title: getting render flow error and forced take singlechildscrollview
body: <p>I am creating simple product detail screen where I have taken column inside body,
  setting height based on media query</p>
  <p>a simple SizedBox is taken with the height of mediaquiry's height size</p>
  <p>but I am getting error <code>A RenderFlex overflowed by 80 pixels on the bottom</code></p>
  <p>and if I take singlechildscrollview it solves....but here I can't understand what's my mistake....</p>
  <p>is it because of appbar's height? and if it is so..how to count appear height...so that I can deduct from size of body</p>
  <p>here is my simple code, I can solve with SingleChildScrollView but main thing is I am not getting what issue is..</p>
  <pre><code>class DetailScreen extends StatelessWidget {
    final Product product;
  
    DetailScreen({required this.product});
  
    @override
    Widget build(BuildContext context) {
      Size size=MediaQuery.of(context).size;
      print(size.toString());
      return Scaffold(
        backgroundColor: product.color,
        appBar: buildAppbar(context),
        body: Column(children: [
          SizedBox(
            height: size.height,
            child: Stack(
            children: [
              Container(
                height: 10,
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.only(
                    topLeft: Radius.circular(24),
                    topRight: Radius.circular(24),
  
                  ),
                ),
  
              )
  
            ],
          ),
  
          ),
        ],),
      );
    }
  
    AppBar buildAppbar(BuildContext context)
    {
      return AppBar(
        backgroundColor: product.color,
        elevation: 0,
        leading: IconButton(icon: SvgPicture.asset('assets/icons/back.svg',color: Colors.white,),onPressed: (){
          Navigator.pop(context);
        },),
        actions: [
          IconButton(onPressed: (){}, icon: SvgPicture.asset('assets/icons/search.svg',color: Colors.white,)),
          SizedBox(width: 5,),
          IconButton(onPressed: (){}, icon: SvgPicture.asset('assets/icons/cart.svg',color: Colors.white,)),
          SizedBox(width: 20,),
        ],
  
      );
    }
  }
  
  
  </code></pre>