在TabBarController中的选项卡之间切换/导航

//I should not use navigation for this because the view would navigate
the present view to the view in tab 1 ; but the tab will still indicate Tab 2//

self.tabBarController.selectedIndex = 0;

transitionFromView:toView:duration:options:completion:

[UIView transitionFromView:self.view 
    toView:[[self.tabBarController.viewControllers objectAtIndex:0] view] 
    duration:1 /*or whatever time you want*/ 
    options:/*specify your animation transition here, they are found in the UIView documentation*/ 
    completion:(void (^)(BOOL finished))completion:^(BOOL finished) {
        if (finished) {
            tabBarController.selectedIndex = 0;
        }
    }];

selectedIndex

selectedViewController