give circular border to container flutter code example

Example 1: round border container flutter

Container(
  decoration: BoxDecoration(
    border: Border.all(
      color: Colors.red[500],
    ),
    borderRadius: BorderRadius.all(Radius.circular(20))
  ),
  child: ...
)

Example 2: border at circleAvatar flutter

CircleAvatar(
    radius: 30,
    backgroundColor: Colors.teal,
    child: CircleAvatar(
      backgroundImage: AssetImage('assets/appdev.png'),
      radius: 28,
    ),
  ),