Here is my code as a gist ( an interactive version of my code in dartpad.dev )
A quick rundown on what I was trying to do with this app:
I have two page
/Where I want to type a String in a TextField , which will simultaneously start appearing in theappBar, and there is another button , which when you press , will take you to another page (HomeWidget ) but with thetextthat you wrote in the/page. I want this transition to be like a Hero Animation , where the text from theappBarof/pagefliesintobodyofInfo
I was previously Using
Navigator.pushNamed(context, "Info", arguments: {"text": myController.text});
To route to the new page and also pass the text that I want to display over there.And I was able to do it , but even in Profile mode , the animation is too fast 
But the answer I got coming from this Question was to use
Navigator.push(
context,
PageRouteBuilder(
transitionDuration: Duration(seconds: 2),
pageBuilder: (_, __, ___) => Page2())
),
But the problem is , the Navigator.push(context, PageRouteBuilder( ... ) ) doesn't let you pass arguments , which I definitely want to be able to do.