在swift中更改UINavigationBar中UIBarButtonItem的宽度

Question

我需要在swift 2.0中为我的导航栏按钮设置框架

我试过这段代码

self.navigationController!.navigationBar.drawRect(CGRectMake(0, 0, 30, 30)) 

但它不会起作用

提前致谢

Answer 1

// Swift 3
let backButton = UIButton(frame: CGRect(x: 0, y: 0, width: 30, height: 30))
backButton.setBackgroundImage(UIImage(named: "img"), for: .normal)
backButton.addTarget(self, action: "action:", for: .touchUpInside)
self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backButton)

// Swift 2
let backButton = UIButton(frame: CGRect(x: 0, y: 0, width: 30, height: 30))
backButton.setBackgroundImage(UIImage(named: "img"), forState: .Normal)
backButton.addTarget(self, action: "action:", forControlEvents: .TouchUpInside)
self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: backButton)