add clear_on_doubleclick prop for clearing clickData

[cpsievert]

No description provided.

[chriddyp]

Only on dragmode='zoom'? Also, could we be more specific about dragmode, like figure['layout']['dragmode'] = 'zoom' or config['dragmode'] = 'zoom'

[chriddyp]

Seems reasonable and a natural extension of the existing API. I would imagine that clear_on_click would be more common / easier to use, why the doubleclick?

Ultimately I really want the plotly.js to make this natural behaviour by adding a click mode to select so that we don't need to program in hacks like this and so that the behaviour is consistent across all contexts (cc @alexcjohnson ), this is being tracked in plotly/plotly.js#1852

[cpsievert]

I would imagine that clear_on_click would be more common / easier to use, why the doubleclick?

By clear_on_click, I assume you mean any click event on the plot? It seems as though that would make it too easy to clear a selection, which would be especially problematic if you want selections to persist. In plotly's shiny integration, I've actually been 'clearing click data' on any double-click event (regardless of dragmode) for quite some time now and haven't really run into issues with it. Note that d00621f clears clickData on "plotly_deselect" events as well now which is consistent with that shiny behavior (and should've been included in the initial PR)

[alexcjohnson]

@chriddyp@cpsievert can we drop this PR now that plotly.js has built-in click-to-select plotly/plotly.js#2944?

[chriddyp]

definitely