Change tabbarController's tab programmatically with animation

Question

I want to change tab through code with animation. Exact scenario is that there are 2 tabs with below hierarchy.

First tab
  - Navigation controller
    - Log         


        

Answer 1

Below is the code I used to animate screens with slide in-out effect. Found on SO question.

- (void)logoutButtonPressed
{
    [self.navigationController popToRootViewControllerAnimated:NO];

    [self animateTransitionBetweenControllers];
}

// Animates view transition that happens from screen with logout button to login screen
- (void)animateTransitionBetweenControllers
{
    // Get the views to animate.
    UIView * fromView = self.tabBarController.selectedViewController.view;
    UIView * toView = [[self.tabBarController.viewControllers objectAtIndex:0] view];

    // Get the size of the view.
    CGRect viewSize = fromView.frame;

    // Add the view that we want to display to superview of currently visible view.
    [fromView.superview addSubview:toView];

    // Position it off screen. We will animate it left to right slide.
    toView.frame = CGRectMake(-self.view.bounds.size.width, viewSize.origin.y, toView.bounds.size.width, viewSize.size.height);

    // Animate transition
    [UIView animateWithDuration:0.3 delay:0.0 options:UIViewAnimationOptionTransitionNone animations:^{
        // Animate the views with slide.
        fromView.frame = CGRectMake(self.view.bounds.size.width, viewSize.origin.y, toView.bounds.size.width, viewSize.size.height);
        toView.frame = CGRectMake(0, viewSize.origin.y, toView.bounds.size.width, viewSize.size.height);
    } completion:^(BOOL finished) {
        if (finished)
        {
            // Remove the old view.
            [fromView removeFromSuperview];
            self.tabBarController.selectedIndex = 0;
        }
    }];
}