swift3.0实现图片放大缩小动画效果

一. 内容说明

跟我之前这篇类似，只不过那篇是OC版本，这篇是Swift版本 OC版本链接地址

目的：通过kingfisher请求5张图片，展示出来。然后利用图片放大缩小管理类展示图片，多张图片可以滑动浏览

效果图如下，想看动态的效果图，请看上面链接中的OC版本效果图，跟这篇是一样的。

本demo，只加载本地图片的demo下载链接 ，需要加载网络图片的，需要下载Kingfisher

二.源码展示

0. 图片测试demo源码

import Foundation
import UIKit 

class LJPhotoGroupViewController : TFBaseViewController{ 

  lazy var ljArray : [LJPhotoInfo] = [LJPhotoInfo]()
  let ljUrlArray = ["http://pica.nipic.com/2007-12-12/20071212235955316_2.jpg",
           "http://d.lanrentuku.com/down/png/1706/10avatars-material-pngs/avatars-material-man-4.png",
           "http://image.nationalgeographic.com.cn/2017/0703/20170703042329843.jpg",
           "http://image.nationalgeographic.com.cn/2015/0121/20150121033625957.jpg",
           "http://image.nationalgeographic.com.cn/2017/0702/20170702124619643.jpg"] 

  override func viewDidLoad() {
    super.viewDidLoad() 

    self.setTopNavBarTitle("图片浏览测试Demo")
    self.setTopNavBackButton()
    self.setUI()
  }
} 

extension LJPhotoGroupViewController{
  func setUI(){ 

    for index in 0...4{ 

      //1.加载本地图片
      //let image = UIImage.init(named: "\(index + 1).jpg")
      let showImageView = UIImageView.init()
      //showImageView.image = image
      showImageView.tag = index
      showImageView.frame = CGRect(x: Int((AppWidth - 200)/2.0), y: 80 + Int(90 * index), width: 200, height: 80)
      showImageView.isUserInteractionEnabled = true
      view.addSubview(showImageView) 

      //2.加载本地图片
      let url = URL(string:ljUrlArray[index])
      showImageView.kf.setImage(with: url) 

      let gestrue = UITapGestureRecognizer.init(target: self, action: #selector(LJPhotoGroupViewController.showClicked(_:)))
      showImageView.addGestureRecognizer(gestrue) 

      //需要浏览的图片添加到数组
      let info = LJPhotoInfo.init()
      info.largeImageURLStr = ljUrlArray[index]
      info.thumbImageview = showImageView
      info.currentSelectIndex = index
      self.ljArray.append(info)
    }
  }
} 

extension LJPhotoGroupViewController{ 

  func showClicked(_ sender : UITapGestureRecognizer){
    if self.ljArray.count > 0 {
      let index = sender.view?.tag
      let photoGroupView = LJPhotoGroupView.init(frame: CGRect(x: 0, y: 0, width: AppWidth, height: AppHeight))
      photoGroupView.setData(self.ljArray, selectedIndex: index!)
      photoGroupView.showPhotoView() 

      CHDebugLog("-------\(String(describing: index))")
    }
  }
}

1. LJPhotoGroupView：图片浏览管理类，用于展示图片

import Foundation
import UIKit 

class LJPhotoGroupView: UIView { 

  let baseIndex = 1000 

  var originFrame : CGRect? // 图片的源尺寸
  var currentIndex : NSInteger = 0 //当前选中的图片index
  var ljPhotoArray : [Any] = [Any]()//存储多组需要加载的图片原始信息 

  lazy var ljScrollView : UIScrollView = {
    let view = UIScrollView.init(frame: CGRect(x: 0, y: 0, width: AppWidth, height: AppHeight))
    view.delegate = self
    view.isPagingEnabled = true
    view.backgroundColor = UIColor.yellow
    return view
  }() 

  override init(frame: CGRect) {
    super.init(frame: frame)
    self.addSubview(self.ljScrollView)
  } 

  func setData(_ photoArray : Array<Any>, selectedIndex : NSInteger) {
    self.ljScrollView.contentSize = CGSize(width: floor(AppWidth) * CGFloat(photoArray.count), height: AppHeight)
    self.currentIndex = selectedIndex
    self.ljPhotoArray = photoArray
  } 

  required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }
} 

extension LJPhotoGroupView { 

// MARK: -- 图片cell复用
  func dequeueReusableCell() -> LJPhotoView { 

    var cell = self.viewWithTag(baseIndex + self.currentIndex) as? LJPhotoView 

    if ljPhotoArray.count > currentIndex {
      let info = ljPhotoArray[currentIndex] as? LJPhotoInfo
      let tempImageView = info?.thumbImageview 

      if cell != nil{
        self.originFrame = tempImageView?.convert((tempImageView?.bounds)!, to: self)
        return cell!
      } 

      cell = LJPhotoView.init(frame: CGRect(x: floor(AppWidth)*CGFloat(currentIndex), y: 0, width: AppWidth, height: AppHeight))
      self.originFrame = tempImageView?.convert((tempImageView?.bounds)!, to: self)
    }
    return cell!
  } 

// MARK: -- 展示图片
  func showPhotoView(){ 

    UIApplication.shared.keyWindow?.rootViewController?.view.addSubview(self)
    self.backgroundColor = UIColor.black 

    let cell1 = self.dequeueReusableCell()
    cell1.tag = self.baseIndex + self.currentIndex 

    var ljTempImage : UIImage?
    if ljPhotoArray.count > currentIndex {
      let info = ljPhotoArray[currentIndex] as? LJPhotoInfo
      ljTempImage = info?.thumbImageview?.image
    } 

    ljTempImage = (ljTempImage != nil) ? ljTempImage : UIImage.init(named: "pic_broadcast_gray_square") 

    let tfImageView = UIImageView.init(image: ljTempImage)
    tfImageView.frame = self.originFrame ?? CGRect.zero
    tfImageView.clipsToBounds = true
    tfImageView.backgroundColor = UIColor.red
    tfImageView.contentMode = .scaleAspectFit
    self.addSubview(tfImageView) 

    //添加页面消失的手势
    let tap = UITapGestureRecognizer.init(target: self, action: #selector(hideImageView))
    self.addGestureRecognizer(tap) 

    UIView.animate(withDuration: 0.25, animations: {
      let y : CGFloat? = (AppHeight - (ljTempImage?.size.height)! * AppWidth / (ljTempImage?.size.width)!)/2.0
      let height : CGFloat? = (ljTempImage?.size.height)! * AppWidth / (ljTempImage?.size.width)!
      tfImageView.frame = CGRect(x: 0, y: y!, width: AppWidth, height: height!)
    }) { (finish) in
      //根据选中第几张图片直接展示出来
      let cell = self.dequeueReusableCell()
      cell.tag = self.baseIndex + self.currentIndex
      cell.backgroundColor = UIColor.gray 

      if self.ljPhotoArray.count > self.currentIndex{
        cell.setCurrentImageview(self.ljPhotoArray[self.currentIndex] as! LJPhotoInfo)
      }
      let x : CGFloat = CGFloat(self.currentIndex) * floor(AppWidth);
      self.ljScrollView.setContentOffset(CGPoint.init(x: x, y: 0), animated: false)
      self.ljScrollView.addSubview(cell) 

      tfImageView.removeFromSuperview()
    }
  } 

// MARK: -- 移除图片
  func hideImageView(){
    let cell = self.viewWithTag(baseIndex + currentIndex) as? LJPhotoView
    UIView.animate(withDuration: 0.25, animations: {
      cell?.ljImageView.frame = self.originFrame!
    }) { (finish) in
      self.backgroundColor = UIColor.white
      self.removeFromSuperview()
    }
  }
} 

extension LJPhotoGroupView : UIScrollViewDelegate{ 

  func scrollViewDidScroll(_ scrollView: UIScrollView) {
    //滑动时，会调用多次
  } 

  func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
   //滑动完毕时，只会调用一次
    let page = self.ljScrollView.contentOffset.x / self.frame.size.width;
    self.currentIndex = NSInteger(page);
    print("scrollViewDidEndDecelerating当前页数----\(page)") 

    let cell = self.dequeueReusableCell()
    cell.tag = self.baseIndex + Int(page)
    if self.ljPhotoArray.count > self.currentIndex{
      cell.setCurrentImageview(self.ljPhotoArray[self.currentIndex] as! LJPhotoInfo)
    }
    self.ljScrollView.addSubview(cell)
  }
}

2. LJPhotoInfo：图片信息的model

import Foundation
import UIKit 

class LJPhotoInfo: NSObject { 

  var currentSelectIndex : Int?
  var largeImageURLStr : String?
  var thumbImageview : UIImageView? 

  override init() {
    super.init()
  }
}

3.LJPhotoView：图片浏览管理类用到的cell（图片显示）

import Foundation
import UIKit 

class LJPhotoView: UIScrollView { 

  var ljInfo : LJPhotoInfo? 

  lazy var ljImageView : UIImageView = {
      let view = UIImageView()
      view.clipsToBounds = true
      view.contentMode = .scaleAspectFit
      return view
    }() 

  override init(frame: CGRect) {
    super.init(frame: frame)
    self.zoomScale = 1.0
    self.addSubview(self.ljImageView)
  } 

  required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }
} 

extension LJPhotoView{
  func setCurrentImageview(_ info : LJPhotoInfo){
    self.ljInfo = info
    if self.ljInfo?.thumbImageview?.image == nil{
      self.ljInfo?.thumbImageview?.image = UIImage.init(named: "pic_broadcast_gray_square")
    } 

    //无url，则通过thumbImageview获取Image展示
    //self.ljImageview.image = info.thumbImageview.image;
    let y : CGFloat? = (AppHeight - (info.thumbImageview?.image?.size.height)! * AppWidth / (info.thumbImageview?.image?.size.width)!) * 0.5;
    self.ljImageView.frame = CGRect(x: 0, y: y!, width: AppWidth, height: AppWidth*(info.thumbImageview?.image?.size.height)!/(info.thumbImageview?.image?.size.width)!)
    self.ljImageView.image = self.ljInfo?.thumbImageview?.image 

    if info.largeImageURLStr != "" {
      let url = URL(string:info.largeImageURLStr!)
      self.ljImageView.kf.setImage(with: url)
    }
  }
}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。