of static method Null safety

MaterialInkController of(
  1. BuildContext context

The ink controller from the closest instance of Material that encloses the given context.

If no Material widget ancestor can be found then this method will assert in debug mode, and throw an exception in release mode.

Typical usage is as follows:

MaterialInkController inkController = Material.of(context);

This method can be expensive (it walks the element tree).

See also:


static MaterialInkController of(BuildContext context) {
  final MaterialInkController? controller = maybeOf(context);
  assert(() {
    if (controller == null) {
      throw FlutterError(
        'Material.of() was called with a context that does not contain a Material widget.\n'
        'No Material widget ancestor could be found starting from the context that was passed to '
        'Material.of(). This can happen because you are using a widget that looks for a Material '
        'ancestor, but no such ancestor exists.\n'
        'The context used was:\n'
        '  $context',
    return true;
  return controller!;