Make buttons in a row have the same width in flutter

There are two ways:

1. Expanded widget it will divide space in equal parts. If you use all expanded widget for row of column.
2. Get the width of the screen and divide it into the required sizes equally.

Double width = MediaQuery.of(context).size.width;

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,
      ),
    )
  ],
);