MDC-104 Flutter: Material Advanced Components (Flutter) - Step 4

[msphotosite]

Widget _buildStack() {
child: Stack(
key: _backdropKey,
children: [
widget.backLayer,
widget.frontLayer,
],
);
}

contains an error.

Replace it with:

Widget _buildStack() {
return Stack(
key: _backdropKey,
children: [
widget.backLayer,
widget.frontLayer,
],
);
}

[willlarche]

Thank you! Great catch. I've fixed it there and in the place where we wrap the frontLayer. Let me know if it's not correct still.