partial bar highlight does not work on `geom_bar()` or `geom_hist()` converted with `ggplotly()`

A highlighted plotly "histogram" can have its bars partially highlighted (with best results achieved with the "overlay" barmode), but an equivalent ggplot2 object converted with ggplotly() can't.

This reproducible example showcases all three options. One can drag a rectangle around some points to see that only the pure plotly visualisation gets bar overlays. A bar will only be completely highlighted if all the cases for that bar are selected in the scatterplot.

library(ggplot2)
library(plotly)
# set up highlightable dataset
msleep_h <- highlight_key(msleep)
# scatterplot
gg_point <- (ggplot(msleep_h, aes(x = sleep_total, y = sleep_rem)) +
  geom_point()) %>% 
  ggplotly()
# ggplot2 bar chart does a count
gg_bar <- (ggplot(msleep_h, aes(x = conservation)) +
  geom_bar()) %>% 
  ggplotly() %>% 
  layout(barmode = "overlay")
# also try a histogram geom, which requires switching to the count stat
gg_hist <- (ggplot(msleep_h, aes(x = conservation)) +
             geom_histogram(stat = "count")) %>% 
  ggplotly() %>% 
  layout(barmode = "overlay")
# plotly equivalent
plt_hist <- plot_ly(msleep_h) %>%
  add_histogram(x = ~conservation) %>%
  layout(barmode = "overlay")
# side by side
subplot(gg_point, gg_bar, gg_hist, plt_hist) %>%
  highlight("plotly_selected")

Commencez par l’exemple R reproductible de l’issue, en particulier les conversions ggplotly() de geom_bar() et geom_histogram(stat = "count"), ainsi que l’appel final à highlight("plotly_selected"). Comparez leur comportement de sélection avec celui de l’histogramme plotly pur utilisant barmode = "overlay" ; le travail est terminé lorsque la sélection d’une partie d’une barre ne superpose que les cas sélectionnés dans les deux graphiques convertis.