Custom animation when switching tab/viewcontroller in UITabBarController
===

I'd like to make the tabbarcontroller tab switching animation similar to pop and push animation of navigation controller.

That's means if I select a tab at the left of the current tab, the view of new viewcontroller move into the screen from the left, and the view of old/current viewcontroller move out of screen to the right (similar to pop). 

I can only achieve this at the moment but I don't know how to implement slide in/out effect.

Thank you!

(BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController:

    	UIView *fromView = tabBarController.selectedViewController.view;
		NSInteger fromIndex = tabBarController.selectedIndex;
		UIView * toView = [viewController view];
		NSInteger toIndex = [[tabBarController viewControllers] indexOfObject:viewController];

		[UIView transitionFromView:fromView
							toView:toView
						  duration:0.3
						   options:UIViewAnimationOptionTransitionCrossDissolve
						completion:^(BOOL finished) {
							if (finished) {
								tabBarController.selectedIndex = toIndex;
							}
						}];
