Make buttons in a row have the same width in flutter

You can use a Row wrapping your children with Expanded:

Row(
  children: <Widget>[
    Expanded(
      child: RaisedButton(
        child: Text('Approve'),
        onPressed: () => null,
      ),
    ),
    Expanded(
      child: RaisedButton(
        child: Text('Reject'),
        onPressed: () => null,
      ),
    ),
    Expanded(
      child: RaisedButton(
        child: Text('Need Revise'),
        onPressed: () => null,
      ),
    )
  ],
);