31

I have a problem with autolayout(maybe) and my scrollview!

My Problem

  1. I scroll down View

2.Then I push to another View

3.Then I go back and the scrollview looks like that and I'm not able to scroll to the highest point.(I see it in the bouncing of the scrollview) Scrollview

Can anybody help me?

Mathias Aichinger
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9 Answers9

40

The following code snippet in the containing view controller also seems to solve the problem, without relying on explicit sizes:

- (void)viewDidDisappear:(BOOL)animated {
  [super viewDidDisappear:animated];
  self.mainScrollView.contentOffset = CGPointZero;
}

It does reset the content offset to the origin, but it seems that so do the other answers.

user1071136
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  • this works! but when i set it back to the right value(in viewdidappear) it is flickering! so I continue looking for a better way.... – Mathias Aichinger Nov 28 '12 at 14:46
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    set right offset in viewDidLayoutSubviews back and everything is fine :) – Mathias Aichinger Nov 29 '12 at 10:50
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    This is an unbelievably and frustrating bug/issue. People aren't prepared to deal with this bug when setting things up in Interface Builder. – Ethan Mick Apr 09 '13 at 17:49
  • I had to use this fix also, but before I presented my UIViewController I let the scrollView scroll to the top. My scrollView was off-screen so I had no flickering. But you could create a method to reset the scrollview to its origin point and call it after 1 second or so (performSelector:withObject:afterDelay:); when you start presenting your UIViewController. – Yannick Sep 17 '13 at 12:59
  • Looks like that Apple has fixed this issue in the newest iOS! :) – Mathias Aichinger Sep 25 '13 at 07:39
  • @matchi1992 I have the most recent version, and I'm facing this issue. Can someone tell why this happen? please. – Frade Nov 03 '14 at 14:55
  • @Frade do you found the workaround? I have Xcode 6.2 – Beto Mar 28 '15 at 00:45
  • @Beto Bens, not exactly a workaround. I redesigned the the interface with new/different auto-layout constraints. First I had lots of uibuttons inside a single view, and I was trying to place the view in the scrollView. I took out the view, so i placed all buttons and views directly on scrollView, I fixed one relative to scrollView, and the others relative to the first.. And it worked. – Frade Mar 30 '15 at 10:03
11

if you are still searching for an answer i found it today after two days of headbanging the wall. I will just paste you the code, but the most important thing is when you load your scrollView..

    -(void)viewWillAppear:(BOOL)animated{

    [scrollView setFrame:CGRectMake(0, 0, 320, 800)];
}

-(void)viewDidAppear:(BOOL)animated
{
    [scrollView setScrollEnabled:YES];
    [scrollView setContentSize:CGSizeMake(320, 800)];

}

all this is loaded before -(void)viewDidLoad

notice the height is in both instances 800, which is crucial for resolving this problem. good luck with your project ;)

kadore
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6

I was using adam's solution, but started to have problems when i was dismissing with animated:YES. In my code, content offset gets set a while after viewWillAppear (as viewWillAppear appears to be too soon).

- (void)viewDidDisappear:(BOOL)animated
{
    self.scrollOffsetToPersist = self.scrollView.contentOffset;
    self.scrollView.contentOffset = CGPointZero;

    [super viewDidDisappear:animated];
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];

    [[NSOperationQueue mainQueue] addOperationWithBlock:^
     {
         self.scrollView.contentOffset = self.scrollOffsetToPersist;
     }];
}

EDIT: another, better way is to reset it back in viewDidLayoutSubviews :)

- (void)viewDidLayoutSubviews
{
    [super viewDidLayoutSubviews];

    if(!CGPointEqualToPoint(CGPointZero, self.scrollOffsetToPersist))
    {
        self.scrollView.contentOffset = self.scrollOffsetToPersist;
        self.scrollOffsetToPersist = CGPointZero;
    }
}
Kukosk
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  • Note that if you set it in viewDidLayoutSubviews, you may need to also save the offset in viewDidDisappear: or scrollview offset will jump to zero when you present a modal view controller and won't reset properly. I filed a bug with Apple on this behavior as well: http://openradar.appspot.com/radar?id=3011407 – DesignatedNerd May 21 '13 at 23:09
  • I solve my problem using `NSoperationQueue` putting in the `viewDidLayoutSubviews` method and set `contectsize` of scrollview.Thanks @kukosk – Ilesh P Aug 22 '15 at 07:01
3

This isn't great but I beat auto-layout (definitely not the correct way but I was sick of trying!) by setting the content size in viewDidAppear after autolayout happens, setting the scrollOffset and persisting the scroll offset in viewDidDisappear, and then setting the scroll offset back to it's persisted state in viewDidAppear.

Like this:

-(void)viewDidAppear:(BOOL)animated{
    [super viewDidAppear:YES];
    self.scrollView.contentSize = self.scrollViewInnerView.frame.size;
    self.scrollView.contentOffset = [self.scrollOffsetToPersist CGPointValue];

}

-(void)viewDidDisappear:(BOOL)animated{
    [super viewDidDisappear:YES];
    self.scrollOffsetToPersist = [NSValue valueWithCGPoint:self.scrollView.contentOffset];
    self.scrollView.contentOffset = CGPointZero;
}

Not at all elegant, but works so thought I'd share.

Adam Waite
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    apple wrote the same thing... probably the best solution so far... but I think viewDidLayoutSubviews is the better position to set the offset back – Mathias Aichinger Dec 10 '12 at 09:28
  • Yep this is what worked for me. A simple idea such as resizing subviews in a scroll view, the execution is rather complex... Spent hours messing around with UIScrollView and autolayout before finally settling on this. – Michael Apr 17 '13 at 23:40
1

I use an UITabBarController and different views with auto layout. The views are longer than the screen of the device. Switching from one tab to the other lead sometimes to the problem you describe. This only happened if the view has been scrolled down before the switch. I tried all the advice here but this did not work for my case. My solution was to scroll up again before leaving the view. At least a work around for this bug in iOS 6:

-(void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    [scrollView setContentOffset:CGPointZero animated:NO];
}
Holger Schmeken
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1

The issue cause ScrollView was set ContentOffset before AutoLayout applied. the solution is:

Create private property

@property (assign,nonatomic) CGPoint scrollviewContentOffsetChange;

Add code to view method

- (void)viewWillAppear:(BOOL)animated {
  [super viewWillAppear:animated];
  self.scrollView.contentOffset = CGPointZero;
}

- (void)viewWillDisappear:(BOOL)animated {
  [super viewWillDisappear:animated];
  self.scrollviewContentOffsetChange = self.scrollView.contentOffset;
}

- (void)viewDidLayoutSubviews {
  [super viewDidLayoutSubviews];

  self.scrollView.contentOffset = self.scrollviewContentOffsetChange;
}
Ratha Hin
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1

have you tried this?

self.automaticallyAdjustsScrollViewInsets = NO;

In my case this was what solved my problem.

Lukas
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0

I had the same problem. Turned out I was setting a constraint on the content view aligning the it's y-center to the superview's y-center. When I deleted this constraint it worked just fine.

mimc
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0

try this

@property (nonatomic, assign) CGPoint scrollViewContentOffsetChange;

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    self.scrollView.contentOffset = CGPointZero;
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    self.scrollViewContentOffsetChange = _scrollView.contentOffset;
}

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];
    _scrollView.contentOffset = self.scrollViewContentOffsetChange;
}
Jimvanced
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