apache
[Feature] Shadow series key
What problem does this feature solve?
To customize a chart, it's convenient to shadow/clone an existing series (e.g. bar) with a custom one, so you can draw on additional shapes (e.g. with silent: true) without having to reinvent the wheel.
But, this new series is disconnected from the original, so it won't toggle on/off when the original series is toggled. Trying to use the same series ID doesn't work.
It would be convenient to be able to define a shadow key/id for use with silent series, so that it would be considered a duplicate of the original.
Or if there is an existing way to do so, to show this more clearly in the examples and docs. e.g. It's unclear to me how to replicate bar series as a custom one. I don't know how to respond to the dynamic state of the legend on/off toggle in renderItem and api.barLayout. It seems to be static and requires passing in e.g. the count and barGap, rather than re-using the same state from bar.
What does the proposed API look like?
A series.shadowId property that can have the id of another series.
Using the same series.name should make different series share a single legend item.
