替换导航栏按钮

前言：用UIBarButtonItem替换很简单，本文说的当然不是这一种了。下面介绍一种用UIButton来替换导航栏按钮的方法

// 替换 navigation 左侧按钮
    UIButton * backToHomeBtn = [ UIButton buttonWithType : UIButtonTypeCustom ];
    [backToHomeBtn setBackgroundImage :[ UIImage imageNamed : @"fanhui2@3x" ]
                               forState : UIControlStateNormal ];
    [backToHomeBtn addTarget : self action : @selector (backToHomeBtnDidClick:)
              forControlEvents : UIControlEventTouchUpInside ];
    backToHomeBtn. frame = CGRectMake ( 0 , 0 , 50 , 25 );
    UIBarButtonItem *backBtn = [[ UIBarButtonItem alloc ] initWithCustomView :backToHomeBtn];

    self.navigationItem.leftBarButtonItem = backBtn;