Using Align widget in the Stack widget without it expanding - flutter

Question

I'm trying to create a custom widget and it makes use of the Stack widget. When I wrap the Stack's children using the Positined widget, the stack hugs the children that are not positioned. When I try to use the Align widget for more precise placement the stack expands to fill all the available space.
I'm trying to avoid using any widget with a fixed size, i.e. Container or SizedBox, as the parent for the Stack widget.
Is there a way to prevent the stack from filling all the available space or work around this that archives the same result?
I'm trying to position a child to the top center of the Stack as an example and this is where I am right now:
Using the Positined widget (I have to try multiple time to get the center position and sometimes its still off):
Positioned(
top: 0,
left: 80,
child: child,
);
Using the Align widget:
Align(
alignment: Alignment.topCenter,
child: child,
);
This should be the result using the Align widget:
Align(
alignment: Alignment.topCenter,
child: child,
);

Answer 1

You can set Stack's alignment to topCenter, Try this:
Stack(
alignment: Alignment.topCenter, // <=== add this
children: [
Container(
color: Colors.grey,
padding: const EdgeInsets.all(8.0),
child: Row(
mainAxisSize: MainAxisSize.min, // <=== add this
children: [
Container(
color: Colors.amber,
height: 30,
width: 30,
),
Container(
color: Colors.green,
height: 30,
width: 30,
),
Container(
color: Colors.blue,
height: 30,
width: 30,
),
Container(
color: Colors.yellow,
height: 30,
width: 30,
),
],
),
),
Container(
color: Colors.red,
height: 30,
width: 30,
)
],
)
Note: make sure you set Row's mainAxisSize to min.