UIImageView 的延迟时间

Posted 2023-02-23

【中文标题】UIImageView 的延迟时间

【英文标题】：delay time on UIImageView

【发布时间】：2016-07-21 09:12:39

【问题描述】：

当我将图像索引从 collectionView 发送到另一个 viewController 时，我有图像数组，该 viewController 全屏显示此图像，并且我让用户能够在图像之间滑动，但滑动时出现问题 更改时图像之间的滑动非常快我需要在更改图像时延迟 UIImageView 上的时间关于该问题的任何解决方案？

下面的代码：

var ImageIndex:Int = 0 // this is index image which i send it from previous view controller
var arrayOfUrlImageLarge:[String] = []// this array which contain all the url of images

覆盖 func viewDidLoad()

    super.viewDidLoad()

imageView = UIImageView(image: UIImage(contentsOfFile: arrayOfUrlImageLarge[ImageIndex]))

    imageView.contentMode = UIViewContentMode.ScaleAspectFill

     let swipeGestureRight = UISwipeGestureRecognizer(target: self, action: #selector(ShowImageViewController.swipe(_:)))
    swipeGestureRight.direction = .Right
    let swipeGestureLeft = UISwipeGestureRecognizer(target: self, action: #selector(ShowImageViewController.swipe(_:)))
    swipeGestureLeft.direction = .Left
    self.imageView.addGestureRecognizer(swipeGestureLeft)
    self.imageView.addGestureRecognizer(swipeGestureRight)
 

func swipe(gesture:UISwipeGestureRecognizer)

    if gesture.direction == .Right 

        if ImageIndex == 0 
            imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
        else 
            ImageIndex = ImageIndex - 1
            imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
        
    
    if gesture.direction == .Left

        if ImageIndex >= arrayOfUrlImageLarge.count 
            ImageIndex = arrayOfUrlImageLarge.count - 1
            imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
        else 
            ImageIndex = ImageIndex + 1
            if ImageIndex >= arrayOfUrlImageLarge.count 
                return
            
            imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)

        
    

谢谢

【参考方案1】：

func swipe(gesture:UISwipeGestureRecognizer)

   let delay = 4.5 * Double(NSEC_PER_SEC)
   let time = dispatch_time(DISPATCH_TIME_NOW, Int64(delay))
   dispatch_after(time, dispatch_get_main_queue()) 

       if gesture.direction == .Right 

        if ImageIndex == 0 
           imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
        
        else 
          ImageIndex = ImageIndex - 1
          imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
        
       
      if gesture.direction == .Left

        if ImageIndex >= arrayOfUrlImageLarge.count 
           ImageIndex = arrayOfUrlImageLarge.count - 1
           imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
       
       else 
         ImageIndex = ImageIndex + 1
         if ImageIndex >= arrayOfUrlImageLarge.count 
            return
         
        imageView.image = UIImage(data: NSData(contentsOfFile: arrayOfUrlImageLarge[ImageIndex])!)
        

      
   

【讨论】：

非常感谢我把这个方法放在 viewdidload 的什么地方？

用同样的方法试试

检查持续时间后它将执行的更新答案

在评论动画里在做什么？褪色？

你不需要任何动画。