Error ggplotly: VECTOR_ELT() can only be applied to a 'list', not a 'NULL'

Question

I'm using R 3.3.3 and RStudio 1.0.136, and the latest versions of all the packages.

I get this error with the plotly package

> ggiris <- qplot(Petal.Width, Sepal.Length, data = iris, color = Species)
> ggplotly(ggiris)
Error in grid.Call(L_convert, x, as.integer(whatfrom), as.integer(whatto),  : 
  VECTOR_ELT() can only be applied to a 'list', not a 'NULL'

This error does not occur anymore after I "print" the ggplot:

> ggiris
> ggplotly(ggiris)

It occurs not only in RStudio, but also in a Shiny app.

Any hint ?

Note: This more likely occurs with a "fresh" session (just after opening RStudio).

> sessionInfo()
R version 3.3.3 (2017-03-06)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1

locale:
[1] LC_COLLATE=French_Belgium.1252  LC_CTYPE=French_Belgium.1252   
[3] LC_MONETARY=French_Belgium.1252 LC_NUMERIC=C                   
[5] LC_TIME=French_Belgium.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] plotly_4.5.6  ggplot2_2.2.1

loaded via a namespace (and not attached):
 [1] Rcpp_0.12.9       tidyr_0.6.1       viridisLite_0.1.3 digest_0.6.12    
 [5] dplyr_0.5.0       assertthat_0.1    grid_3.3.3        plyr_1.8.4       
 [9] R6_2.2.0          jsonlite_1.3      gtable_0.2.0      DBI_0.6          
[13] magrittr_1.5      scales_0.4.1      httr_1.2.1        lazyeval_0.2.0   
[17] labeling_0.3      tools_3.3.3       htmlwidgets_0.8   purrr_0.2.2      
[21] munsell_0.4.3     yaml_2.1.14       base64enc_0.1-3   colorspace_1.3-2 
[25] htmltools_0.3.5   tibble_1.2       

Answer 1

I am getting the same error when I change characteristics associated with a ggplotly object within a package I am building. Short term fix is to quit and restart the session, as mentioned in a comment above.

Answer 2

I just encountered the same error on my computer, for the same context. I simply update packages from RStudio interface, then I get the error. You probably need to update your R version, it worked for me.

Hope it will help you!