如何从UnsafeMutablePointer< Void>转换到具体对象类型
我已经创建了一个KVO观察者,并像这样传递了一个自定义类作为上下文
class Info : NSObject { } class Foo : NSObject { dynamic var property = "" } var info = Info() class Observing : NSObject { func observe1(object: NSObject) { object.addobserver(self,forKeyPath: "property",options: .New,context: &info) } override func observeValueForKeyPath(keyPath: String,ofObject object: AnyObject,change: [NSObject : AnyObject],context: UnsafeMutablePointer<Void>) { println("observed \(keyPath) change:'\(change)' context: \(context)") } } let o = Observing() var object = Foo() o.observe1(object) object.property = "new value"
我想知道如何将上下文转换回Info类