改变tabbar的高度做法

1 UITabBarController *tabBarController =[[UITabBarController alloc] init];
2     CGRect frame = self.window.bounds;
3     tabBarController.tabBar.frame = CGRectMake(0, CGRectGetHeight(frame) - 98, CGRectGetWidth(frame), CGRectGetHeight(frame));
4     UIView *transitionView = [[tabBarController.view subviews] objectAtIndex:0];
5     frame.size.height = CGRectGetHeight(frame) - 98;
6     transitionView.frame = frame;