我想全局更改导航栏后退按钮，所以我有这个:UIBarButtonItem.appearance().setBackButtonTitlePositionAdjustment(UIOffsetMake(-100,-5000),forBarMetrics:.Default)varbackImage:UIImage=UIImage(named:"BackButton")!backImage=backImage.imageWithAlignmentRectInsets(UIEdgeInsetsMake(0,0,0,20))UINavigationBar.appearance().backInd