iOS 7 Table view fail to auto adjust content inset

Question

I am transiting my project to iOS7. I am facing a strange problem related to the translucent navigation bar.

I have a view controller and it has a tableview as subview (let's call it ControllerA) . I init a new uinavigationcontroller with the controllerA and present it modally using presentviewcontroller. The presented view controller's table view is blocked by the navigation bar. I set the automaticallyAdjustsScrollViewInsets to YES but the result did not change. I knew I can set the edgesForExtendedLayout to UIRectEdgeNone, but it will make the navigation bar no more translucent.

After that, I tried to create a new view controller for testing. It contains almost the same elements. But the result is much different. The table view content does not get blocked.

Conclusion

1. Two View Controllers' automaticallyAdjustsScrollViewInsets set to YES
2. The project is not using storyboard
3. The first one is created at Xcode 4.6, The second one is newly created on Xcode 5
4. I have compared two classes xib and code, not much different

Answer 1

I have found the answer on apple developer forum. There are two different case.

The first one, the view controller added is a UITableViewController. And the issue should not be appeared since apple will auto padding it.

The second one, the view controller is NOT a UITableViewController. And in the view hierarchy, it contains a UITableView. In this case, if the UITableview(or ScrollView) is the viewController's mainview or the first subview of the mainview, it will work. Otherwise, the view controller doesn't know which scroll view to padding and it will happen the issue.

In my case, the view controller is the second one. And there is a background image view as the first subview of the main view. So, it fails.

Here is the Apple developer forum link (need developer account to access): https://devforums.apple.com/message/900138#900138

Answer 2

If you want the view to underlap the navigation bar, but also want it positioned so the top of the scrollview's content is positioned below the navigation bar by default, you can add a top inset manually once the view is laid out. This is essentially what the view layout system does when the top-level view is a scroll view.

-(void)viewDidLayoutSubviews {
    if ([self respondsToSelector:@selector(topLayoutGuide)]) {
        UIEdgeInsets currentInsets = self.scrollView.contentInset;
        self.scrollView.contentInset = (UIEdgeInsets){
            .top = self.topLayoutGuide.length,
            .bottom = currentInsets.bottom,
            .left = currentInsets.left,
            .right = currentInsets.right
        };
    }
}

Answer 3

Based on Tony's answer I was able to get around this problem programatically with temporarily sending the table view to the back, let the adjustments be made and then send the background view back to the back. In my case there is no flickering to this approach.

In the View Controller:

- (void)viewWillLayoutSubviews {
    [super viewWillLayoutSubviews];

    [self.view sendSubviewToBack:self.tableView];
}

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];

    [self.view sendSubviewToBack:self.backgroundView];
}

Obviously if there are other subviews on self.view you may need to re-order those too.

Answer 4

There's probably too many answers on this already, but I had to take Christopher's solution and modify it slightly to support view resizing and allowing the content inset to be changed in a subclass of the UIViewController.

@interface MyViewController ()

@property (weak, nonatomic) IBOutlet UIScrollView *scrollView;
@property (assign, nonatomic) UIEdgeInsets scrollViewInitialContentInset;

@end


@implementation MyViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    [self setScrollViewInitialContentInset:UIEdgeInsetsZero];
}

- (void)viewWillLayoutSubviews {
    [super viewWillLayoutSubviews];

    if (UIEdgeInsetsEqualToEdgeInsets([self scrollViewInitialContentInset], UIEdgeInsetsZero)) {
        [self setScrollViewInitialContentInset:[self.scrollView contentInset]];
    }
}

- (void)viewDidLayoutSubviews {
    [super viewDidLayoutSubviews];

    UIEdgeInsets scrollViewInset = [self scrollViewInitialContentInset];

    if (UIEdgeInsetsEqualToEdgeInsets(scrollViewInset, UIEdgeInsetsZero) {

        if ([self respondsToSelector:@selector(topLayoutGuide)]) {
            scrollViewInset.top = [self.topLayoutGuide length];
        }

        if ([self respondsToSelector:@selector(bottomLayoutGuide)]) {
            scrollViewInset.bottom = [self.bottomLayoutGuide length];
        }

        [self.scrollView setContentInset:scrollViewInset];
    }
}

@end

To explain the point:

Any subclass of MyViewController can now modify the contentInset of scrollView in viewDidLoad and it will be respected. However, if the contentInset of scrollView is UIEdgeInsetsZero: it will be expanded to topLayoutGuide and bottomLayoutGuide.

Answer 5

@Christopher Pickslay solution in Swift 2:

override func viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()

    let topInset = topLayoutGuide.length
    inTableView.contentInset.top = topInset
    inTableView.contentOffset.y = -topInset
    inTableView.scrollIndicatorInsets.top = topInset
}

Answer 6

Yeah - a bit annoying.

I have a nib with a single tableview within the main view, not using autolayout. There is a tabbar, navigationbar and a statusbar and the app needs to work back to 5.0. In Interface builder that neat 'see it in iOS7 and iOS6.1 side-by-side' thing works, showing the tables neatly fitting (once the iOS6/7 deltas were set properly).

However running on a device or simulator there was a large gap at the top of the table, which was as a result of a content inset (which pretty much matched by iOS6/7 vertical delta) that was set to zero in the nib.

Only solution I got was in viewWillAppear to put in [_tableView setContentInset:UIEdgeInsetsZero].

Another ugly hack with a pretty on-screen result.....

Answer 7

[self.navigationController setNavigationBarHidden:YES animated:YES]; 

in:

- (void)viewDidLoad