The Core iOS Developer’s Cookbook, Fifth Edition

Recipe: Creating Fixed-Size Constrained Views

When working with constraints, start thinking about your views in a new way. You don’t just set a frame and expect the view to stay where and how big you left it. Constraint layout uses an entirely new set of assumptions.

Here’s how you might have written a utility method to create a label before Auto Layout:

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- (UILabel *)createLabelTheOldWay:(NSString *)title {     UILabel *label = [[UILabel alloc]        initWithFrame:CGRectMake(0.0f, 0.0f, 100.0f, 100.0f)];     label.textAlignment = NSTextAlignmentCenter;     label.text = title;     return label; }

With Auto Layout, you approach code-level view creation in a new way. Your code adds constraints that adjust the item’s ...