在Swift中获取UIBarButtonItem的框架？

Question

我怎么能在swift中得到rightbarbuttonItem的框架？我发现了这个:UIBarButtonItem:我怎样才能找到它的框架？但它说无法将NSString转换为UIView,或者无法将NSString转换为String:

let str : NSString = "view" //or type String
let theView : UIView = self.navigationItem.rightBarButtonItem!.valueForKey("view")//or 'str'

目标是删除rightBarButtonItem,改为添加imageView,并使用fadeOut效果移动它.

谢谢

Answer 1

你应该尝试像:

var barButtonItem = self.navigationItem.rightBarButtonItem!
var buttonItemView = barButtonItem.valueForKey("view")

var buttonItemSize = buttonItemView?.size

编辑(Swift 3):

var barButtonItem = self.navigationItem.rightBarButtonItem!
let buttonItemView = barButtonItem.value(forKey: "view") as? UIView
var buttonItemSize = buttonItemView?.size

Answer 2

在 Swift4、XCode9 中

    for view in (self.navigationController?.navigationBar.subviews)! {
        if let findClass = NSClassFromString("_UINavigationBarContentView") {
            if view.isKind(of: findClass) {
                if let barView = self.navigationItem.rightBarButtonItem?.value(forKey: "view") as? UIView {
                    let barFrame = barView.frame
                    let rect = barView.convert(barFrame, to: view)
                }
            }
        }
    }