The func yesBtSetTextTo prints not nil when called from the grey button in the pink area, but the same func print nil when is called from the yellow button. I am lost on this one.
My main veiwController.swift does not have a prepareForSegue since I did not thing it is needed here.
The func in question is at the end of this code block,
MainBtVC.swift
protocol MainBtDelegate {
func yesBtSetTextTo(name: String)
}
class MainBtVC: UIViewController, MainBtDelegate {
#IBOutlet weak var yesBt: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func yesBtSetTextTo(name: String) {
print("called")
if yesBt == nil {
print("button is nil")
} else {
print("button not nil")
}
// yesBt.setTitle("Exit", forState: UIControlState.Normal)
}
#IBAction func yesBtTapped(sender: AnyObject) {
yesBtSetTextTo("dummy")
}
TopVC.swift
class TopVC: UIViewController {
var delegate: MainBtDelegate?
override func viewDidLoad() {
super.viewDidLoad()
delegate = MainBtVC()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func buttonTapped(sender: AnyObject) {
delegate?.yesBtSetTextTo("Exit")
}
Related
I want to let the people login to the certain domain, but it always shows a error.
Cannot convert value of type 'String' to expected argument type 'Int').
how can I deal with it?
import UIKit
import FirebaseAuth
class ViewController: UIViewController {
#IBOutlet var emailTextField: UITextField!
#IBOutlet var passwordTextField: UITextField!
#IBAction func signUp(_ sender: Any) {
Auth.auth().createUser(withEmail: emailTextField.text!, password: passwordTextField.text!) { (result, error) in
if error != nil{
print(error)
}else{
self.performSegue(withIdentifier: "createdUser", sender: self)
}
}
}
#IBAction func signIn(_ sender: Any) {
Auth.auth().signIn(withEmail: emailTextField.text!, password: passwordTextField.text!) { (result, error) in
if error != nil{
print(error)
}else{
var hi = self.emailTextField.text
if hi?.suffix("#hkugac.edu.hk"){ //error here
self.performSegue(withIdentifier: "logged", sender: self)
}
}
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
}
Try using the hasSuffix method. https://developer.apple.com/documentation/swift/string/1541149-hassuffix
var hi = self.emailTextField.text
if let mail = hi, mail.haSuffix("#hkugac.edu.hk")
{
self.performSegue(withIdentifier: "logged", sender: self)
}
else
{
// Dome some error handling here.
}
Also, I think it would be better to check the mail before you call the signIn function.
I am trying to download an image from my web server, using Xcode 8 and Swift 3. It looks like this. The request returns nil. Any suggestions why?
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var view1: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func load(_ sender: UIButton) {
let url = URL(string:"http://www.example.com/folder2/pic3-1.jpg")
let task = URLSession.shared.dataTask(with: url!) { data, response,
error in
guard let data = data, error == nil else { return }
DispatchQueue.main.sync() {
self.view1.image = UIImage(data: data)
}
}
task.resume()
}
#IBAction func reset(_ sender: UIButton) {
self.view1.image="blankU.png"
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
Any idea why the image is returning nil from the server?
The Xcode8, Swift3 coding is okay. The server is blocked.
Hi I am brand new to swift and need some help
Every time I run my code my app crashes and spits out a " the above error
Can anyone please tell me what I need to do or what I need to replace in my code?
import UIKit
class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource{
#IBOutlet weak var picker: UIPickerView!
var employeeNames = ["John","Jane","Jack","James"]
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.picker.delegate = self
self.picker.dataSource = self
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return employeeNames.count
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return employeeNames [row]
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
print(employeeNames[row])
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Your code is absolutely fine, so the only alternative is that you haven't hooked up your pickerView outlet. Ctrl click on your picker view in the storyboard and see if your outlet 'picker' shows up. If it doesn't then ctrl drag from the pickerView to your outlet to hook it up.
I have a swift project with a custom cell from a tableview, ans inside it I have a label to display the value of a UIPicker. The UiPicker appear in the keyboard when you press the label, I wan't to be able to set default values to my UIPicker, I tried a lot of differents technics with the 2 methods :
selectRow(), without success, here is my CustomCell code :
import UIKit
class CustomCell: UITableViewCell, UIPickerViewDataSource, UIPickerViewDelegate {
#IBOutlet weak var answer: UITextField!
var delegate: QuestionSelectorCellDelegate?
var pickOption: [String] = []
var pickerView:UIPickerView = UIPickerView()
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
#IBAction func editBeginQuestionSelectorCell(sender: UITextField) {
pickerView = UIPickerView()
pickerView.delegate = self
sender.inputView = pickerView
}
func displayBlock(block: Block){
if block.answers != nil {
pickOption = block.answers! // block.answers! = ["blue","red","green"] for example
}
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return pickOption.count
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return pickOption[row]
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if row < pickOption.count {
answer.text = pickOption[row]
delegate?.updateQuestionSelectorCell(self, rep: pickOption[row])
}
}
}
Updated your code.
You didn't set the pickerView.dataSource!
If i understood your question, you want an element to be selected by default, other than element at index 0.
I also added that.
import UIKit
class CustomCell: UITableViewCell, UIPickerViewDataSource, UIPickerViewDelegate {
#IBOutlet weak var answer: UITextField!
var delegate: QuestionSelectorCellDelegate?
var pickOption: [String] = []
var pickerView:UIPickerView = UIPickerView()
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
#IBAction func editBeginQuestionSelectorCell(sender: UITextField) {
pickerView = UIPickerView()
pickerView.delegate = self
// --- Thats what I added ---
pickerView.dataSource = self
let indexOfDefaultElement = 1 // Make sure that an element at this index exists
pickerView.selectRow(indexOfDefaultElement, inComponent: 0, animated: false)
sender.inputView = pickerView
}
func displayBlock(block: Block){
if block.answers != nil {
pickOption = block.answers! // block.answers! = ["blue","red","green"] for example
}
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return pickOption.count
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return pickOption[row]
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
if row < pickOption.count {
answer.text = pickOption[row]
delegate?.updateQuestionSelectorCell(self, rep: pickOption[row])
}
}
}
I have the following code that loads a video and loops it. However, when pressing home and returning to the application the video freezes and will not play again. I feel like the answer is in the AppDelegate functions but can not seem to get them to work.
import UIKit
import AVKit
import AVFoundation
class ViewController: UIViewController, UIApplicationDelegate {
var videoPlayer: AVPlayer!
var playerLayer: AVPlayerLayer?
override func viewDidLoad() {
super.viewDidLoad()
let path = NSBundle.mainBundle().pathForResource("video", ofType:"mp4")
let url = NSURL(fileURLWithPath: path!)
let playerItem = AVPlayerItem(URL: url)
self.videoPlayer = AVPlayer(playerItem: playerItem)
self.playerLayer = AVPlayerLayer(player: self.videoPlayer)
self.playerLayer!.frame = self.view.frame
self.videoPlayer!.play()
self.view.layer.addSublayer(self.playerLayer!)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("playerDidReachEnd:"), name: AVPlayerItemDidPlayToEndTimeNotification, object:nil)
}
func playerDidReachEnd(notification: NSNotification) {
self.videoPlayer.seekToTime(kCMTimeZero)
self.videoPlayer.play()
}
func applicationWillResignActive(application: UIApplication) {
videoPlayer.pause()
}
func applicationDidBecomeActive(application: UIApplication) {
videoPlayer.play()
}
func applicationDidEnterBackground(application: UIApplication) {
videoPlayer.pause()
}
func applicationWillEnterForeground(application: UIApplication) {
videoPlayer.play()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
Here is what I used to fix it.
import UIKit
import AVKit
import AVFoundation
class ViewController: UIViewController, UIApplicationDelegate {
var videoPlayer: AVPlayer!
var playerLayer: AVPlayerLayer?
override func viewDidLoad() {
super.viewDidLoad()
let path = NSBundle.mainBundle().pathForResource("video", ofType:"mp4")
let url = NSURL(fileURLWithPath: path!)
let playerItem = AVPlayerItem(URL: url)
self.videoPlayer = AVPlayer(playerItem: playerItem)
self.playerLayer = AVPlayerLayer(player: self.videoPlayer)
self.playerLayer!.frame = self.view.frame
self.videoPlayer!.play()
self.view.layer.addSublayer(self.playerLayer!)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("continueVideo:"), name: "continueVideo", object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("playerDidReachEnd:"), name: AVPlayerItemDidPlayToEndTimeNotification, object:nil)
}
func playerDidReachEnd(notification: NSNotification) {
self.videoPlayer.seekToTime(kCMTimeZero)
self.videoPlayer.play()
}
func continueVideo(notification: NSNotification) {
self.videoPlayer.play()
}
func applicationWillResignActive(application: UIApplication) {
videoPlayer.pause()
}
func applicationDidBecomeActive(application: UIApplication) {
videoPlayer.play()
}
func applicationDidEnterBackground(application: UIApplication) {
videoPlayer.pause()
}
func applicationWillEnterForeground(application: UIApplication) {
videoPlayer.play()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
And the app delegate portion
import UIKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
return true
}
func applicationWillResignActive(application: UIApplication) {
}
func applicationDidEnterBackground(application: UIApplication) {
}
func applicationWillEnterForeground(application: UIApplication) {
NSNotificationCenter.defaultCenter().postNotificationName ("continueVideo", object:nil)
}
func applicationDidBecomeActive(application: UIApplication) {
}
func applicationWillTerminate(application: UIApplication) {
}
}
This is a simple fix, you need to create a NSNotification and call it from your AppDelegate:
func applicationWillEnterForeground(application: UIApplication) {
NSNotificationCenter.defaultCenter().postNotificationName("continueVideo", object: nil)
}
SWIFT3 Update
func applicationWillEnterForeground(_ application: UIApplication) {
// NOTE: Notification.Name raw value should be global
NotificationCenter.default.post(name: Notification.Name(rawValue: "com.yourappname.continueVideo"), object:self)
}
And the receive that notification in the normal way:
NSNotificationCenter.defaultCenter().addObserver(self, selector: "<funcName>:", name: "continueVideo", object: nil)
SWIFT3 Update
NotificationCenter.default.addObserver(self, selector: #selector(<funcName>), name: Notification.Name(rawValue: "com.yourappname.continueVideo"), object: nil)