//导航栏按钮设置
//导航栏背景色全局设置（写在appdelegate里）
[[UINavigationBar appearance] setBarTintColor:kMainColorOfApp];
//按钮标题颜色设置
[self.navigationController.navigationBar setTintColor:[UIColor blackColor]];
//按钮标题设置
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"取消" style:UIBarButtonItemStylePlain target:self action:@selector(onClickCancel)];
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"保存" style:UIBarButtonItemStylePlain target:self action:@selector(onClickSave)];
self.navigationItem.title = @"服务地区";
修改导航条背景颜色
self.navigationController.navigationBar.barTintColor = [UIColor colorWithHexString:@"#2295f2"];
设置了导航条背景颜色，会导致按钮标题颜色改变，通过以下方法修改
self.navigationController.navigationBar.tintColor = [UIColor whiteColor];
自定义的按钮图片距屏幕边缘太远，可通过以下代码修改
系统默认的rightBarButtonItem边距
self.navigationItem.leftBarButtonItem.imageInsets = UIEdgeInsetsMake(0,-20,0,0);
self.navigationItem.rightBarButtonItem.imageInsets = UIEdgeInsetsMake(0,-10,0,10);
