开发小技巧:1.iOS初始化系统主题

(void)initSystemTheme
{
//UIBarButtonItem:去除返回按钮的默认文字、设置按钮的颜色
[[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -60) forBarMetrics:UIBarMetricsDefault];
[[UIBarButtonItem appearance] setTintColor:[UIColor whiteColor]];

//UINavigationBar:设置App中导航栏的颜色、标题颜色
[[UINavigationBar appearance] setBarTintColor:[UIColor colorWithRed:51.0/255 green:153.0/255 blue:255.0/255 alpha:1]];

[[UINavigationBar appearance] setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor whiteColor]}];

[[UITableView appearance] setBackgroundColor:[UIColor colorWithWhite:0.97 alpha:1]];

[[UITableView appearance] setSectionIndexBackgroundColor:[UIColor clearColor]];

[[UITabBar appearance] setBarTintColor:[UIColor colorWithWhite:0.94 alpha:1]];
}