Auto Layout 的新特性

Incrementally Adopting Auto Layout

1. 简单的resize，不用约束

• Autoresizing masks will translate into constraints at runtime

translatesAutoresizingMaskIntoConstraints == true

2. 复杂的用约束

• Autoresizing masks are ignored

translatesAutoresizingMaskIntoConstraints == false

3. Incremental Adoption

• Auto Layout + Autoresizing masks

Design and Runtime Constraints

1. Placeholder Constraints
2. Design Time Intrinsic Size
   At runtime,

override var intrinsicContentSize: CGSize

3. Turn Off Ambiguity Per View