clearSemantics method
Removes all semantics from this render object and its descendants.
Should only be called on objects whose parent is not a RenderObject.
Override this method if you instantiate new SemanticsNodes in an overridden assembleSemanticsNode method, to dispose of those nodes.
Implementation
@mustCallSuper
void clearSemantics() {
_needsSemanticsUpdate = true;
_semantics = null;
visitChildren((RenderObject child) {
child.clearSemantics();
});
}