Set UITableView content inset permanently

In my app I have a UISearchBar under UINavigationBar so it is always visible to user. In that case I had to set contentInset with extra 44px so the UIScrollView will be scrolling under UISearchBar (exactly like in Contacts.app). And there would be no problem with static UITableView's but in my case I have to reload it's contents, switch to UISearchDisplayControlleretc. So when I call:

[self.tableView setContentInset:UIEdgeInsetsMake(108, 0, 0, 0)];

Everything works until e.g. I pull to refresh... (for this I use SSPullToRefresh).

So my question is: How can I set contentInset permanently so I wouldn't have to worry about any changes happening to data inside UITableView?

Probably it was some sort of my mistake because of me messing with autolayouts and storyboard but I found an answer.

You have to take care of this little guy in View Controller's Attribute Inspector

It must be unchecked so the default contentInset wouldn't be set after any change. After that it is just adding one-liner to viewDidLoad:

[self.tableView setContentInset:UIEdgeInsetsMake(108, 0, 0, 0)]; // 108 is only example

iOS 11, Xcode 9 update

Looks like the previous solution is no longer a correct one if it comes to iOS 11 and Xcode 9. automaticallyAdjustsScrollViewInsets has been deprecated and right now to achieve similar effect you have to go to Size Inspector where you can find this:
Also, you can achieve the same in code:

if #available(iOS 11.0, *) {
    scrollView.contentInsetAdjustmentBehavior = .never
} else {
    automaticallyAdjustsScrollViewInsets = false
}

In Swift:

override func viewDidLayoutSubviews() {
      super.viewDidLayoutSubviews()
      self.tableView.contentInset = UIEdgeInsets(top: 108, left: 0, bottom: 0, right: 0)
}

automaticallyAdjustsScrollViewInsets is deprecated in iOS11 (and the accepted solution no longer works). use:

if #available(iOS 11.0, *) {
    scrollView.contentInsetAdjustmentBehavior = .never
} else {
    automaticallyAdjustsScrollViewInsets = false
}

Add in numberOfRowsInSection your code [self.tableView setContentInset:UIEdgeInsetsMake(108, 0, 0, 0)];. So you will set your contentInset always you reload data in your table

After one hour of tests the only way that works 100% is this one:

-(void)hideSearchBar
{
    if([self.tableSearchBar.text length]<=0 && !self.tableSearchBar.isFirstResponder)
    {
        self.tableView.contentOffset = CGPointMake(0, self.tableSearchBar.bounds.size.height);
        self.edgesForExtendedLayout = UIRectEdgeBottom;
    }
}

-(void)viewDidLayoutSubviews
{
    [self hideSearchBar];
}

with this approach you can always hide the search bar if is empty