Container View is fixed with Bottom half of the screen, On Button click current container view will replace with the new View Controller. Each sub view have a different size in height. Sub view Scroll is not working. I checked with many answers but solutions found. The code is
UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:@"Main" bundle:[NSBundle mainBundle]];
UIViewController *viewController = nil;
viewController = [storyBoard instantiateViewControllerWithIdentifier:@"First"];
// lets add it to container view
[viewController willMoveToParentViewController:self];
[self.containerViewController addSubview:viewController.view];
[self addChildViewController:viewController];
[viewController didMoveToParentViewController:self];