'Flutter onPressed Function

Error in onPressed Trying to pass onPressed Function but getting Error.

Error - The argument type 'Function' can't be assigned to the parameter type 'void Function()?'. enter image description here

class CircleButton extends StatelessWidget {
  CircleButton({required this.icon, required this.onPressed});
  final IconData icon;
  final Function onPressed;                 [![Error][1]][1]//Here
  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      child: Icon(icon),
      onPressed: onPressed,
      style: ElevatedButton.styleFrom(
        elevation: 6.0,
        primary: Color(0xFF4C4F5E),
        shape: CircleBorder(),
        padding: EdgeInsets.all(15),
      ),);
  }}


Solution 1:[1]

The Function type is actually a dynamic Function type.

The ElevatedButton expects a void Function to its onPressed method, which there is actually a type that is a typedef for it: VoidCallback

So, replace your Function onPressed with VoidCallback onPressed.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Miguel Ruivo