getTransformFrom method
- Selectable child
Gets the paint transform from the Selectable child to SelectionContainer of this delegate.
Returns a matrix that maps the Selectable paint coordinate system to the coordinate system of SelectionContainer.
Can only be called after SelectionContainer is laid out.
Implementation
Matrix4 getTransformFrom(Selectable child) {
assert(
_selectionContainerContext?.findRenderObject() != null,
'getTransformFrom cannot be called before SelectionContainer is laid out.',
);
return child.getTransformTo(_selectionContainerContext!.findRenderObject()! as RenderBox);
}