I have a Custom TabViewController that adds subviews to the current view depending on what UITabBarItem is selected. For the different subviews I have simulated a Navigation Bar and a Tab Bar so that the sub views match the format when they are displayed. The one sub view, which contains a UILabel, displays fine however the sub view with the UITableView overlaps the UITabBar. However in the Interface Builder I have sized the UITableView to not cut off the UITabBar.
Adding the subview in the TabViewController
[self.view addSubview:subViewController.view];


You haven’t provided enough information to be sure, but I think you are adding the table view to the wrong view. Assuming that
selfis your UITabBarController subclass, you are adding the custom view in the view that covers the entire screen, including the tab bar.Instead, you should be adding the custom views to the selected view controller’s view:
This will limit the stuff you are adding to the tab bar controller’s content area, and won’t overlap the tab bar.
I’m not sure what you are trying to accomplish with this approach, though: it seems like it would make more sense to add subViewController to the set of view controllers that the UITabBarController manages, rather than messing around with the view hierarchy.
Also, there is nothing inherently wrong with loading views from a nib and then manipulating them in code. “Mixing styles” is not a problem.