How to make rounded border for dropdownbutton in flutter?

Question

How to Add Rounded Rectangle Border? Below Code didn't result in any border on screen.

Container(margin: EdgeInsets.only(top: 10.0, right: 10.0, left: 10.0),
 width: double.infinity,
 // decoration: ShapeDecoration(
 //  shape: RoundedRectangleBorder(
 //   borderRadius:BorderRadius.all(Radius.circular(5.0)),
 //                             ),

 child: DropdownButtonHideUnderline(
  child: Container(
   margin: EdgeInsets.only(
    left: 10.0, right: 10.0),
     child: new DropdownButton<UserTest>(...),
                           ),
                          ),
                   ),

Answer 1

You need to specify the side: property. By default it is BorderSide.none.

      decoration: ShapeDecoration(
        shape: RoundedRectangleBorder(
          side: BorderSide(width: 1.0, style: BorderStyle.solid),
          borderRadius: BorderRadius.all(Radius.circular(5.0)),
        ),
      ),