The FloatingActionButton widget in Flutter is a circular button typically placed in the bottom-right corner of the screen. It's commonly used to trigger the most important action in the application, such as adding a new item or navigating to a primary destination.

Attributes:

1. onPressed (Function):

   • The callback function that is called when the button is pressed. This attribute is required.

2. child (Widget):

   • The widget to be displayed inside the button. It's typically an Icon or Text widget.

3. tooltip (String):

   • The tooltip message to be displayed when the user long-presses the button. It's an optional attribute.

4. backgroundColor (Color):

   • The background color of the button. It defaults to the accent color of the current theme if not specified.

5. foregroundColor (Color):

   • The foreground color of the button, which affects the color of the child widget. It defaults to white if not specified.

6. elevation (double):

   • The elevation of the button, which affects its shadow. The default value is 6.0.

7. shape (ShapeBorder):

   • The shape of the button. It defaults to a circular shape.

8. heroTag (Object):

   • An optional tag for identifying the button in hero animations. If omitted, a unique tag will be generated automatically.

Example:

import 'package:flutter/material.dart';

class FloatingActionButtonExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('FloatingActionButton Widget Example'),
      ),
      body: Center(
        child: Text('Press the FloatingActionButton'),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          // Add your action here
          print('FloatingActionButton pressed');
        },
        child: Icon(Icons.add),
        tooltip: 'Add',
        backgroundColor: Colors.blue,
      ),
    );
  }
}

void main() {
  runApp(MaterialApp(
    home: FloatingActionButtonExample(),
  ));
}

Explanation:

• In this example, a FloatingActionButton widget is placed inside a Scaffold widget.

• The onPressed attribute is set to a callback function that prints a message when the button is pressed.

• The child attribute is set to an Icon widget with the "add" icon to represent the button.

• The tooltip attribute is set to "Add" to provide a tooltip message when the button is long-pressed.

• The backgroundColor attribute is set to Colors.blue to specify the background color of the button.

• When you run this code, you'll see an app bar with a title and a centered text widget. Pressing the floating action button will print a message to the console.