当第一个 ScrollView 滚动时滚动第二个 Scrollview答案

【问题标题】：Scroll second Scrollview when first ScrollView did scroll当第一个 ScrollView 滚动时滚动第二个 Scrollview
【发布时间】：2017-12-01 17:03:14
【问题描述】：

我的项目中有两个ScrollViews，它们应该同时滚动。当我滚动myFriendsScrollView 时它应该可以工作。

这是我未完成的代码：

import Foundation
import UIKit

class profileController: UIViewController {

@IBOutlet weak var myFriendsScrollView: UIScrollView!
@IBOutlet weak var myFriendsNameScrollView: UIScrollView!

override func viewDidLoad() {
    super.viewDidLoad()

    // My Scrollview One
    let myFriendsScrollViewHeight = self.myFriendsScrollView.frame.height
    let myFriendsScrollViewWidth = self.myFriendsScrollView.frame.width

    let myFriendImg1 = UIImageView(frame: CGRect(x: 0, y: 0, width: myFriendsScrollViewWidth/4, height: myFriendsScrollViewHeight))
    let myFriendImg2 = UIImageView(frame: CGRect(x: 100 , y: 0, width: myFriendsScrollViewWidth/4, height: myFriendsScrollViewHeight))  
    let myFriendImg3 = UIImageView(frame: CGRect(x: 200 , y: 0, width: myFriendsScrollViewWidth/4, height: myFriendsScrollViewHeight))

    self.myFriendsScrollView.addSubview(myFriendImg1)
    self.myFriendsScrollView.addSubview(myFriendImg2)
    self.myFriendsScrollView.addSubview(myFriendImg3)

    myFriendImg1.image = UIImage(named: "avatar_placeholder");
    myFriendImg2.image = UIImage(named: "avatar_placeholder");
    myFriendImg3.image = UIImage(named: "avatar_placeholder");


    self.myFriendsScrollView.contentSize = CGSize(width: self.myFriendsScrollView.frame.width*2, height: self.myFriendsScrollView.frame.height)
    self.myFriendsScrollView.isPagingEnabled = true

    // My Scrollview Two
    let myFriendsNameScrollViewHeight = self.myFriendsNameScrollView.frame.height
    let myFriendsNameScrollViewWidth = self.myFriendsNameScrollView.frame.width

    let myFriendLbl1 = UILabel(frame: CGRect(x: 0, y: 0, width: myFriendsNameScrollViewWidth/4, height: myFriendsNameScrollViewHeight))
    let myFriendLbl2 = UILabel(frame: CGRect(x: 100 , y: 0, width: myFriendsNameScrollViewWidth/4, height: myFriendsNameScrollViewHeight))
    let myFriendLbl3 = UILabel(frame: CGRect(x: 200 , y: 0, width: myFriendsNameScrollViewWidth/4, height: myFriendsNameScrollViewHeight))

    self.myFriendsNameScrollView.addSubview(myFriendLbl1)
    self.myFriendsNameScrollView.addSubview(myFriendLbl2)
    self.myFriendsNameScrollView.addSubview(myFriendLbl3)

    myFriendLbl1.text = "UserName";
    myFriendLbl2.text = "UserName";
    myFriendLbl3.text = "UserName";

    self.myFriendsNameScrollView.contentSize = CGSize(width: self.myFriendsNameScrollView.frame.width*2, height: self.myFriendsNameScrollView.frame.height)
    self.myFriendsNameScrollView.isPagingEnabled = true

}  

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    if scrollView == myFriendsScrollView {
        myFriendsNameScrollView.contentOffset = scrollView.contentOffset
    }
    else {
        myFriendsScrollView.contentOffset = scrollView.contentOffset
    }
}

}

感谢您的帮助。

【问题讨论】：

我认为这可以帮助你:- stackoverflow.com/questions/41131986/…
尝试用主线程包围，.....看下面的答案，在主线程中做你的UI操作

标签： ios swift function swift3 uiscrollview

【解决方案1】：

你可以使用它的委托方法。并在其他 ScrollView 上设置内容 OffSet

  func scrollViewDidScroll(_ scrollView: UIScrollView!) {
            // This will be called every time the user scrolls the scroll view 

       if  myFriendsScrollView ==scrollView 
        {
           let contentOffSet = scrollView.contentOffset

         //change the Off set of other ScrollView   
     // just surround with main thread 

      DispatchQueue.main.async {
         secondScrollView.setContentOffset=contentOffSet;
       }
    }



  }

希望对你有帮助

【讨论】：

【解决方案2】：

您的委托方法的实现似乎已经正确，我已经在操场上进行了测试，它似乎工作得很好。

但是，它看起来并没有真正连接起来。确保您的班级是：

class profileController: UIViewController, UIScrollViewDelegate { ... }

并添加viewDidLoad:

myFriendsScrollView.delegate = self
myFriendsNameScrollView.delegate = self

【讨论】：