Feature request: Change HTMLWidgets.shinyMode to integers 0, 1, 2...

[dipterix]

Recently I was trying to render the htmlwidgets in rmarkdown with shinyrmd runtime, but then I encountered rendering errors.

The reason is because when rendered in shinyrmd or shiny_prerendered runtime, Shiny has invalid onInputChanged method. This will invalidate many widgets that are expecting this feature, for example, visNetwork and threeBrain, etc. are expecting to communicate with shiny, which will definitely fail.

Please see more details from this issue: rstudio/rmarkdown#2232

I was wondering if HTMLWidgets.shinyMode could be integers such that:

• HTMLWidgets.shinyMode=0 means no shiny is detected
• HTMLWidgets.shinyMode=1 means shiny is detected and is in normal dashboard mode or shiny runtime in rmarkdowns
• HTMLWidgets.shinyMode=2 means shiny is detected but rendered in rmarkdown with shinyrmd or shiny_prerendered runtime

If this change could break many packages, when maybe add HTMLWidgets.runtimeMode?