constraintsTransform property
The function used to transform the incoming BoxConstraints, to size child.
The function must return a BoxConstraints that is BoxConstraints.isNormalized.
See ConstraintsTransformBox for predefined common BoxConstraintsTransforms.
Implementation
BoxConstraintsTransform get constraintsTransform => _constraintsTransform;
Implementation
set constraintsTransform(BoxConstraintsTransform value) {
if (_constraintsTransform == value) {
return;
}
_constraintsTransform = value;
// The RenderObject only needs layout if the new transform maps the current
// `constraints` to a different value, or the render object has never been
// laid out before.
final bool needsLayout = _childConstraints == null
|| _childConstraints != value(constraints);
if (needsLayout) {
markNeedsLayout();
}
}