set border to textformfield in flutter code example
Example: textfield border flutter
decoration: new InputDecoration(
border: new OutlineInputBorder(
borderSide: new BorderSide(color: Colors.teal)),
hintText: 'Tell us about yourself',
helperText: 'Keep it short, this is just a demo.',
labelText: 'Life story',
prefixIcon: const Icon(
Icons.person,
color: Colors.green,
),
prefixText: ' ',
suffixText: 'USD',
suffixStyle: const TextStyle(color: Colors.green)),
),