ios 11 - UIButton inside UIBarButtonItem causes an autolayout error

Question

I\'ve a known issue with adding a UIButton into UIBarButtonItem. I\'ve tried to add auto layout constraints as suggested in stackoveflow but I\'m getting an error described

Answer 1

The bar button is constrained to the left and right, so the width constraint has to be broken. You can fix this by adding a flexible space to the toolbar. This allows you to contraint the width of the button and have the flexible space fill the rest.

Obj C:

UIBarButtonItem *flexItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];
[self setToolbarItems:[NSArray arrayWithObjects:self.sortCollection, flexItem, nil]];

Swift:

let flexItem = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
toolbar.setItems([barButtonItem, flexItem], animated: false)