I am a beginner and I am building a RPN calculator. I have disabled the point key (not clickable anymore) if the digit situated in the display has already a point. How can I enable it again after having pressed the enter key? Because now, it stays disabled even if I enter another digit in the display. So if I clicked on the point key once for the first digit, I cannot add a point for the second digit of my operation.
I have that code for to add a point to a digit:
#IBAction func floatingPoint(sender: UIButton) {
labelDisplay.text = labelDisplay.text! + "."
sender.enabled = false //not clickable if the digit as already a point
}
I have that code for enter:
var enterPressed = false
#IBAction func Enter() {
userHasStartedTyping = false
self.calcEngine!.operandStack.append(displayValue)
print("Operand Stack on engine = \(self.calcEngine!.operandStack)")
}
I have that code for the operation:
#IBAction func operation(sender: UIButton) {
let operation = sender.currentTitle!
if userHasStartedTyping {
Enter()
}
self.displayValue = (self.calcEngine?.operate(operation))!
Enter() //
}
You will have to add an #IBOutlet in your class, so you can access this button from various parts of your code, not just it's action method. For example, add this to the top of your view controller:
#IBOutlet var pointButton:UIButton!
Remember to connect the button to this outlet on your storyboard.
With that, you can re-enable the point button in your Enter() method for example. Like this:
pointButton:UIButton.enabled = true
Related
I am learning Swift, and I am throwing myself in the deep end to force myself to learn the language. I have a nephew who is a baby and thought to make an app to help him learn numbers.
The app is designed to set a set number of buttons on the screen like the one provided below. I have the code to play Directions, which tells the user which number to select. A-N14a, the audio file, says to click the 4. The Done button is set to move to the next screen.
What I am asking is that if I want 4 to be pressed, and they press the 9, I want to know how to implement a feature to give a hint to click the number 4? The idea is to change the background to a button, but I don't know how to implement the feature. I am also open to other ideas. As a note, I do not know what to do, and I'm trying to learn, so the code provided is probably very simplistic and is at the beginning stages.
Below is an image of the screen and the code for that page.
ScreenShot of Page
import UIKit
import AVFoundation
class Intervention_Numerals1: UIViewController {
#IBOutlet weak var Directions: UIButton!
#IBOutlet weak var Done: UIButton!
var audioPlayer = AVAudioPlayer()
override func viewDidLoad() {
super.viewDidLoad()
setUpElements()
//Audio Test
do {
audioPlayer = try AVAudioPlayer(contentsOf: URL.init(fileURLWithPath: Bundle.main.path(forResource: "A-N14a", ofType:"mp3")!))
audioPlayer.prepareToPlay()
} catch {
print(error)
}
}
func setUpElements() {
// Style the elements
Utilities.styleFilledButton(Directions)
Utilities.styleFilledButton(Done)
}
#IBAction func Play(_ sender: Any) {
audioPlayer.play()
}
}
Please let me know any tips or advice or links to similar questions, even though I could not find any on my own.
Here's what I would do:
Record the sound "Tap the number" and then the sounds for the numbers 0 through 9. Name the number sounds "0.mp3" through "9.mp3"
Create a storyboard with 4 buttons on it (like the picture you posted.)
Set up button IBOutlets buttonA - buttonD. Put those buttons into an array:
let buttonsArray = [buttonA, buttonB, buttonC, buttonD]
Fill an array with the numbers 0-9. Shuffle it. Remove 4 values put them into an array "buttonValues" (use the method removeLast().) The code to generate non-repeating values from 0-9 might look like this:
var randomNumbers = [Int]() //Define an array to hold random Ints
var lastValueReturned: Int?
//Function to return a random Int. It won't return the same value twice
func randomNumber() -> Int {
//Remove and return an item from the array
var result: Int
repeat {
//If the array is empty, fill it with the shuffled numbers 0...9
if randomNumbers.isEmpty {
randomNumbers += Array(0...9).shuffled()
}
result = randomNumbers.removeLast()
} while result == lastValueReturned
lastValueReturned = result
return result
}
Loop through your array of buttonValues and install the string for each number as the title of one of your buttons:
for index = 0...3 {
buttonsArray[index].setTitle("(buttonValues[index])", forSate: .normal)
}
Pick an index 0-3 to be the "correct" number.
let indexToPick = Int.random(in: 0...3)
Look up that value in buttonValues, and use it to pick a sound file to play:
let numberToPick = buttonValues[indexToPick]
let soundName = "\(numberToPick).mp3"
Load and play the "tap the number" sound, and then Load and play the sound for the selected number (soundName).
When the user taps a button, have the IBAction method use the sender parameter that is passed to it, and look in the array of buttons, buttonsArray, to see which button index was tapped.
If it is the correct button, take the success action.
If the tapped button index is not indexToPick, do an animation that changes the background color of the button at indexToPick, or the button's border width, or something, and then animates it back to normal. (Look at the UIView animate(duration:) family of methods for how to animate the button's background color. Use the form that takes an options: parameter, and set the .autoreverse option.)
If you're a newbie to iOS development, figuring out how to animate your correct answer button could be a challenge. I created a sample project that just animates one of 4 random buttons: https://github.com/DuncanMC/ButtonAnimation.git
The code for that project is as follows:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var buttonA: UIButton!
#IBOutlet weak var buttonB: UIButton!
#IBOutlet weak var buttonC: UIButton!
#IBOutlet weak var buttonD: UIButton!
//Define an empty array to hold buttons.
var buttonsArray = [UIButton]()
override func viewDidLoad() {
super.viewDidLoad()
//Put our button outlets into an array so we can reference them by index.
buttonsArray = [buttonA, buttonB, buttonC, buttonD]
//Give our buttons a cornerRadius so they look rounded when we add a border and fill color
for button in buttonsArray {
button.layer.cornerRadius = 10
}
}
#IBAction func handleAnimateButton(_ sender: UIButton) {
sender.isEnabled = false
//Pick a random button
let button = buttonsArray.randomElement()!
//Create an auto-reversing animation that fills the button with cyan, and draws a border around it.
//(Showing the border won't fade in and out, but it doesn't really matter)
UIView.animate(withDuration: 0.25,
delay: 0,
options: [.autoreverse, .curveEaseInOut],
animations: {
button.backgroundColor = .cyan
button.layer.borderWidth = 1.0
}, completion: {
success in
button.backgroundColor = .clear
sender.isEnabled = true
button.layer.borderWidth = 0
})
}
}
I would do as follows:
1. Create as many IBOutlets as your numbers (I suppose 0-9 for your example?) and link them to your buttons - E.g.
#IBOutlet weak var Button1: UIButton!
#IBOutlet weak var Button2: UIButton!
// Create as many as you need - Probably 10?
2. Create an IBAction and link it to all your buttons, with this code
#IBAction func checkCorrectAnswer(_ sender: UIButton) {
let arrayOfButtons:[UIButton] = [Button1, Button2] // Here you add all your buttons
let buttonTitle = sender.title(for: .normal)!
if buttonTitle == "YOUR CORRECT ANSWER" { //You have to substitute "YOUR CORRECT ANSWER" with the right string value
sender.backgroundColor = .green
} else {
sender.backgroundColor = .red
for i in arrayOfButtons {
if i.titleLabel?.text == "YOUR CORRECT ANSWER" { i.backgroundColor = .orange }
}
}
}
Enjoy!
I am trying to change the text of a UILabel in my code, but the text won't change.
I tried to use the well-known command for changing the text, "NameOfLabel.text = 'Hello", but that did not work. So I tried to put it in a start function so you would click a UIButton and it would change the text, didn't work either.
#IBOutlet var nameOfRobot: UILabel!
#IBAction func startButton(_ sender: Any){
let nameNumber = Int.random(in: 1...3)
if nameNumber == 1 {
self.nameOfRobot.text = "Ben"
}
if nameNumber == 2 {
self.nameOfRobot.text = "Oliver"
}
if nameNumber == 3 {
self.nameOfRobot.text = "Colton"
}
}
I want it to choose a number between 1 and three and have it change the UILabel to that name. When I start the app though, it works, but it doesn't change the text of the label.
Looks like you forgot to connect the action to the button press:
You can tell this is done correctly by looking at the full circle indicator in the editor:
EDIT: Setting the correct class to the viewController in the storyboard:
I have a button with a long-press gesture recognizer assigned to it.
I would like the button to remain highlighted (just as it would during a normal click) for the duration of a long press, AND for the single click NOT to be triggered after the long press.
What I have tried so far:
To illustrate why it might be important to have this functionality, let's take the example of a UILabel that displays a number, and a button that increments that number.
A single click should increment the number by 1, and a long-press should increment it by 10 (a timer could be added later that "auto-increments" the number as the finger is held down, but for the purposes of this example, I am leaving that out).
So I started with this code:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var numberDisplayLabel: UILabel!
#IBOutlet weak var incrementNumberButton: UIButton!
#IBOutlet var buttonLPGR: UILongPressGestureRecognizer!
var numVal = 0
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
numberDisplayLabel.text = String(numVal)
}
#IBAction func buttonClicked(_ sender: UIButton) {
print("button clicked")
numVal += 1
numberDisplayLabel.text = String(numVal)
}
#IBAction func longPressOnButtonRecognized(_ sender: UILongPressGestureRecognizer) {
print("long press recognized, state: \(sender.state.rawValue)")
if (sender.state == .ended) {
numVal += 10
numberDisplayLabel.text = String(numVal)
}
}
}
Let's try to single click and see if that works:
Yes it does, YAY.
Now let's see what happens if we long-press it:
So... you can see that the button highlights when touched down (as normal), but when the long press is recognized (enters the .began state), the highlight is cancelled. When we finally release the touch, the number is incremented by 10 as expected.
But what if we want the button to remain highlighted during the entire process...
we could try adding this code to viewDidLoad():
buttonLPGR.cancelsTouchesInView = false
This should prevent the initial touch from being cancelled by the long-press recognition.
Let's see! :
Hmmm well we got what we wanted as far as the highlighting, but now, since the regular press is no longer cancelled by the long press, the button's touchUpInside action function is still called and so the number is incremented not only by 10, but by 1 also.
This is where I don't know what to do from this point.
So, once again: How can we have the button remain highlighted (just as it would during a normal click) for the duration of a long press, AND for the single click NOT to be triggered after the long press?
If the touch framework provides a way of doing this without a work-around, that would be preferred.
I have an app where a user can select a number of different buttons onscreen. When a user selects a button, it turns green and the text will be used in a later view. I am trying to make everything nice and swift by minimising the amount of code I am writing.
Every button is connected to the same action and their identity is determined by their tag. What I have done is created 2 arrays to track the card name and their on/off state. When a card is pressed the cardPressed function is called, this decides whether to turn the card green or white currently (it will do more later).
What I want to do is to perform the colour change in one line of code, instead of
cardOne.backgroundColor = UIColor.white
I want to do this [#1]
cardList[cardNumber].backgroundColor = UIColor.green
so that my outlet changes depending on the selection made. I would normally just have a massive switch statement that would read like so
switch cardList[cardNumber] {
case 0:
cardOne.backgroundColor = UIColor.green
case 1:
cardTwo.backgroundColor = UIColor.green
case 2:
cardThree.backgroundColor = UIColor.green
case So on so forth:
cardInfinity.......
default:
break
}
Obviously when I try to do [#1] I get an error because it is a string, not an outlet connection. What I would like to know, is there anyway to trick xcode into recognising it as an outlet, or better yet have a way to change the outlets I am acting upon in one line of code?
Hopefully I haven't rambled too much and you can understand my thought process! I have included all of the relevant code below, obviously it won't compile. If you have any ideas they would be appreciated, or if I'm being too optimistic and this isnt possible, just let me know :) for now I will be using a big switch statement! (maybe this is useful to me in the future!)
Thanks!
private let cardList = ["cardOne","cardTwo","cardThree"]
private var cardState = [false, false, false]
//Card functions
private func selectCard(cardNumber: Int){
cardState[cardNumber] = true
cardList[cardNumber].backgroundColor = UIColor.green
}
private func deselectCard(cardNumber: Int){
cardState[cardNumber] = false
//cardOne.backgroundColor = UIColor.white
}
//Decide which function to perform, based on the card information recieved
private func cardPressed(cardNumber: Int){
let selectedCardName = cardList[cardNumber]
let selectedCardState = cardState[cardNumber]
print("\(selectedCardName)")
print("\(selectedCardState)")
switch selectedCardState {
case true:
deselectCard(cardNumber: cardNumber)
case false:
selectCard(cardNumber: cardNumber)
}
}
//UI Connections
//Card button actions
#IBAction func buttonPressed(_ sender: UIButton) {
//Determine which button has been pressed
//let cardName = sender.currentTitle!
let cardSelection = sender.tag - 1
cardPressed(cardNumber: cardSelection)
}
//Card button outlets
#IBOutlet weak var cardOne: UIButton!
#IBOutlet weak var cardTwo: UIButton!
The solution lies in the wonderful world of object-oriented programming. Instead of using parallel arrays, you can create your own data type to group this data and behavior together.
If you created your own UIButton subclass, you could keep track of whether the button is selected with your own custom property, and make visual modifications as needed.
class CardButton: UIButton {
var isChosen: Bool = false {
didSet { backgroundColor = isChosen ? UIColor.green : UIColor.white }
}
}
If you set the buttons in the storyboard to be your new CardButton type, you can use their isChosen property in code.
Your buttonPressed function could look like this instead:
#IBAction func buttonPressed(_ sender: CardButton) {
sender.isChosen = !sender.isChosen
}
This would allow you to remove the majority of your existing code, since the data is stored inside each of your buttons.
I have a function to hide a slider if another button is pressed. I currently have:
#IBOutlet weak var sliderHide: UISlider!
#IBAction func sliderHide(sender: UISlider) {
if (buttonPlay.selected) {
sliderHide.hidden = false
}
else if (!buttonPlay.selected) {
sliderHide.hidden = true
}
}
The build is running but the slider only hides if itself is selected. It does nothing if the button is selected.
Use == not = when comparing,= is an assignment operator.
Moreover, if buttonImage is not a variable representing the control state of a button, but the button itself you want to do:
if buttonImage.selected == false {
}
However, you should use an #IBAction for the button if you want to run a function when it is pressed.
Please consider using an #IBAction for this kind of thing unless your button is programmatically created. You can read more about it here:
http://rshankar.com/different-ways-to-connect-ibaction-to-uibutton/
I
I think you want
add an Outlet to the slider like the picture and then wherever you play the sound, make the sliderYouMightHide.hidden = false and wherever the sound stops make the sliderYouMightHide.hidden = true. You might also want to make it hidden in viewDidLoad