TableView not updating - xcode

I'm currently struggling with getting my TableView to update after I finish performing some functions called in viewDidLoad and viewDidAppear. I tried using self.tableView.reloadData() at the end of my viewDidLoad but it didn't work and upon reloading the tab, the app would crash.
Here is some of my code (I'm trying to fetch events from a Google Calendar and display it in a TableView). I'm trying to display an array of strings named listOfEvents and it is being populated after the tableView is already loaded.
I also tried adding self.tableView.reloadData() at the end of my fetchEvents() but it also killed my app upon reloading the tab
class CalendarViewController: UITableViewController {
var listOfEvents: [String] = []
private let kKeychainItemName = "Google Calendar API"
private let kClientID = "clientID"
// If modifying these scopes, delete your previously saved credentials by
// resetting the iOS simulator or uninstall the app.
private let scopes = [kGTLAuthScopeCalendarReadonly]
private let service = GTLServiceCalendar()
let output = UITextView()
// When the view loads, create necessary subviews
// and initialize the Google Calendar API service
override func viewDidLoad() {
super.viewDidLoad()
if let auth = GTMOAuth2ViewControllerTouch.authForGoogleFromKeychainForName(
kKeychainItemName,
clientID: kClientID,
clientSecret: nil) {
service.authorizer = auth
}
}
// When the view appears, ensure that the Google Calendar API service is authorized
// and perform API calls
override func viewDidAppear(animated: Bool) {
if let authorizer = service.authorizer,
canAuth = authorizer.canAuthorize where canAuth {
fetchEvents()
} else {
presentViewController(
createAuthController(),
animated: true,
completion: nil
)
}
}
// Construct a query and get a list of upcoming events from the user calendar
func fetchEvents() {
let query = GTLQueryCalendar.queryForEventsListWithCalendarId("primary")
query.maxResults = 10
query.timeMin = GTLDateTime(date: NSDate(), timeZone: NSTimeZone.localTimeZone())
query.singleEvents = true
query.orderBy = kGTLCalendarOrderByStartTime
service.executeQuery(
query,
delegate: self,
didFinishSelector: "displayResultWithTicket:finishedWithObject:error:"
)
}
// Display the start dates and event summaries in the UITextView
func displayResultWithTicket(
ticket: GTLServiceTicket,
finishedWithObject response : GTLCalendarEvents,
error : NSError?) {
if let error = error {
showAlert("Error", message: error.localizedDescription)
return
}
var eventString = ""
if let events = response.items() where !events.isEmpty {
for event in events as! [GTLCalendarEvent] {
let start : GTLDateTime! = event.start.dateTime ?? event.start.date
let startString = NSDateFormatter.localizedStringFromDate(
start.date,
dateStyle: .ShortStyle,
timeStyle: .ShortStyle
)
eventString += "\(startString) - \(event.summary)\n"
// An array holding all my upcoming events
listOfEvents.append("\(startString) - \(event.summary)")
print(listOfEvents)
}
} else {
eventString = "No upcoming events found."
}
output.text = eventString
self.tableView.reloadData()
}
// Creates the auth controller for authorizing access to Google Calendar API
private func createAuthController() -> GTMOAuth2ViewControllerTouch {
let scopeString = scopes.joinWithSeparator(" ")
return GTMOAuth2ViewControllerTouch(
scope: scopeString,
clientID: kClientID,
clientSecret: nil,
keychainItemName: kKeychainItemName,
delegate: self,
finishedSelector: "viewController:finishedWithAuth:error:"
)
}
// Handle completion of the authorization process, and update the Google Calendar API
// with the new credentials.
func viewController(vc : UIViewController,
finishedWithAuth authResult : GTMOAuth2Authentication, error : NSError?) {
if let error = error {
service.authorizer = nil
showAlert("Authentication Error", message: error.localizedDescription)
return
}
service.authorizer = authResult
dismissViewControllerAnimated(true, completion: nil)
}
// Helper for showing an alert
func showAlert(title : String, message: String) {
let alert = UIAlertController(
title: title,
message: message,
preferredStyle: UIAlertControllerStyle.Alert
)
let ok = UIAlertAction(
title: "OK",
style: UIAlertActionStyle.Default,
handler: nil
)
alert.addAction(ok)
presentViewController(alert, animated: true, completion: nil)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
print(self.listOfEvents.count)
return self.listOfEvents.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = self.tableView.dequeueReusableCellWithIdentifier("Events Cell", forIndexPath: indexPath) as UITableViewCell
var event = ""
event = listOfEvents[indexPath.row]
cell.textLabel?.text = event
return cell
}
}
I would appreciate any help and insight :-) Thanks so much!

After output.text = eventString, you should reload the tableview.

Related

Can't get variable from Notification?

I want to write a project has a notification can print data which stored in main viewcontroller, but when notification fired, always get empty data.
In the ViewController
arrPerson = [String]()
override func viewDidLoad() {
super.viewDidLoad()
arrPerson.append("Peter")
arrPerson.append("Jack")
setNotification()
}
func printTheName() {
print("In printTheName")
print("arrPerson:\(arrPerson.count)")
for x in arrPerson {
print(x)
}
}
func setNotification() {
let notification = UNMutableNotificationContent()
notification.title = "title"
notification.subtitle = ""
notification.body = "body"
notification.sound = UNNotificationSound.default()
let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 60, repeats: true)
let request = UNNotificationRequest(identifier: "check", content: notification, trigger: trigger)
let notificationCenter = UNUserNotificationCenter.current()
notificationCenter.add(request) { (error) in
if error != nil {
print("notificationCenter.add ERROR:\(error)")
// Handle any errors.
}
}
}
In the Appdelegate
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
print("In userNotificationCenter")
ViewController().printTheName()
}
The code will print out "userNotificationCenter","In printTheName","arrPerson:0".
I need get data from notification. Why arrPerson.count is 0 when call printTheName from notification?
Try to programatically instantiate the viewController using a window in your appdelegate.
You will be able to fetch the count then in your notification center.Or since your viewController class is the landing screen, Call the userNotifationCenter method in your main Class and not here.

Insert information from REST API in a table view

I after asking another question today and fixed my Swift 4.2 code, I realized that I can't debug the app because of some profiles.
Errors shown when Testing application
The app also crashes on launch so there is not much I can do for now. I believe that the issue is how I am getting the information from the webserver (currently my computer). I am quite new to this, so i might have some mistakes in my code, so bear with me.
import UIKit
class InfoTableViewController: UITableViewController {
//MARK: Properties
class Produs {
var nume: String!
var codBare: String!
init(nume: String, codBare: String) {
self.nume = nume
self.codBare = codBare
}
}
var produse = [Produs]()
override func viewDidLoad() {
super.viewDidLoad()
//Load elements from server, theoretically
loadProducts()
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return produse.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// Table view cells are reused and should be dequeued using a cell identifier.
let cellIdentifier = "InfoTableViewCell"
guard let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as? InfoTableViewCell else {
fatalError("The dequeued cell is not an instance of InfoTableViewCell.")
}
// Fetches the appropriate meal for the data source layout.
let produs = produse[indexPath.row]
cell.nameMain.text = produs.nume
cell.nameInfo.text = produs.codBare
return cell
}
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destination.
// Pass the selected object to the new view controller.
}
//MARK: Private Methods
private func loadProducts() { //This function retrieves information in a JSON format from the server
var request = URLRequest(url: URL(string: "192.168.0.145")!)
request.httpMethod = "GET"
URLSession.shared.dataTask(with: request, completionHandler: { data, response, error -> Void in
do {
let decoder = JSONDecoder()
let json = try decoder.decode([[String]].self, from: data!)
print(json)
for produs in json {
print(produs)
var nume_prod: String = produs[0] // Numele produsului
var cod_ext: String = produs[1] // Codul de bare al produsului
var prod_obj = Produs(nume: nume_prod, codBare: cod_ext)
self.produse.append(prod_obj)
}
} catch {
print("JSON Serialization error")
}
}).resume()
}
}
I am getting the information from the server in a JSON file that is an array of arrays and looks like this:
[
[
"product1",
"code1"
],
[
"product2",
"code2"
],
[
"product3",
"code3"
]
]
Thank you for your help!
Don't send the JSON as array of arrays, send it as array of dictionaries. It simplifies the decoding considerably.
[
{"name":"product1", "code":"code1"},
{"name":"product2", "code":"code2"},
{"name":"product3", "code":"code3"}
]
Then declare the model as struct and never declare properties as implicit unwrapped optional which are initialized with non-optional values. If you need optionals declare them as regular optional (?) otherwise non-optional
struct Produs {
let name: String
let code: String
}
Replace loadProducts with
private func loadProducts() { //This function retrieves information in a JSON format from the server
let url = URL(string: "192.168.0.145")!
URLSession.shared.dataTask(with: url, completionHandler: {[unowned self] data, response, error in
if let error = error { print(error); return }
do {
self.produse = try JSONDecoder().decode([Produs].self, from: data!)
print(self.produse)
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch {
print(error)
}
}).resume()
}
And replace cellForRowAt with
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cellIdentifier = "InfoTableViewCell"
let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as! InfoTableViewCell
// Fetches the appropriate meal for the data source layout.
let produs = produse[indexPath.row]
cell.nameMain.text = produs.name
cell.nameInfo.text = produs.code
return cell
}

how to use local datastore to save and query data with parse and swift

In my app. There will be user list and message list as my code below
message list code (load the list from parse)
#IBOutlet var messageTableView: UITableView!
var messageArray:[String] = ["Lope"]
override func viewDidLoad() {
super.viewDidLoad()
retrieveMessages()
}
func retrieveMessages() {
var query = PFQuery(className:"Messages")
var user = PFUser.currentUser()
query.whereKey("user", equalTo:user.objectId)
query.findObjectsInBackgroundWithBlock { [weak self]
(objects:[AnyObject]?, error:NSError?) -> Void in
println(objects)
println("succeed")
let messages = objects
for object in objects!{
if let message = object["messageTextColumn"] as? String {
println(object)
self?.messageArray.append(message)
}
}
self?.tableView.reloadData()
}
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return messageArray.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("messageCell", forIndexPath: indexPath) as UITableViewCell
cell.textLabel?.text = messageArray[indexPath.row]
return cell
}
add message code (add new message to parse)
class addMessageViewController: UIViewController {
#IBOutlet weak var addMessageText: UITextField!
#IBAction func addMessage(sender: AnyObject) {
var newMessage = addMessageText.text
let message = PFObject(className: "Messages")
var user = PFUser.currentUser()
message["messageTextColumn"] = newMessage
message["user"] = user.objectId
message.saveInBackgroundWithBlock {(success: Bool, error: NSError?) -> Void in
if (success) {
println("added to Message Class")
println(user)
message.saveInBackground()
} else {
// Error saving message
}
}
}
I want to use parse local datastore to store these data in my app locally so that my app won't have to use the internet connect all the time and when the user is not connect to the internet the user list and message list will still appear.
The problem is I don't know what method in local datastore should I use where should I put the local datastore code in "add message code" to save the new message and in "message list code" to query it to my app locally and if there's any update, It will do later after our local "message list" has been loaded. Any help is appreciated.
Thanks!
To begin with Parse data store, you need to opt in from your app delegate:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
// Override point for customization after application launch.
// Opt in for Parse Local data store *Before Parse.setApplicationId*
Parse.enableLocalDatastore()
Parse.setApplicationId("YOUR PARSE APP ID",
clientKey: "YOUR PARSE CLIENT ID")
//... other code that you might need when app did finish launching
return true
}
Later when you save a new message you will use:
message.saveEventually()
This will save in the local data store, and eventually (when internet will be available) in the remote data store.
From here you might also be interested in the use of Parse data pinning.
See Parse doc for more.
Hope this helps

How do I setup a sign in page using parse and swift in Xcode (error with 'signInBackgroundWithBlock')?

I'm trying to setup a sign in page using parse and swift in Xcode but I keep getting an error with 'signInBackgroundWithBlock' how do I make this work?
I keep receiving the message
Cannot invoke 'signUpInBackgroundWithBlock' with an argument list of
type ((Bool!, NSError!) -> Void)
so far this is what I have and I just have an error with that part.
import UIKit
import Parse
class EmailLogin: UIViewController, UITextFieldDelegate {
#IBOutlet weak var emailTextField: UITextField!
#IBOutlet weak var statusLabel: UILabel!
#IBOutlet weak var createAccountButton: UIButton!
#IBOutlet weak var passwordTextField: UITextField!
override func viewDidLoad()
{
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
emailTextField.delegate = self;
passwordTextField.delegate = self;
}
override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func createAccountButtonPressed(sender: AnyObject)
{
if verifyEmailDomain(self.emailTextField.text)
{
createAccount(self.emailTextField.text, password: self.passwordTextField.text)
}
else
{
//self.statusLabel.text = "Email domain is not valid.";
let alert = UIAlertView()
alert.title = "Invalid Email Domain"
alert.message = "Make sure you entered in your address correctly. If you did, ask your system about using PageMD! Thanks."
alert.addButtonWithTitle("Close")
alert.show()
}
}
func verifyEmailDomain(email: String) -> Bool
{
var isVerifiedDomain = false
let userDomain: String = (email.componentsSeparatedByString("#")).last!
//NSLog(userDomain)
let validDomainsFileLocation = NSBundle.mainBundle().pathForResource("ValidDomains", ofType: "txt")
var validDomainsFileContent = NSString(contentsOfFile: validDomainsFileLocation!, encoding: NSUTF8StringEncoding, error: nil)
//NSLog(validDomainsFileContent!)
let validDomains = validDomainsFileContent!.componentsSeparatedByString("\n")
for domain in validDomains
{
NSLog(domain as! NSString as String)
if userDomain == (domain as! NSString)
{
isVerifiedDomain = true
break
}
}
return isVerifiedDomain
}
func createAccount(email: String, password: String)
{
var newUser = PFUser()
newUser.username = email // We want the user to login only with their email.
newUser.email = email
newUser.password = password
//this where i get my error//
newUser.signUpInBackgroundWithBlock { (succeeded: Bool!, error: NSError!) -> Void in
if error == nil
{
// Account created successfully!
if succeeded == true
{
self.statusLabel.text = "Account created!"
}
}
else
{
if let errorField = error.userInfo
{
self.statusLabel.text = (errorField["error"] as NSString)
}
else
{
// No userInfo dictionary present
// Help from http://stackoverflow.com/questions/25381338/nsobject-anyobject-does-not-have-a-member-named-subscript-error-in-xcode
}
}
}
}
func textFieldShouldReturn(textField: UITextField) -> Bool
{
textField.resignFirstResponder()
return true;
}
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
If you are using swift 1.2 (Xcode 6.3) you need to call the function by:
newUser.signUpInBackgroundWithBlock({(succeeded:Bool, error:NSError?) -> Void in
})
And if you are using swift 1.1 (Xcode 6.1, 6.2) you need to call the function by:
newUser.signUpInBackgroundWithBlock({(succeded:Bool, error:NSError!) -> Void in
})
This is different because of the swift update 1.2 which has changes with using optionals.
Another way is to write it like this:
(Works in old and new swift)
newuser.signUpInBackgroundWithBlock { (succeded, error) -> Void in
}

You need to specify a parseClassName for the PFQueryTableViewController

I created a tableViewcontroller and assigned it the custom class: PFQueryTableViewController in story board. I then also gave it the parseClassName "userMessage" and for some reason when i try to run the application I always get the same error message: NSInternalInconsistencyException', reason: 'You need to specify a parseClassName for the PFQueryTableViewController.
I dont understand why I am getting this error because I explicitly gave the class a parseClassName.
Here is my associated code for the PFQueryTabletableViewController:
import UIKit
import CoreLocation
import Parse
class TableViewController: PFQueryTableViewController, CLLocationManagerDelegate {
let userMessages = ["blah blahh blahhh", "Beep Beep Boop", "Beep Beep Bobbity boop"]
let locationManager = CLLocationManager()
var currLocation: CLLocationCoordinate2D?
override init!(style: UITableViewStyle, className: String!) {
super.init(style: style, className: className)
}
required init(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
self.parseClassName = "userMessage"
self.textKey = "text"
self.pullToRefreshEnabled = true
self.objectsPerPage = 40
}
private func alert(message: String){
let alert = UIAlertController(title: "Uh-OH", message: message, preferredStyle: UIAlertControllerStyle.Alert)
let action = UIAlertAction(title: "Ok", style: UIAlertActionStyle.Default, handler: nil)
let cancel = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler: nil)
let settings = UIAlertAction(title: "Settings", style: UIAlertActionStyle.Default) {(action) -> Void in
UIApplication.sharedApplication().openURL(NSURL(string: UIApplicationOpenSettingsURLString)!)
return
}
alert.addAction(settings)
alert.addAction(action)
self.presentViewController(alert, animated: true, completion: nil)
}
override func viewDidLoad() {
super.viewDidLoad()
self.tableView.estimatedRowHeight = 120
self.tableView.rowHeight = 120
locationManager.desiredAccuracy = 100
locationManager.delegate = self
locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func locationManager(manager: CLLocationManager!, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
alert("Cannot fetch your location!!")
}
override func queryForTable() -> PFQuery! {
let query = PFQuery(className: "Messages")
if let queryLoc = currLocation {
query.whereKey("location", nearGeoPoint: PFGeoPoint(latitude: queryLoc.latitude, longitude: queryLoc.longitude), withinMiles: 1)
query.limit = 40
query.orderByDescending("createdAt")
}else {
query.whereKey("location", nearGeoPoint: PFGeoPoint(latitude: 37.41182, longitude: -121.941125), withinMiles: 1)
query.limit = 40
query.orderByDescending("createdAt")
}
return query
}
func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {
locationManager.stopUpdatingLocation()
if(locations.count > 0) {
let location = locations[0] as CLLocation
println(location.coordinate)
currLocation = location.coordinate
} else {
alert("Cannot fetch your loation")
}
}
override func objectAtIndexPath(indexPath: NSIndexPath!) -> PFObject! {
var obj : PFObject? = nil
if(indexPath.row < self.objects.count) {
obj = self.objects[indexPath.row] as? PFObject
}
return obj
}
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return userMessages.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath!, object: PFObject!) -> PFTableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as TableViewCell
cell.messageText.text = object.valueForKey("text") as? String
cell.messageText.numberOfLines = 0
let views = object.valueForKey("count") as Int
cell.numberOfViewsLabel.text = "\(views)"
cell.numberOfViewsLabel.text = "\((indexPath.row + 1) * 5)"
return cell
}
func addToViews(sender: AnyObject) {
let hitPoint = sender.convertPoint(CGPointZero, toView: self.tableView)
let hitIndex = self.tableView.indexPathForRowAtPoint(hitPoint)
let object = objectAtIndexPath(hitIndex)
object.incrementKey("count")
object.saveInBackgroundWithBlock { (Bool, NSError) -> Void in
//blahhh
}
self.tableView.reloadData()
}
}
`
parseClassName is a readonly variable and is only used when subclassing PFObject.
https://parse.com/docs/ios/api/Classes/PFObject.html#//api/name/parseClassName
The class name of the object.
#property (strong, readonly) NSString *parseClassName
Declared In
PFObject.h
Obj-C
#implementation MYGame
#dynamic title;
+ (NSString *)parseClassName {
return #"Game";
}
#end
Swift
class MYGame: PFObject {
class func parseClassName() -> String! {
return "Game"
}
}
In my case I had used a storyboard and needed to create an initWithCoder: method in my PFQueryTableViewController subclass. The template pointed to in the Parse.com docs lacks this method, but the first comment following the example does include an example implementation: https://gist.github.com/jamesyu/ba03c1a550f14f88f95d#gistcomment-74202
The message "You need to specify a parseClassName for the PFQueryTableViewController" is being generated because none of the methods are setting the PFQueryTableViewController's parseClassName property. You'll note that the property is defined quite plainly in the initWithStyle: method example provided in the docs. But, that method won't be called if the view is loaded via a storyboard: for that you'll need to set parseClassName in the initWithCoder: method.
Also, don't confuse subclassing a PFQueryTableViewController for a PFObject. For a PFObject you need to create a class method called parseClassName and also register the subclass before calling [Parse setApplicationId:aid clientKey:ckey]. You don't do those things for a PFQueryTableViewController or any of the other ParseUI view controllers. They rely on one or more of the init methods.

Resources