chnage bordersize of textfields flutter code example
Example: text field outline flutter
TextField(
decoration: new InputDecoration(
focusedBorder: OutlineInputBorder(
borderSide: BorderSide(color: Colors.greenAccent, width: 5.0),
),
enabledBorder: OutlineInputBorder(
borderSide: BorderSide(color: Colors.red, width: 5.0),
),
hintText: 'Mobile Number',
),