i try to create my first application on Xcode ,first I tried only to overwrite the text of a label at same moment when it is write in a TextField.
Now I try just for fun , to set hidden a second label (Label2) from Utility area and with the button ok to keep these unhide but the I'll give error (Thread 1 :breakpoint 1.1).
After I try solve the problem, I think to save the text in a var String and when I press the "ok" button , it set the Label2.text=String.
Anyway ,When I build and run this code it give the same ERROR .
Anyone can help me ?
thanks
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var labelTitle: UILabel!;
#IBOutlet weak var labelRes: UILabel!;
#IBOutlet weak var textReceveirer: UITextField!;
var myString : String = " "
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func button(_ sender: UIButton) {
myString=textReceveirer.text!
labelRes.text = "hello \(myString)"
}
}
Try with the following code:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var labelOne: UILabel!;
#IBOutlet weak var textReciver: UITextField!;
override func viewDidLoad() {
super.viewDidLoad()
labelOne.text = " "
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func button(_ sender: UIButton) {
labelOne.text = textReciver.text
}
}
I think the error is at line
var String=""
String is data type ,
if you want to create variable type of string you may use follow this
var myVariable : String = ""
write in your code var String=""that replace with
var Variable : String = ""
or check that connection inspector..
Related
I'm having difficulty with IBOutlets. I'm trying to allow the user to input a goal (called nameOfRewardText) in a table view controller (LoLAddGoalsTableViewController) and then when they click "Done", have that goal show up in a label called "currentGoalTextField" in a different view controller (LoLGoalViewController). I had been trying to implement this using a Save segue, but was advised to use a protocol with a delegate instead (Updating text in ViewController using Save function). Now that I've replaced the Save segue with the protocol and delegate, the inputted "nameOfRewardText" text is not showing up in the "currentGoalTextField" label, I suspect because the IBOutlets are no longer tied together properly. I've attached the code and screenshots of the Outlets below to try to clarify where I'm at. Does anyone know how I could fix the IBOutlets or if there's something else I need to add to get this working? I deleted the line where I assign nameOfRewardText.text to be goal.goalText, so I think nameOfRewardText isn't getting assigned to var goal? Maybe I'm using too many names for this text (nameOfRewardText, goalText, and currentGoalTextField) and that's complicating things? Any help at all would be greatly appreciated, as I'm very new to this! Thank you everybody!
Here is the struct goal:
import UIKit
struct Goal {
var goalText: String
var pointsToCompleteGoal: Int
var pointsEarnedTowardsGoal: Int
var repeatGoal: Bool
init(goalText: String, pointsToCompleteGoal: Int, pointsEarnedTowardsGoal: Int, repeatGoal: Bool = false) { //Made String non-optional. If issue later, can revert.
self.goalText = goalText
self.pointsToCompleteGoal = pointsToCompleteGoal
self.pointsEarnedTowardsGoal = pointsEarnedTowardsGoal
self.repeatGoal = repeatGoal
}
}
Here is the public protocol:
import Foundation
import UIKit
protocol GoalDelegate: class {
func passGoal(_ goal: Goal?)
}
Here is where the delegate is created, and as you can see, the statement where I assign nameOfRewardText.text to be goal.goalText is now gone:
import UIKit
class AddGoalsTableViewController: UITableViewController {
var goal:Goal?
var delegate: GoalDelegate?
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// HASHED OUT THE BELOW BECAUSE REPLACING WITH DELEGATE:
// if segue.identifier == "SaveGoal" {
// let pointsNeededInt = Int(pointsNeededText.text!)
// let pointsEarnedInt = Int(goalProgressText.text!)
// goal = Goal(goalText: nameOfRewardText.text!, pointsToCompleteGoal: pointsNeededInt!, pointsEarnedTowardsGoal: pointsEarnedInt!)
// }
if let secondViewController = segue.destination as? LoLGoalViewController{
delegate = secondViewController
delegate?.passGoal(goal)
}
}
#IBOutlet var goalTableTitleText : UILabel!
#IBOutlet weak var goalProgressText: UILabel!
#IBOutlet weak var nameOfRewardText: UITextField!
#IBOutlet weak var pointsNeededText: UITextField!
#IBOutlet weak var repeatSwitch: UISwitch!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
Screen cap of AddGoalsTableViewController with Outlets:
Here I conform to the protocol and call the function passGoal:
import UIKit
class LoLGoalViewController: UIViewController, GoalDelegate {
#IBOutlet weak var currentGoalTextField: UILabel!
func passGoal(_ goal: Goal?) {
currentGoalTextField.text = goal?.goalText
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
extension LoLGoalViewController {
#IBAction func cancelToLoLGoalViewController(_ segue: UIStoryboardSegue) {
}
}
Screen cap of LoLGoalViewController with Outlets:
Your LoLGoalViewController view controller might not have fully loaded with all of its outlets. Adding on to my answer to your previous question, you can declare another variable in LolGoalViewController:
#IBOutlet weak var currentGoalTextField: UILabel!
var goalText: String = ""
In your passGoal method, set your string to the goalText variable instead of the label's text:
func passGoal(_ goal: Goal?) {
goalText = goal?.goalText
}
Lastly, in your viewDidLoad of LolGoalViewController, set the label text to be goalText:
override func viewDidLoad() {
super.viewDidLoad()
currentGoalTextField.text = goalText
}
I want to create a simple BMI calculator using height and weight and I am having trouble converting my UITextField strings to integers for the calculation.
Here's my working code:
import UIKit
class BMICalculator: UIViewController {
//MARK: Properties
#IBOutlet weak var weightField: UITextField!
#IBOutlet weak var heightField: UITextField!
#IBOutlet weak var solutionTextField: UILabel!
#IBAction func calcButton(_ sender: AnyObject) {
let weightInt = Int(weightField)
let heightInt = Int(heightField)
solutionTextField.text = weightInt/(heightInt*heightInt)
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Anyone have any ideas? I tried searching for the solution but couldn't find anything specific to this issue.
Use this:
guard let text1 = weightField.text else {
return
}
guard let text2 = heightField.text else {
return
}
guard let weightInt = Int(text1) else {
return
}
guard let heightInt = Int(text2) else {
return
}
solutionTextField.text = weightInt /(heightInt*heightInt)
//Change your name for this outlet 'solutionTextField' to 'solutionLabel' since it is a UILabel not UITextField
The TextField only accepts a String, it wont take an Int.
Change this:
solutionTextField.text = weightInt/(heightInt*heightInt)
To this:
solutionTextField.text = String(weightInt/(heightInt*heightInt))
I don't think your code is working. To get the values out of your UITextFields and convert them to Ints, you'll need to pull them out of the '.text properties. Then, when you calculate the result, you'll need to convert it back to a string and set solutionTextField?.text equal to that result.
class BMICalculator: UIViewController {
//MARK: Properties
#IBOutlet weak var weightField: UITextField!
#IBOutlet weak var heightField: UITextField!
#IBOutlet weak var solutionTextField: UILabel!
#IBAction func calcButton(_ sender: AnyObject) {
let weightInt = Int((weightField?.text!)!)
let heightInt = Int((heightField?.text!)!)
let solution = weightInt!/(heightInt!*heightInt!)
solutionTextField?.text = "\(solution)"
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Keep in mind that this code is very dangerous because you're not safely unwrapping optionals, but that's a different thread.
Hope this helps.
Good morning!
I have an "unable to load" problem in my iOS widget. I've read a lot of about the "unable to load" message but nothing fixed my problem. I'm not sure but I think my problem is to refresh the widget after changing my content.
My widget has one button and one label. If the user press the button the text from the label will changed - in this moment the widget shows "unable to load". Just a milisecond after pressing the button.
import UIKit
import NotificationCenter
class TodayViewController: UIViewController, NCWidgetProviding {
#IBOutlet var segment_att: UISegmentedControl!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func widgetPerformUpdateWithCompletionHandler(completionHandler: ((NCUpdateResult) -> Void)) {
completionHandler(NCUpdateResult.NewData)
}
func widgetMarginInsetsForProposedMarginInsets(defaultMarginInsets: UIEdgeInsets) -> UIEdgeInsets {
return UIEdgeInsetsZero
}
#IBAction func button_ae(sender: AnyObject) {
let tableviewclass = TodayTableViewController()
tableviewclass.newData()
}
}
Important is that the label is shown in a TableViewCell of a TableViewController. So the TableViewController is embeded in the ViewController within a Container... The listener from the button call the method newdata() of the file of the TableViewController.
import UIKit
import NotificationCenter
class TodayTableViewController: UITableViewController, NCWidgetProviding {
#IBOutlet var table: UITableView!
#IBOutlet var label1: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
init()
}
func init() {
let meldung: String = "test"
label1.text = meldung
}
func newData() {
let meldung: String = "new test"
label1.text = meldung
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
The code is really simple and basic - so I'm wondering about the problem in this simple mechanism. I hope you can help me!
Thanks at all!
Your code assumes that label1 has been set when newData() is called, even immediately after the constructor is called.
Try using this optional chaining syntax instead, which will quietly fail if the property is nil:
import UIKit
import NotificationCenter
class TodayTableViewController: UITableViewController, NCWidgetProviding {
#IBOutlet var table: UITableView!
#IBOutlet var label1: UILabel!
var meldung: String = "test" // <-- meldung is property
override func viewDidLoad() {
super.viewDidLoad()
init()
}
func init() {
label1?.text = melding // <-- optional chaining
}
func newData() {
melding = "new test" // <-- set the class property
label1?.text = meldung // <-- optional chaining
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
and instead of calling newData(), you might instead just set the meldung property, e.g.:
tableviewclass.meldung = "new test"
as your viewDidLoad() will take care of setting the UILabel text from the property
I've done plenty of searching but am not finding the answer to my question.
My two UITextFields fields are resetting using the clear function. The UILabel retains the original value from the printWatts function, doesn't clear. Would appreciate any advice to resolve this small issue as I learn Swift. Thanks!
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var inputFeet: UITextField!
#IBOutlet weak var inputWatts: UITextField!
#IBOutlet weak var resultsLabel: UILabel!
var stripFeet = ""
var wattValue = ""
var totalWatts : Float = 0.0
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func submitButton(sender: AnyObject) {
calculateWatts()
}
#IBAction func clearButton(sender: AnyObject) {
clear()
}
func calculateWatts() {
if let stripFeet = inputFeet.text,
wattValue = inputWatts.text,
fstripFeet = Float(stripFeet),
fwattValue = Float(wattValue){
totalWatts = fstripFeet * fwattValue
}
printWatts()
}
func printWatts() {
let formatWatts = String(format: "%0.2f", totalWatts)
resultsLabel.text = "Total watts: \(formatWatts)"
}
func clear(){
inputFeet.text = ""
inputWatts.text = ""
self.resultsLabel.text = ""
}
}
Thanks to #Eendje for suggesting that I check my connections. I had the submit and clear actions both connected to my submit button. Option drag is too convenient. All good now.
import UIKit
class SecondViewController: UIViewController {
#IBOutlet weak var labelA: UILabel!
#IBOutlet weak var labelB: UILabel!
var dataPassed:String!
var secondDataPassed:String!
var newVar: String!
var newVar2: String!
override func viewDidLoad() {
super.viewDidLoad()
labelA.text = dataPassed
labelB.text = secondDataPassed
newVar = labelA.text
println(newVar)
}
println(newVar) *** I can't access newVar outside override func viewDidLoad() { - Gives "expected declaration" Its driving me crazy!!!***
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Is there any data in dataPassed? If you don't assign any String to your dataPassed variable, and then you assign newVar to dataPassed, newVar will have nothing to print.
Try:
import UIKit
class SecondViewController: UIViewController {
#IBOutlet weak var labelA: UILabel!
#IBOutlet weak var labelB: UILabel!
var dataPassed:String! = "Test."
var secondDataPassed:String!
var newVar: String!
var newVar2: String!
override func viewDidLoad() {
super.viewDidLoad()
labelA.text = dataPassed
labelB.text = secondDataPassed
newVar = labelA.text
println(newVar)
}
Secondly, it appears that you're trying to println again outside of the function. That isn't going to work, because viewDidLoad is essentially the "main method" of your app. You can create other functions that respond to button touches, etc... and run a println there, but because Swift code is executed functionally, the code you're executing has to be inside of a particular function. While you can declare variables, as you have, you can't perform actions such as printing them outside of a function, because then there's no order/method to the madness.
The only place where you can run Swift code on a standalone basis without functions is in a Swift Playground. In XCode you can select File -> New -> Playground to try this out.