如何使 ScrollView 中的 TableView 的滚动表现自然

我需要做一个配置奇怪的应用程序。

如下图所示,主视图是一个 UIScrollView。然后在它里面应该有一个 UIPageView,并且 PageView 的每个页面都应该有一个 UITableView。

figure

到目前为止,我已经做了所有这些。但是我的问题是,我想要滚动到 规矩点 很自然

接下来就是我所说的 很自然。当前,当我在一个 UITableViews 上滚动时,它会滚动 tableview (而不是 scrollview)。但是我希望它能够滚动 ScrollView,除非 ScrollView 无法滚动,因为它已经到了它的顶部或底部(在这种情况下,我希望它能够滚动表格视图)。

例如,假设我的 scrollview 当前滚动到顶部。然后我把手指放在当前页面的表格视图上,开始滚动 放下。在这种情况下,我希望 scrollview 滚动(不是 tableview)。如果我继续向下滚动滚动视图,它会到达底部,如果我把手指从显示屏上移开,把它放回视图上,再向下滚动,我希望我的视图现在向下滚动,因为滚动视图已经到达底部,它不能继续滚动。

你们知道如何实现这个滚动吗?

我真的迷路了。任何帮助都将非常感激:

谢谢!

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I think there are two options.

Since you know the size of the scroll view and the main view, you are unable to tell whether the scroll view hit the bottom or not.

if (scrollView.contentOffset.y >= (scrollView.contentSize.height - scrollView.frame.size.height)) {
// reach bottom
}

So when it hit; you basically set

[contentScrollView setScrollEnabled:NO];

and other way around for your tableView.

The other thing, which is more precise I think, is to add Gesture to your views.

UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc]
initWithTarget:self action:@selector(respondToTapGesture:)];


// Specify that the gesture must be a single tap
tapRecognizer.numberOfTapsRequired = 1;


// Add the tap gesture recognizer to the view
[self.view addGestureRecognizer:tapRecognizer];


// Do any additional setup after loading the view, typically from a nib

So when you add Gesture, you can simply control the active view by changing setScrollEnabled in the respondToTapGesture.

The solution to simultaneously handling the scroll view and the table view revolves around the UIScrollViewDelegate. Therefore, have your view controller conform to that protocol:

class ViewController: UIViewController, UIScrollViewDelegate {

I’ll represent the scroll view and table view as outlets:

@IBOutlet weak var scrollView: UIScrollView!
@IBOutlet weak var tableView: UITableView!

We’ll also need to track the height of the scroll view content as well as the screen height. You’ll see why later.

let screenHeight = UIScreen.mainScreen().bounds.height
let scrollViewContentHeight = 1200 as CGFloat

A little configuration is needed in viewDidLoad::

override func viewDidLoad() {
super.viewDidLoad()


scrollView.contentSize = CGSizeMake(scrollViewContentWidth, scrollViewContentHeight)
scrollView.delegate = self
tableView.delegate = self
scrollView.bounces = false
tableView.bounces = false
tableView.scrollEnabled = false
}

where I’ve turned off bouncing to keep things simple. The key settings are the delegates for the scroll view and the table view and having the table view scrolling being turned off at first.

These are necessary so that the scrollViewDidScroll: delegate method can handle reaching the bottom of the scroll view and reaching the top of the table view. Here is that method:

func scrollViewDidScroll(scrollView: UIScrollView) {
let yOffset = scrollView.contentOffset.y


if scrollView == self.scrollView {
if yOffset >= scrollViewContentHeight - screenHeight {
scrollView.scrollEnabled = false
tableView.scrollEnabled = true
}
}


if scrollView == self.tableView {
if yOffset <= 0 {
self.scrollView.scrollEnabled = true
self.tableView.scrollEnabled = false
}
}
}

What the delegate method is doing is detecting when the scroll view has reached its bottom. When that has happened the table view can be scrolled. It is also detecting when the table view reaches the top where the scroll view is re-enabled.

I created a GIF to demonstrate the results:

enter image description here

CGFloat tableHeight = 0.0f;


YourArray =[response valueForKey:@"result"];


tableHeight = 0.0f;
for (int i = 0; i < [YourArray count]; i ++) {
tableHeight += [self tableView:self.aTableviewDoc heightForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]];
}


self.aTableviewDoc.frame = CGRectMake(self.aTableviewDoc.frame.origin.x, self.aTableviewDoc.frame.origin.y, self.aTableviewDoc.frame.size.width, tableHeight);

After many trials and errors, this is what worked best for me. The solution has to solve two needs 1) determine who's scrolling property should be used; tableView or scrollView? 2) make sure that the tableView doesn't give authority to the scrollView until it has reached the top of it's table/content.

In order to see if the scrollview should be used for scrolling vs the tableview, i checked to see if the UIView right above my tableview was within frame. If the UIView is within frame, it's safe to say the scrollView should have authority to scroll. If the UIView is not within frame, that means that the tableView is taking up the entire window, and therefor should have authority to scroll.

func scrollViewDidScroll(_ scrollView: UIScrollView) {


if scrollView.bounds.intersects(UIView.frame) == true {
//the UIView is within frame, use the UIScrollView's scrolling.


if tableView.contentOffset.y == 0 {
//tableViews content is at the top of the tableView.


tableView.isUserInteractionEnabled = false
tableView.resignFirstResponder()
print("using scrollView scroll")


} else {


//UIView is in frame, but the tableView still has more content to scroll before resigning its scrolling over to ScrollView.


tableView.isUserInteractionEnabled = true
scrollView.resignFirstResponder()
print("using tableView scroll")
}


} else {


//UIView is not in frame. Use tableViews scroll.


tableView.isUserInteractionEnabled = true
scrollView.resignFirstResponder()
print("using tableView scroll")


}


}

hope this helps someone!

I tried the solution marked as the correct answer, but it was not working properly. The user need to click two times on the table view for scroll and after that I was not able to scroll the entire screen again. So I just applied the following code in viewDidLoad():

tableView.addGestureRecognizer(UISwipeGestureRecognizer(target: self, action: #selector(tableViewSwiped)))
scrollView.addGestureRecognizer(UISwipeGestureRecognizer(target: self, action: #selector(scrollViewSwiped)))

And the code below is the implementation of the actions:

func tableViewSwiped(){
scrollView.isScrollEnabled = false
tableView.isScrollEnabled = true
}


func scrollViewSwiped(){
scrollView.isScrollEnabled = true
tableView.isScrollEnabled = false
}

Modified Daniel's answer to make it more efficient and bug free.

@IBOutlet weak var scrollView: UIScrollView!
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var tableHeight: NSLayoutConstraint!


override func viewDidLoad() {
super.viewDidLoad()
//Set table height to cover entire view
//if navigation bar is not translucent, reduce navigation bar height from view height
tableHeight.constant = self.view.frame.height-64
self.tableView.isScrollEnabled = false
//no need to write following if checked in storyboard
self.scrollView.bounces = false
self.tableView.bounces = true
}


func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 20
}


func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
let label = UILabel(frame: CGRect(x: 0, y: 0, width: tableView.frame.width, height: 30))
label.text = "Section 1"
label.textAlignment = .center
label.backgroundColor = .yellow
return label
}


func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = "Row: \(indexPath.row+1)"
return cell
}


func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView == self.scrollView {
tableView.isScrollEnabled = (self.scrollView.contentOffset.y >= 200)
}


if scrollView == self.tableView {
self.tableView.isScrollEnabled = (tableView.contentOffset.y > 0)
}
}

Complete project can be seen here: https://gitlab.com/vineetks/TableScroll.git

None of the answers here worked perfectly for me. Each one had it's owned nuanced problem (needing to do a repeated swipe when one scrollview hit it's bottom, or the scroll indicator not looking correct, etc), so figured I'd throw in another answer.

Ole Begemann has a great write up on doing this exactly https://oleb.net/blog/2014/05/scrollviews-inside-scrollviews/

Despite being an old post, the concepts still apply to the current APIs. Additionally, there is a maintained (Xcode 9 compatible) Objective-C implementation of his approach https://github.com/eyeem/OLEContainerScrollView

I found an awesome library MXParallaxHeader

In Storyboard just set UIScrollView class to MXScrollView then magic happens.

I used this class to handle my UIScrollView when I embed a UIPageViewController container view. even you can insert a parallax header view for more detail.

Also, this library provides Cocoapods and Carthage

I attached an image below which represent UIViewHierarchy. MXScrollView Hierarchy

Maybe brute-force, but working perfectly if cell heights are the same: by the way, I use auto layout.

for the tableView (or collectionView or whatever), set an arbitrary height in storyboard, and make an outlet to class. Wherever appropriate, (viewDidLoad() or...) set the tableView's height big enough so that tableView doesn't need to scroll. (need to know the number of rows in advance) Then only the outer scrollView will scroll nicely.

I was struggling with this problem, too. There is a very simple solution.

In interface builder:

  1. create simple ViewController
  2. add a simple View, it will be our header, and constrain it to superview
    • it's the red view on the example below
    • I have added 12px from top, left and right, and set fixed height to 128px
  3. embed a PageViewController, making sure it is constrained to the superview, and not the header

ib

Now, here comes the fun part: for each page you add, make sure its tableView has an offset from top. Thats it. You can do if with this code, for example (assuming you use UITableViewController as a page):

override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
let tables = viewControllers.compactMap { $0 as? UITableViewController }
tables.forEach {
$0.tableView.contentInset = UIEdgeInsets(top: headerView.bounds.height, left: 0, bottom: 0, right: 0)
$0.tableView.contentOffset = CGPoint(x: 0, y: -headerView.bounds.height)
}
}

No messy scroll inside scroll inside table view, no mangling with delegates, no duplicated scrolls, perfectly natural behavior. If you can't see the header, it is probably because of the tableView background color. You have to set it to clear, for the header to be visible from under the tableView.

If you are facing problem with the nested scrolling issue , here tis the simplest solution for it .

  1. go to your design screen
  2. select your scroll view and then disable bounce on scroll
  3. if your view uses table view inside scroll view then disable bounce on scroll of the table view as well
  4. run and check it is solved

check how to disable bounce on scroll of a scroll view

check how to disable bounce on scroll of a tableview view

One easy trick, if you want to achieve it is replacing parent scrollview with normal container view. Adding a pan gesture on container view, you can play with top constraint of first view to assign negative values. You can keep a check of page View's origin if it achieves to top you can start assigning that value on content offset of the pageView's child view. Until user achieves the table view in a state of top most view in container view, you can keep page tableView's scrolling disabled and allow scrolling manually by setting content offset. So initially the page view height will be collapsed (or say out of screen) or less at bottom. Later on scrolling down it will expand to take more space.

Gesture will automatically stop responding if out of frames say on nav bar or other view outside container view.

Gestures are a key to user interactive transitions used in many apps. You can mimic scroll for a certain time with it.

In my case I'm using constraint for height like that:

self.heightTableViewConstraint.constant = self.tableView.contentSize.height
self.scrollView.contentInset.bottom = self.tableView.contentSize.height

SWIFT 5

I had some trouble using Vineet's answer for when I could not guarantee the scrollView content offset (Y) due to various different screen sizes. To resolve this, I changed the first trigger event of when the tableView's scroll gets enabled.

func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView.bounds.contains(button.frame) {
tableView.isScrollEnabled = true
}


if scrollView == tableView {
self.tableView.isScrollEnabled = (tableView.contentOffset.y > 0)
}
}

The scrollView.bounds.contains will check if a given element's frame is FULLY within the scrollView's visible content. I set this to a button that I have below the tableView. You could set this to your tableVIew's frame instead if your only condition is that your tableView is fully visible.

I left the original implementation of when to disable the tableView's scroll and it works very well.