track abstract method
Returns a stream of bounding client rectangles for element
.
NOTE: The first event is not guaranteed to happen in the same VM turn. To obtain a first response without waiting, use measure.
The stream is automatically deduped, and an updated scheduled whenever the DOM may have re-flowed (see DomService.onLayoutChanged). This is an expensive operation and should be limited to active elements.
Throws StateError if element
is not within the live DOM.
Implementation
Stream<Rectangle> track(Element element, {bool aways = false});