Dynamically-sized UITableView in UIScrollView with Auto-Layout

Question

There are a million questions about auto-layout and UIScrollViews, but I think this is something different.

I have a construct that looks like this:

The white background is a UIView which acts as a container within a UIScrollView (the typical setup for get a scroll view to build its own content size so it scrolls properly based on the container view).

TableView 1 and TableView 2 need to have their heights be dynamic. I don't want them scrolling, so I need to set their frame height equal to their content height.

I have IBOutlets for the height constraint for each of these, and can adjust them with no problem.

The issue arises when I try to adjust the height of the container view. Ultimately, I would like to not have to mess with it and let that view resize automatically based on its content, but that does not seem to be working (if I leave off the height of the container view, I get warnings/errors in IB about the constraints).

If I create an outlet to the container view's height constraint and set it, I get an assert fail:

*** Assertion failure in -[UIView layoutSublayersOfLayer:], /SourceCache/UIKit_Sim/UIKit-2935.137/UIView.m:8803

I am doing the constraint adjusting in viewDidLayoutSubviews like this:

- (void)viewDidLayoutSubviews {
    self.orderItemTableViewHeightConstraint.constant = self.orderItemTableView.contentSize.height - [self tableView:self.orderItemTableView heightForHeaderInSection:0];
    self.shippingOptionTableViewHeightConstraint.constant = self.shippingMethodTableView.contentSize.height;
    self.scrollViewContainerViewHeightConstraint.constant = self.cardInfoLabel.$bottom + 60;
}

I believe the problem is setting the container view's height constraint is causing some recursion or something...

The questions:

1. IS there a way to let the container view's height be fluid based on its content in this situation?
2. If not, how do I handle this programmatically? Am I altering the constraints in the wrong place or something?

Thanks for any input!

Answer 1

Ok, well, just shotgunning code here, but after much trial and error, this seems to resolve the assert failure and gives the desired result:

- (void)viewDidLayoutSubviews {
    self.orderItemTableViewHeightConstraint.constant = self.orderItemTableView.contentSize.height - [self tableView:self.orderItemTableView heightForHeaderInSection:0];
    self.shippingOptionTableViewHeightConstraint.constant = self.shippingMethodTableView.contentSize.height;

    [self.view layoutIfNeeded];

    self.scrollViewContainerViewHeightConstraint.constant = self.cardInfoLabel.$bottom + 60;

    [self.view layoutIfNeeded];
}

Would really like to have this more dynamic, but will take the win at this point in the game!

Hope this helps someone else.