Ken Zhang questions

• iOS8 UISplitViewController: How to switch to master view in compact width window?
• Swift: Failed to assign value to a property of protocol?
• Xcode6: Is there any easy way to copy constrains between size classes?
• protocol typed array can't be downcast to concrete type array
• Swift: how can String.join() work custom types?
• Protocol doesn't support the "===" operator?
• is it possible to create a generic closure in Swift?

Ken Zhang answers