layoutCallback method
override
Invokes the builder callback supplied via AbstractLayoutBuilder and rebuilds the AbstractLayoutBuilder's widget tree, if needed.
No further work will be done if layoutInfo has not changed since the last
time this method was called, and AbstractLayoutBuilder.updateShouldRebuild
returned false
when the widget was rebuilt.
This method should typically be called as soon as possible in the class's performLayout implementation, before any layout work is done.
Implementation
@visibleForOverriding
@override
void layoutCallback() => _callback!(constraints);