I am new to flutter and I am trying to make an app, but I got stuck in the initial phase only, and can't figure out what the problem is.
Below is my code:

```
import 'package:flutter/material.dart';

void main() => runApp(BMICalculator());

class BMICalculator extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('BMI CALCULATOR'),
        ),
        body: InputPage(),
      ),
    );
  }
}

class InputPage extends StatefulWidget {
  @override
  _InputPageState createState() => _InputPageState();
}

class _InputPageState extends State<InputPage> {
  @override
  Widget build(BuildContext context) {
    return Center(
      child: Text('Body Text'),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.add),
        onPressed: () {},
      ),
    );
  }
}

```

I am getting error on my floating action button.

Below is the error message:

```
Compiler message:
lib/main.dart:29:7: Error: No named parameter with the name 'floatingActionButton'.
      floatingActionButton: FloatingActionButton(
      ^^^^^^^^^^^^^^^^^^^^
../../../desktop/flutter/flutter/packages/flutter/lib/src/widgets/basic.dart:1870:9: Context: Found this candidate, but the arguments don't match.
  const Center({ Key key, double widthFactor, double heightFactor, Widget child })
        ^^^^^^

```

I need Body text at the centre of the screen and the button at the bottom right corner.