Display RootViewController only when dismiss current ViewController - ios

Question

I'm doing an ios project without using any story board and xibs.
Here I've come out one problem on presenting my UIViewController.
Here is the senario:
My RootViewController has 2 UIButton's that can present ViewControllerA and ViewControllerB when being pressed.
-(IBAction)btnAclicked:(id)sender{
[self.navigationController presentViewController:ViewControllerA];
}
-(IBAction)btnBclicked:(id)sender{
[self.navigationController presentViewController:ViewControllerB];
}
And now inside ViewControllerA
I have a button to presentViewContollerB as well, and I want only the RootViewController to be displayed when I dismiss ViewContollerB.
In order to do this, I need to dismiss ViewControllerA first then presentViewControllerB. I know there is ways like using delegate to make it works, but I just want to know if there is any easier way to do this.
To be emphasised is that I want to use presentViewController only, not pushViewController. Thanks

Answer 1

I have an answer for your question,just do the following code,
in RootViewController.m
- (IBAction)gotoViewA:(id)sender
{
ViewControllerA *viewControllerA = [[ViewControllerA alloc]initWithNibName:#"ViewControllerA" bundle:nil];
[self presentViewController:viewControllerA animated:YES completion:nil];
}
- (IBAction)gotoViewB:(id)sender
{
ViewControllerB *viewControllerB = [[ViewControllerB alloc]initWithNibName:#"ViewControllerB" bundle:nil];
[self presentViewController:viewControllerB animated:YES completion:nil];
}
in ViewControllerA.m
- (IBAction)actionBackFromA:(id)sender
{
[self dismissViewControllerAnimated:YES completion:nil];
}
in ViewControllerB.m
- (IBAction)actionBackFromB:(id)sender
{
[self dismissViewControllerAnimated:YES completion:nil];
}

Answer 2

Use the completion block of presentviewcontroller,viz will executed first
[self presentViewController:goTo_B animated:YES completion:^{
//Dismiss A
[self dismissViewControllerAnimated:YES completion:nil];
}];
If this does not work,write dismiss and just after it present your new controller
[self dismissViewControllerAnimated:YES completion:nil];
[self.view.window.rootViewController presentViewController:goTo_B animated:YES completion:^{ }];

Answer 3

There's another way out, but i don't know whether its appropriate or not.
Create a property of type View Controller A in view controller B.
While presenting view controller B, assign an instance of View Controller A to the property in view Controller B.
[self presentViewController:goTo_B animated:YES completion:^{
goTo_B.propertyOfViewControllerA = self;
}];
After that while dismissing view controller B you can do the either of the two:
[self dismissViewControllerAnimated:YES completion:nil];
[propertyOfViewControllerA dismissViewControllerAnimated:YES completion:nil]
or
[self dismissViewControllerAnimated:YES completion:^{
[propertyOfViewControllerA dismissViewControllerAnimated:YES completion:nil]
}];