRef.queryOrdered(byChild: "sortTimestamp").removeObserver(withHandle: postRefHandle!)
//try 3:
//query.removeObserver(withHandle: postRefHandle!)
}
//try 4:
//postRef.removeAllObservers() //works
}
func getPosts()
{
var count = 20
query = postRef.queryOrdered(byChild: "sortTimestamp")
postRefHandle = query.queryLimited(toFirst: UInt(count)).observe(.childAdded //etc.
}
So I tried the three methods in viewDidDisappear, but the observer is not removed.
try 3 query.removeObserver(withHandle: postRefHandle!) as by answer from Firebase, how do I return a handle so that I can call removeObserver? by frank-van-puffelen
The only one that does work is the one outlined in try 4.
Any reason why I cannot remove the Observer with removeObserver(withHandle? (try 1 - 3)
Also "query.queryLimited(toFirst: UInt(count)).observe(.childAdded" does not get the latest data from Firebase. I was under the impression the observe always gets the updated data, as opposed to observeSingleEvent. Why does it not do that?
Any suggestions are much appreciated.
If you have the following code:
var postsRef: FIRDatabaseReference!
var postRefHandle: FIRDatabaseHandle!
var query = FIRDatabaseQuery()
func addHandler() {
self.postsRef = self.ref.child("posts")
var count = 20
self.query = self.postsRef.queryOrdered(byChild: "sortTimestamp")
self.postRefHandle = self.query.queryLimited(toFirst: UInt(count)).observe(.childAdded, with: { snapshot in
print(snapshot)
})
}
and at a later time you do this function
self.postsRef.removeObserver(withHandle: self.postRefHandle!)
It removes the observer. This is tested code.
To the second part of your question: querySingleEvent and observe do the same thing data wise but have different behaviors. They will both always get current data - modified by startAt, endAt, equalTo etc.
observeSingleEvent returns the data, does NOT leave an observer so you
will not be notified if that data changes
observe returns the data and leaves an observer attached to the node
and will notify you of future changes.
.childAdded: when any children are added to the node
.childChanges: when any children change in the node
.childRemoved: when a child is removed.
How I'm Able to Achieve this is by removing child reference.
var recentRef: FIRDatabaseReference!
recentRef.child("\(groupId)").observe(.value, with: { (snapshot) in
recentRef.removeAllObservers() // not_working
recentRef.child("\(groupId)").removeAllObservers() //working
if let obj = snapshot.value as? [String: AnyObject] {
//... code here
}
})
You can achieve this without making a query also(Swift 4) -
This removes the reference of the observer properly and works for me.
private let ref = Database.database().reference().child("classTalks")
private var refHandle: DatabaseHandle!
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear()
refHandle = ref.observe(.value, with: { (snapshot) in
...
})
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear()
ref.removeObserver(withHandle: refHandle)
}
I am trying to do dynamic picker view which shows extra data whenever I will get new input in data base.
At this moment I am using notification and observer to take care of real time updates. Also I am removing all items from string array to get just one newest record - it is not what i want.
override func viewDidLoad() {
super.viewDidLoad()
pickerView.delegate = self
pickerView.dataSource = self
pickerView.sizeToFit()
NotificationCenter.default.addObserver(forName: SEARCH_RESULT, object: nil, queue: nil, using: catchNotificationForSearchResult)
}
func catchNotificationForSearchResult(_notification: Notification) {
let _resultSearch = _notification.object as! [Class]
for _result in _resultSearch {
_stringArray.removeAll()
_stringArray.append("AAA : \(_result.aaa), BBB \(_result.bbb), CCC : \(_result.ccc)")
pickerView.reloadAllComponents()
}
}
AppDelegate:
fun test() {
let _fetchRequest:NSFetchRequest<Class> = Class.fetchRequest()
do {
let _searchResults = try DataBaseController.getContext().fetch(_fetchRequest)
NotificationCenter.default.post(name: SEARCH_RESULT, object: _searchResults)
} catch {
print("Error \(error)")
}
}
Thanks in advance!
My Game Center Authentication is not working. When I build and run, it won't show my username.. has signed in. Also, when I try to add my score I get a screen that says "no data availible". Heres my code.
override func viewDidLoad() {
super.viewDidLoad()
gcAuthPlayer()
}
#IBAction func GCButton(sender: AnyObject) {
saveHighScore(GameScene().highScoreNumer)
showLeaderBoard()
if GameScene().currentScore > GameScene().highScoreNumer{
saveHighScore(GameScene().currentScore)
}
}
func showLeaderBoard(){
let viewController = self.view.window?.rootViewController
let gcvc = GKGameCenterViewController()
gcvc.gameCenterDelegate = self
viewController?.presentViewController(gcvc, animated: true, completion: nil)
}
func saveHighScore(number: Int){
if GKLocalPlayer.localPlayer().authenticated{
let scoreReporter = GKScore(leaderboardIdentifier: "myleaderboard")
scoreReporter.value = Int64(number)
let scoreArray : [GKScore] = [scoreReporter]
GKScore.reportScores(scoreArray, withCompletionHandler: nil)
}
}
func gcAuthPlayer(){
let localPlayer = GKLocalPlayer.localPlayer()
localPlayer.authenticateHandler = {
(view, error) in
if view != nil{
self.presentViewController(view!, animated: true, completion: nil)
}else{
print(GKLocalPlayer.localPlayer().authenticated)
}
}
}
func gameCenterViewControllerDidFinish(gameCenterViewController: GKGameCenterViewController) {
gameCenterViewController.dismissViewControllerAnimated(true, completion: nil)
}
This code makes no sense
saveHighScore(GameScene().highScoreNumer)
showLeaderBoard()
if GameScene().currentScore > GameScene().highScoreNumer{
saveHighScor
You are creating a new instance of GameScene everytime you try to update the score and therefore your score is nil
I would need to see some more code but for now you need to change the score property in your game scene. For example make it a static property so you can get it in other classes.
class GameScene: SKScene {
static var currentScore = 0
static var highscoreNumber = 0
}
Than in your Scenes or ViewController you can get it like so
GameScene.currentScore = 5
GameScene.highscoreNumber = 5
Just remember that you have to reset the score to 0 everytime you restart your gameScene because it a static property.
GameScene.currentScore = 0
GameScene.highscoreNumber = 0
Than your code to post the score should look like this
saveHighScore(GameScene.highScoreNumer)
showLeaderBoard()
if GameScene.currentScore > GameScene.highScoreNumer{
saveHighScor
Your score reporting code should also handle the error and actually do the completion handler. So change it to something like this.
/// Save leaderboard progress
func reportLeaderboardProgress(value: Int, leaderboardID: String) {
let scoreReporter = GKScore(leaderboardIdentifier: leaderboardID)
scoreReporter.value = Int64(value)
GKScore.reportScores([scoreReporter]) { error in // Trailing Closure syntax
if let error = error {
print(error.localizedDescription)
return
}
print("Reported leaderboard progress \(value) to leaderboardID \(leaderboardID)")
}
}
It is also a good idea to move that code into another class to keep your overall code cleaner and more reusable.
For a nice and simple example check this helper on gitHub.
https://github.com/jackcook/GCHelper
Let me know how it goes.