问题
I am a newbie swift programmer, and I have been asked to write an app that allows you to type in a word, and then generates a random Haiku This is a tabbed application, with two ViewControllers. (poem) based on that word. So in the FirstViewController I have the data, and I want to display that data in a nice way, in the SecondViewController. I have all the poem lines and all in the FirstViewController, but I would like to access these variables in the SecondViewController. I have tried creating a function, that does nothing but returning them, and then in the SecondViewController calling that function, but without any result, since the function simply returned nil. Would be pleased if any of you could help Thank you!
Here is the FirstViewController:
import UIKit
import Foundation
class FirstViewController: UIViewController, UITextFieldDelegate {
@IBOutlet weak var keyWordTextField: UITextField!
@IBOutlet weak var syllableSlider: UISlider!
@IBOutlet weak var syllableSliderLabel: UILabel!
var syllableSliderValue = 1
@IBOutlet weak var lineOneTextField: UITextField!
@IBOutlet weak var lineTwoTextField: UITextField!
@IBOutlet weak var lineThreeTextField: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
lineOneTextField.text = "Rad 1"
lineTwoTextField.text = "Rad 2"
lineThreeTextField.text = "Rad 3"
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func syllableValueChanged(sender: UISlider) {
syllableSliderValue = Int((sender.value))
syllableSliderLabel.text = "Ordet har: \(syllableSliderValue) stavelser"
}
@IBAction func getNewHaiku() {
if keyWordTextField.text != "" {
let keyWord = keyWordTextField.text
let lineOne = generateLine(keyWord: keyWord, syllables: syllableSliderValue, lineSyllableLenght: 5)
let lineTwo = generateLine(keyWord: keyWord, syllables: syllableSliderValue, lineSyllableLenght: 7)
let lineThree = generateLine(keyWord: keyWord, syllables: syllableSliderValue, lineSyllableLenght: 5)
lineOneTextField.text! = lineOne
lineTwoTextField.text! = lineTwo
lineThreeTextField.text! = lineThree
}
}
func generateLine(#keyWord: String, syllables : Int, lineSyllableLenght : Int) -> String {
let oneSyllables = Dict().oneSyllables
let twoSyllables = Dict().twoSyllables
let threeSyllables = Dict().threeSyllables
let fourSyllables = Dict().fourSyllables
let randomOneSyllableWordNumber = Int(arc4random_uniform(UInt32(oneSyllables.count)))
let randomTwoSyllableWordNumber = Int(arc4random_uniform(UInt32(twoSyllables.count)))
let randomThreeSyllableWordNumber = Int(arc4random_uniform(UInt32(threeSyllables.count)))
let randomFourSyllableWordNumber = Int(arc4random_uniform(UInt32(fourSyllables.count)))
var lineArray : [String] = []
var line = ""
lineArray.append(keyWord)
if syllables == 1 {
let randomWordMethod = Int(arc4random_uniform(2))
if randomWordMethod == 0 {
lineArray.append(fourSyllables[randomFourSyllableWordNumber])
} else if randomWordMethod == 1 {
lineArray.append(threeSyllables[randomThreeSyllableWordNumber])
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
} else if randomWordMethod == 2 {
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
lineArray.append(twoSyllables[randomOneSyllableWordNumber])
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
}
} else if syllables == 2 {
let randomWordMethod = Int(arc4random_uniform(2))
if randomWordMethod == 0 {
lineArray.append(twoSyllables[randomOneSyllableWordNumber])
lineArray.append(oneSyllables[randomTwoSyllableWordNumber])
} else if randomWordMethod == 1 {
lineArray.append(threeSyllables[randomThreeSyllableWordNumber])
} else if randomWordMethod == 2 {
lineArray.append(twoSyllables[randomTwoSyllableWordNumber])
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
}
} else if syllables == 3 {
let randomWordMethod = Int(arc4random_uniform(1))
if randomWordMethod == 0 {
lineArray.append(twoSyllables[randomTwoSyllableWordNumber])
} else if randomWordMethod == 1 {
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
}
} else if syllables == 4 {
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
}
if lineSyllableLenght == 7 {
let randomWordMethod = Int(arc4random_uniform(1))
if randomWordMethod == 0 {
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
lineArray.append(oneSyllables[randomOneSyllableWordNumber])
} else if randomWordMethod == 1 {
lineArray.append(twoSyllables[randomTwoSyllableWordNumber])
}
}
for word in lineArray {
line += " \(word)"
}
line += ","
return line
}
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
self.view.endEditing(true)
}
func getData() -> (line2: String, line3: String) {
return (lineTwoTextField.text, lineThreeTextField.text)
}
}
Ps, the "Dict" is another file, but only containing words.
The second view controller is just blank.
回答1:
You need to pass the instances like this in second view controller:
var firstViewController: FirstViewController?
Then in the master instance which knows both:
secondViewController.firstViewController = firstViewController
(e.g. in awakeFromNib) assuming that they are known in the master instance like
let firstViewController = FirstViewController()
let secondViewController = SecondViewController()
Finally in SecondViewController you can access the first:
firstViewController?.generateLine....
回答2:
Or you could make it a global variable so any file can access it.
struct structname {
static var yourvariable = value
}
When calling it, you enter
filename.structname.yourvariable
来源：https://stackoverflow.com/questions/28002847/swift-accessing-variable-from-another-file