Question

我正在构建一个flashcard应用程序。我在下面附上了我的代码。当下面的代码运行时，用户应该能够向左和向右滑动一系列卡片（每张卡片包含一个与声音相结合的图像。有两个名为firstList和secondList的卡片阵列）。轻触图像时，应该播放与之耦合的声音。我没有在播放声音或刷一个列表时遇到问题。但是，当我尝试组合并滑动“firstList”和“secondList”时，我收到错误。我似乎无法弄清楚的一个错误是“没有更多上下文的表达类型是模棱两可的”。请参阅下面的代码和错误

import UIKit

class SecondViewController: UIViewController , UIGestureRecognizerDelegate  {

var imageIndex: Int = 0
@IBAction func home(_ sender: Any) {
    performSegue(withIdentifier: "home", sender: self)
}

@IBOutlet weak var imgPhoto: UIImageView!

struct List {
    let words: [Card] /*Create array of cards*/
    var active: Bool
}



let firstList:[Card] = [
    Card(image: UIImage(named: "lake")!, soundUrl: "lake"),
    Card(image: UIImage(named: "river")!, soundUrl: "river"),
    Card(image: UIImage(named: "ocean")!, soundUrl: "ocean")
]

let secondList:[Card] = [
    Card(image: UIImage(named: "alligator")!, soundUrl: "alligator"),
    Card(image: UIImage(named: "apple")!, soundUrl: "apple"),
    Card(image: UIImage(named: "grape")!, soundUrl: "grape")
]

override func viewDidLoad() {


    var imageList: [String] {
        let list1 = List(words:firstList, active: true)
        let list2 = List(words:secondList, active: true)

        let wordLists = [list1, list2]

        let active = wordLists.reduce([]) { (result:[String], list:List) in
            if list.active {
                return result + list.words

            } else {
                return result
            }
        }

        return active

    }

    super.viewDidLoad()

    let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(imageTapped(tapGestureRecognizer:)))
    imgPhoto.isUserInteractionEnabled = true
    imgPhoto.addGestureRecognizer(tapGestureRecognizer)


    imgPhoto.image = (wordLists)[0]; ).image

    // Do any additional setup after loading the view.
    imgPhoto.isUserInteractionEnabled = true

    let leftSwipe = UISwipeGestureRecognizer(target: self, action: #selector(Swiped(gesture:)))
    leftSwipe.cancelsTouchesInView = false

    let rightSwipe = UISwipeGestureRecognizer(target: self, action: #selector(Swiped(gesture:)))
    rightSwipe.cancelsTouchesInView = false

    leftSwipe.direction = .left
    rightSwipe.direction = .right

    view.addGestureRecognizer(leftSwipe)
    view.addGestureRecognizer(rightSwipe)

}


func imageTapped(tapGestureRecognizer: UITapGestureRecognizer)
{

    itemList[imageIndex].playSound()
    // Your action
}
func Swiped(gesture: UIGestureRecognizer) {

    if let swipeGesture = gesture as? UISwipeGestureRecognizer {

        switch swipeGesture.direction {

        case UISwipeGestureRecognizerDirection.right :
            print("User swiped right")

            // decrease index first

            imageIndex -= 1

            // check if index is in range

            if imageIndex < 0 {

                imageIndex = itemList.count - 1

            }

            imgPhoto.image = itemList[imageIndex].image

        case UISwipeGestureRecognizerDirection.left:
            print("User swiped Left")

            // increase index first

            imageIndex += 1

            // check if index is in range

            if imageIndex > itemList.count - 1 {

                imageIndex = 0

            }

            imgPhoto.image = itemList[imageIndex].image
        default:


            break //stops the code/codes nothing.
        }
    }
}
}

包含每张“Card”信息的类位于

之下

import Foundation; import UIKit; import AVFoundation

var player: AVAudioPlayer?

class Card: NSObject
{
var image: UIImage
var soundUrl: String


init(image: UIImage, soundUrl: String) {
    self.image = image
    self.soundUrl = soundUrl
}
 func playSound()

{ print("play")
    guard let url = Bundle.main.url(forResource: self.soundUrl, withExtension: "m4a") else { return }
    do
    {
        try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
        try AVAudioSession.sharedInstance().setActive(true)

        player = try AVAudioPlayer(contentsOf: url)
        guard let player = player else { return }
        player.prepareToPlay()
        player.play()
    print("hhh")
    } catch let error {
        print(error.localizedDescription)
    }
}
}

Answer 1

第一个问题：

result + list.words

result是[String]，list.words是[Card]。你想用这条线做什么？

第二个问题：

imgPhoto.image = (wordLists)[0]; ).image

wordLists是[List]，每个[Card]都包含words作为属性imgPhoto.image = wordLists[0].words[0].image

看起来你正试图从其中一张卡片中的一张卡片中抓取一张图片，但不清楚你要抓的是哪张卡片。从第一个列表中抓取第一张卡片中的图像的示例如下：

itemList

第三个问题：

您尝试引用一个似乎不存在的名为var pcapp = require('pcap-parser'); var parser = pcapp.parse('C:/Users/.../data.pcap'); parser.on('packet', function(packet) { console.log(packet); });的变量。它未在您列出的代码中的任何位置声明，但我怀疑它是针对该类的属性。

组合多个数组。调试xcode swift

1 个答案: