I am trying to make a picker view in Watch Kit from -273 to 273. Sadly Watch Kit only allows a string as title so I converted my range using .map Now when I run the App it display a range from 0 to 546, but will not go into the negative range I tried changing both values but the picker always starts at 0 and won't go back further.
I isolated the problem into these lines:
let pickerItems: [WKPickerItem] = (-273...273).map {
let pickerItem = WKPickerItem()
pickerItem.title = "\($0)"
return pickerItem
}
I just tried it out and your code does show negative values in the picker. Then when the user picks a value you have to take the value and use it to retrieve the "real" value from your pickerItems array:
class InterfaceController: WKInterfaceController {
#IBOutlet var picker: WKInterfacePicker!
var pickerItems: [WKPickerItem]?
override func awakeWithContext(context: AnyObject?) {
super.awakeWithContext(context)
pickerItems = (-273...273).map {
let pickerItem = WKPickerItem()
pickerItem.title = "\($0)"
return pickerItem
}
picker.setItems(pickerItems)
}
#IBAction func pickerDidChange(value: Int) {
let pickedItem = pickerItems![value] // value = 0..576
if let pickedValue = Int(pickedItem.title!) {
print(pickedValue) // -273..273
}
}
}
Related
We have for example segmented control, and array of buttons. If we select one of button in one segment - button need to save state, and than we move to another segment and choose another button. but if we back to previous button - it should be in the position we chose earlier.
that is, each of the segments must store the state of the buttons.
how to do it better?
struct SegmentsModel {
let title: String
var answered: Bool
var buttonIndex: Int? = nil
}
#objc private func buttonsTapped(_ sender: UIButton) {
let _ = buttons.map({$0.isSelected = false})
sender.isSelected = true
guard let index = buttons.firstIndex(of: sender) else { return }
switch index {
case 0:
selectedSegment(segmentedControl, buttonSelected: true, indexButton: 0)
case 1:
selectedSegment(segmentedControl, buttonSelected: true, indexButton: 1)
case 2:
selectedSegment(segmentedControl, buttonSelected: true, indexButton: 2)
case 3:
selectedSegment(segmentedControl, buttonSelected: true, indexButton: 3)
default:
break
}
}
#objc private func selectedSegment(_ sender: UISegmentedControl,
buttonSelected: Bool, indexButton: Int) {
let currentIndex = sender.selectedSegmentIndex
if buttonSelected == true {
buttons[indexButton].isSelected = true
} else {
let _ = buttons.map({$0.isSelected = false})
}
switch currentIndex {
case 0:
arrayOfSegments[0].answered = buttonSelected
arrayOfSegments[0].buttonIndex = indexButton
case 1:
arrayOfSegments[1].answered = buttonSelected
arrayOfSegments[1].buttonIndex = indexButton
case 2:
arrayOfSegments[2].answered = buttonSelected
arrayOfSegments[2].buttonIndex = indexButton
default:
break
}
}
As I mentioned in my comments, there are many ways to achieve what you want. I will share one idea with you.
I see that you tried to store all your buttons in an array and had to keep looping over them to figure out which button was selected previously. Since you want the code to have simpler logic, I will give you a different idea.
One way to achieve what you want is using tags. Every UIView object has a tag and the default is set to 0.
Using storyboard I set the tag of the buttons to 100, 101, 102, 103 and this can be done programmatically also.
You can choose any integers that you like but it is important to give them some unique numbers so when you try to get a view by tag, you get only the view you want.
So after setting the tags, this is what I updated in the code.
struct SegmentsModel {
let title: String
var answered = false
var buttonIndex: Int? = nil
{
// Auto-update the value of answered when value of buttonIndex changes
didSet
{
answered = buttonIndex != nil
}
}
}
I did not do any major updates here. I only added a property observer so when the button index gets set, the answered variable also is auto set so you don't have to anything more for this
Next, below is all the logic to manage the segments and the buttons. I used UIViewController with a StoryBoard so you might need to ignore somethings.
All the important code has comments so you can follow along.
class ViewController: UIViewController {
// I will store the results in this array
var storedResults: [SegmentsModel] = []
// Segment control outlet
#IBOutlet weak var segmentControl: UISegmentedControl!
// Array of buttons
#IBOutlet var buttons: [UIButton]!
override func viewDidLoad() {
super.viewDidLoad()
// Loop over all segments
for index in 0 ..< segmentControl.numberOfSegments
{
// Initialize and store default results values in storedResults array
if let segmentTile = segmentControl.titleForSegment(at: index)
{
storedResults.append(SegmentsModel(title: segmentTile))
}
}
}
// Segment action
#IBAction func selectedSegment(_ sender: UISegmentedControl)
{
// Update the UI of buttons
reloadButtons()
}
#IBAction func buttonTapped(_ sender: UIButton)
{
// Reset your buttons
let _ = buttons.map({$0.isSelected = false})
// Set the current button to selected
sender.isSelected = true
// Get the current result so we can update it
var currentResult = storedResults[segmentControl.selectedSegmentIndex]
// Update the current segments selected button index using tag
currentResult.buttonIndex = sender.tag
// Put the result back into the array as structs as value types
storedResults[segmentControl.selectedSegmentIndex] = currentResult
}
// Reload button data
private func reloadButtons()
{
// Reset your buttons
let _ = buttons.map({$0.isSelected = false})
let currentResult = storedResults[segmentControl.selectedSegmentIndex]
// Check if current index has a selected button and if it does retrieve it
// with a tag
if let selectedButtonIndex = currentResult.buttonIndex,
let selectedButton = view.viewWithTag(selectedButtonIndex) as? UIButton
{
// Show the selected button in the UI
selectedButton.isSelected = true
}
}
}
The end result achieved can be seen in this youtube video which I believe is what you wanted.
I have a list of UITextFields in an Array for users to key in phone numbers. When I click the Send Button, it will connect with my server to send an automated message to the numbers listed. This portion works well. What I want to do now is to check which of the UITextFields has a phone number in it and to check if it has the prefix + before it connects to my server. If any of the UITextField has a phone number without the prefix +, the border color of that UITextField should change colours. If the UITextField does not have a phone number, no action should be taken. How do I go about achieving that?
This is the portion of the code that I need help in
#IBAction func sendbutton(_ sender: Any) {
var numArray: Array<Any>
numArray = [phonenumber.text!, phonenumber1.text!, phonenumber2.text!, phonenumber3.text!]
let myColor = UIColor.red
for num in numArray {
if (num as AnyObject).hasPrefix("+") {
print("Has + symbol")
} else {
print("Does Not Have Symbol")
}
}
You can traverse over the array of textFields and for each textField validate the text for first character is "+". If not set its borderColor.
var textFields = [phonenumber, phonenumber1, phonenumber2, phonenumber3]
var numArray = [String]()
textFields.forEach {
if let text = $0.text, text.first == "+" {
numArray.append(text)
$0.layer.borderWidth = 0.0 //To reset the textField if it didn't validate earlier
} else {
$0.layer.borderColor = UIColor.red.cgColor
$0.layer.borderWidth = 1.0
}
}
I don't think you should loop over an array of strings, instead loop over the text fields so you can set the color directly
var textFields: Array<UITextField> = [phonenumber, phonenumber1, phonenumber2, phonenumber3]
var numbersToSend = [String]()
let myColor = UIColor.red
for textField in textFields {
let number = textField.text ?? ""
if validatePhoneNumber(number) { //extract validation into separate function for clarity
numbersToSend.append(number)
} else {
textField.backgroundColor = myColor //or whatever property you want to change
}
}
Please try this solution i'll work.
private var arrTextFilds = [phonenumber.text ?? "", phonenumber1.text ?? "",
phonenumber2.text!, phonenumber3.text ?? ""]
private var numArray : [String] = []
arrTextFilds {
if let text = $0.text,text.hasPrefix(“+”) {
numArray.append(text)
$0.layer.borderWidth = 0.0
} else {
$0.layer.borderColor = UIColor.red.cgColor
$0.layer.borderWidth = 1.0
}
}
I have a lot of experience working with Matlab, but I only recently started programming in Swift 4. My current project involves building a questionnaire. I have used the ‘drag and drop’ feature in Xcode to produce an #IBAction function for a button in storyboard, which can then lead to pressed button changing its appearance. This functionality is contained within the ButtonResponse class in the code snippet below:
struct ResponseProfile {
var responseArray: Array<String>
init(responseArray: Array<String>) {
self.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
}
mutating func updateArray(_ anArray: Array<String>) -> (Array<String>) {
responseArray = anArray
return responseArray
}
}
class ButtonResponse: UIButton {
var responseVariables: ResponseProfile
var checkedImage = UIImage(named: "checkedResponseBox")! as UIImage
var uncheckedImage = UIImage(named: "uncheckedResponseBox")! as UIImage
required init?(coder aDecoder: NSCoder) {
self.responseVariables = ResponseProfile(
responseArray: []
)
super.init(coder: aDecoder)
}
#IBAction func checkboxTapped(_ sender: UIButton) {
switch sender.accessibilityIdentifier {
case "excellent":
let oldResponseStatus = responseVariables.responseArray[0]
if oldResponseStatus == "unchecked"{
sender.setImage(checkedImage, for: UIControlState.normal)
let oldResponsePresence = responseVariables.responseArray.contains("checked")
if oldResponsePresence == true {
responseVariables.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
}
responseVariables.responseArray[0] = "checked"
} else if oldResponseStatus == "checked" {
sender.setImage(uncheckedImage, for: UIControlState.normal)
responseVariables.responseArray[0] = "unchecked"
}
case "veryGood":
let oldResponseStatus = responseVariables.responseArray[1]
if oldResponseStatus == "unchecked" {
sender.setImage(checkedImage, for: UIControlState.normal)
let oldResponsePresence = responseVariables.responseArray.contains("checked")
if oldResponsePresence == true {
responseVariables.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
}
responseVariables.responseArray[1] = "checked"
} else if oldResponseStatus == "checked" {
sender.setImage(uncheckedImage, for: UIControlState.normal)
responseVariables.responseArray[1] = "unchecked"
}
default: break
}
}
}
I imagined that I could use an array to internally represent the state of the buttons in the user interface (this would be the ‘responseArray’ variable). By changing elements within responseArray following a button press, I thought I could keep track which buttons were pressed and ensure that no more than one button at a time was checked. I incorrectly thought responseArray would be updated, but this is not the case. The array always reverts to its initiation state.
N.B. responseArray contains seven elements because there are seven response options. So far, I have attempted to program only two of the response options: “excellent” and “veryGood”.
In attempting to find a solution, I attempted to simplify the above code in playground:
import UIKit
struct ResponseProfile {
var responseArray: Array<String>
init(responseArray: Array<String>) {
self.responseArray = ["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
}
mutating func updateArray(input anArray: Array<String>) -> (Array<String>) {
responseArray = anArray
return responseArray
}
}
class ButtonResponse {
var responseVariables: ResponseProfile
init(){
self.responseVariables = ResponseProfile(responseArray: [])
}
var responseA = ResponseProfile(responseArray: [])
}
var responseOne = ResponseProfile(responseArray: [])
responseOne.responseArray[0] = "checked" //user performs action resulting in first element being changed from a starting value of "unchecked" to "checked"
responseOne.updateArray(input: responseOne.responseArray)
var responseTwo = ResponseProfile(responseArray:[])
responseTwo.responseArray //responseArray revert to initialization values. How can I keep changes to the responseArray?
How can I update responseArray within the ResponseProfile structure without having to create a new variable to record every change? Is this the problem I should be looking at or is there, on a more general level, a better strategy that I should be taking?
I am surprised that I struggled this much to deal with this issue. I thought the answer would be clear if I read the relevant parts of the documentation and studied some example code. All the example code I found was too simplistic and focused on just one iteration of updating the array.
Any comments or suggestions would be much appreciated!
Looking at your playground code, I found that you are passing a blank [] array to argument of ResponseProfile struct during init. and it is always initialising your responseArray.
If you want to pass the things by reference, you can change Response profile to class
and there you can achieve the similar functionalities and use inout parameter to keep the same array without using the function updateArray.
The example I am showing here is for the class and objects of class can be pass by reference. thus keep your previous changes.
var responseTwo = ResponseProfile(responseArray:[])
If you wants to keep the old response, you can pass that array as an argument
var responseTwo = ResponseProfile(responseArray:responseOne.responseArray)
OR
var responseTwo = responseOne
Will keep the responseArray.
You can read more about it, at official blog
Also you can this post with more insight for the case.
Hope it helps.
Thanks for your response Bhavin. By passing responseArray by reference (as Bhavin suggests) to the necessary class (which has turned out to be the ButtonResponse class rather than ResponseProfile), I can give responseArray an initial value. I then use the buttonPress function to update responseArray. See below:
class ButtonResponse: Responses {
var responseArray: [String]
init (responseArray: [String]) {
self.responseArray = responseArray
}
func buttonPress(inputString: String, targetIndex: Int) -> [String] {
//need guard statement to block function when targetIndex > number of elements in responseArray
responseArray[targetIndex] = inputString
return responseArray
}
}
let initiateResponseArray =
["unchecked","unchecked","unchecked","unchecked","unchecked","unchecked","unchecked"]
var doPress = ButtonResponse(responseArray: initiateResponseArray)
doPress.buttonPress(inputString: "checked", targetIndex: 0)
var getPressInfo1 = doPress.responseArray
print(getPressInfo1)
//prints: ["checked", "unchecked", "unchecked", "unchecked", "unchecked", "unchecked", "unchecked"]
doPress.buttonPress(inputString: "checked", targetIndex: 1)
var getPressInfo2 = doPress.responseArray
print(getPressInfo2)
//prints: ["checked", "checked", "unchecked", "unchecked", "unchecked", "unchecked", "unchecked"]
I am still unsure how to implement this solution in the project I am working on. I will create a separate question for this because it seems to raise different issues.
I'm trying to convert a string into a double in swift. I managed to extract the string from a website (www.x-rates.com) into an array but I cannot convert it after in a double in order to make some work around this number. Can anyone tell me what I'm supposed to do or what I did wrong? I know that my label don't update now but I will do it later, the first thing that I'm trying to do is the conversion.
thx a lot!
Here is the code:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var resultLabel: UILabel!
#IBOutlet weak var moneyTextField: UITextField!
#IBAction func convert(_ sender: Any) {
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
let url = URL(string: "https://www.x-rates.com/calculator/?from=EUR&to=USD&amount=1")!
let request = NSMutableURLRequest(url : url)
let task = URLSession.shared.dataTask(with: request as URLRequest) {
data, response, error in
var message = ""
if let error = error {
print(error)
} else {
if let unwrappedData = data {
let dataString = NSString(data: unwrappedData, encoding: String.Encoding.utf8.rawValue)
var stringSeperator = "<span class=\"ccOutputRslt\">"
if let contentArray = dataString?.components(separatedBy: stringSeperator){
if contentArray.count > 0 {
stringSeperator = "<span"
let newContentArray = contentArray[1].components(separatedBy: stringSeperator)
if newContentArray.count > 0 {
message = newContentArray[0]
var message = Float(newContentArray[0])! + 10
}
}
}
}
}
DispatchQueue.main.sync(execute: {
self.resultLabel.text = "the value of the dollar is " + message
}
)}
task.resume()
func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
I will talk about convert an Array of String to Array of Double.
In swift Array has a method called map, this is responsable to map the value from array, example, in map function you will receive an object referent to your array, this will convert this object to your new array ex.
let arrOfStrings = ["0.3", "0.4", "0.6"];
let arrOfDoubles = arrOfStrings.map { (value) -> Double in
return Double(value)!
}
The result will be
UPDATE:
#LeoDabus comments an important tip, this example is considering an perfect datasource, but if you have a dynamic source you can put ? on return and it will work, but this will return an array with nil
like that
let arrOfStrings = ["0.3", "0.4", "0.6", "a"];
let arrOfDoubles = arrOfStrings.map { (value) -> Double? in
return Double(value)
}
Look this, the return array has a nil element
If you use the tips from #LeoDabus you will protect this case, but you need understand what do you need in your problem to choose the better option between map or compactMap
example with compactMap
let arrOfStrings = ["0.3", "0.4", "0.6", "a"];
let arrOfDoubles = arrOfStrings.compactMap { (value) -> Double? in
return Double(value)
}
look the result
UPDATE:
After talk with the author (#davidandersson) of issue, this solution with map ou contactMap isn't his problem, I did a modification in his code and work nice.
first I replaced var message = "" per var rateValue:Double = 0.0 and replacedFloattoDouble`
look the final code
let url = URL(string: "https://www.x-rates.com/calculator/?from=EUR&to=USD&amount=1")!
let request = NSMutableURLRequest(url : url)
let task = URLSession.shared.dataTask(with: request as URLRequest) {
data, response, error in
var rateValue:Double = 0.0;
if let error = error {
print(error)
} else {
if let unwrappedData = data {
let dataString = NSString(data: unwrappedData, encoding: String.Encoding.utf8.rawValue)
var stringSeperator = "<span class=\"ccOutputRslt\">"
if let contentArray = dataString?.components(separatedBy: stringSeperator){
if contentArray.count > 0 {
stringSeperator = "<span"
let newContentArray = contentArray[1].components(separatedBy: stringSeperator)
if newContentArray.count > 0 {
rateValue = Double(newContentArray[0])! + 10
}
}
}
}
}
//
print("Rate is \(rateValue)"); //Rate is 11.167
}
task.resume()
Hope to help you
The reason your code doesn’t work in my opinion is that you have two variables with the same name that are defined in different scopes and you use the wrong one at the end.
At the beginning you define
var message = ""
And then when converting to a number further down
var message = Float(newContentArray[0])! + 10
So change the last line to something like
var number = Float(newContentArray[0])! + 10
And use number in your calculations. Although I think
var number = Double(message)
should work equally fine since you have assigned newContentArray[0] to message already and Double is more commonly used than Float (I don’t understand + 10)
Hello I am trying to take an array I have and update a label to display each element in the array one second apart. An example would be me having the array [3,6,2] and my label would show 3 then wait a second and show 6 then wait a second and show 2. I've seen many NSTimer examples with update functions doing things like this but only with an incrementation on a number, never trying to parse an array. Can anyone help?
Update
I am calling my timer in a UIButton and am running into a problem. The timer works fine but my code in the button function under my timer runs before the timer and update function. My code below generates a random array of numbers then should display them one second apart. It is doing this correct but my print statement under my timer is running before it updates and displays the numbers in the textbook. I do not know why? Is the timer running on a different thread?
func updateCountdown() {
if(numbersIndex <= numberLimit){
self.counter.text = String(numbers[numbersIndex])
}else if(numbersIndex == numberLimit+1){
self.counter.text = ""
}else{
timer!.invalidate()
timer=nil
}
numbersIndex+=1
}
#IBAction func startButton(_ sender: AnyObject){
startB.setTitle("", for: .normal)
var highestLength = 3
//for trialNumber in 0...11{
var numberSequence = Array(repeating:11, count: highestLength)
for count in 0...highestLength-1{
var randomNumber = Int(arc4random_uniform(10))
if(count>0){
while(numberSequence.contains(randomNumber) || randomNumber-1 == numberSequence[count-1]){
randomNumber = Int(arc4random_uniform(10))
}
}
numberSequence[count] = randomNumber
}
print(numberSequence)
self.numbers = numberSequence
self.numbersIndex = 0
self.numberLimit = numberSequence.count-1
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(updateCountdown), userInfo: nil, repeats: true)
print("this should be last")
//do other stuff too
//}
}
you can do something like this.
var counter = 0
var list: [String] = ["Eggs", "Milk"]
override func viewDidLoad() {
super.viewDidLoad()
var timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(self.update), userInfo: nil, repeats: true)
}
func update() {
label.text = "\(list[counter])"
counter += 1
if (counter >= list.count) {
counter = 0
}
}
this is assumming the name of you Label is label