<p dir="auto">I observed a developer unable to figure out how to use ListView due to lack of content in the API doc. While the ListView constructor is relatively easy to understand, ListView.builder() and ListView.custom are less so. It would be great to include some sample code in the API doc.</p>
<p dir="auto">I think we need some high level documentation of all the list and viewport classes, including a class hierarchy diagram showing inheritance, mixins, ownership, and who creates whom. It should probably lean on some other documentation explaining the purpose of custom Element subclasses, too.</p>