navBar.barTintColor = [UIColor blackColor];
navBar.tintColor = [UIColor blueColor];
IOS7 中barTintColor改变UINavigationBar导航条的颜色,tintColor改变左右按钮的字的颜色
navBar.barTintColor = [UIColor blackColor];
navBar.tintColor = [UIColor blueColor];
IOS7 中barTintColor改变UINavigationBar导航条的颜色,tintColor改变左右按钮的字的颜色