title: What does actutally Bottom overflowed by 123 pixels mean in flutter
body: <p>I am learning flutter and currently switched from android to flutter.In flutter i mostly get an error something like 
  <code>bottom overflowed by 234 pixels</code> or <code>renderbox overflowed by 340 pixels</code>.And i fixes that problem by increase the height of the widget.If so then how to know that what much size giving to widget.I mean in android we can  declare the height of the layout to be wrap content and its works perfectly.Please explain me that how can i avoid this situation because if i fixes the issue by changing the height of widget in one device then in devices of other screen sizes if throws same error ?Here is a image which throws an error.Ignore the red error , see the error in below screen.Thanks in advance.</p>
  
  <p>!<a href="https://imgur.com/a/PsZzeMp" rel="nofollow noreferrer">https://imgur.com/a/PsZzeMp</a></p>