self.tabBarController = [[UITabBarController alloc] init];
HomeViewController *homeVC = [[HomeViewController alloc] init];
UINavigationController *nav1 = [[UINavigationController alloc] initWithRootViewController:homeVC];
UITabBarItem *bar1 = [[UITabBarItem alloc]initWithTitle:@"首页" image:[UIImage imageNamed:@"tab_home"] tag:101];
//设置选中后的背景图片
[bar1 setSelectedImage:[UIImage imageNamed:@"tab_home_select"]];
//把bar上的字体向上移4个像素。
nav1.tabBarItem.titlePositionAdjustment = UIOffsetMake(0, -4);
nav1.tabBarItem = bar1;
//设置背景图片
[[UITabBar appearance] setBackgroundImage:[UIImage imageNamed:@"tab_bacgground"]];
if (IOSSystemVersion>=7) {
//设置选中后bar的颜色，图片和字体都改变
[[UITabBar appearance]setTintColor:COLOR_HEX_RGB(0xff783a)];
}else
{
// [[UITabBar appearance] setBackgroundImage:[UIImage imageNamed:@"tab_bacgground"]];
//设置选中后字体的颜色，低版本ios
[[UITabBarItem appearance] setTitleTextAttributes: [NSDictionary dictionaryWithObjectsAndKeys:COLOR_HEX_RGB(0xff6600),UITextAttributeTextColor,nil]forState:UIControlStateSelected];
}
UITabBarController，UITabBarItem设置
原文：http://blog.csdn.net/xiao562994291/article/details/42710291