GGPLOT - print.ggplot

Print by drawing a plot inside a function or for loop and then convert them with ggplotly.

colours <- list(~class, ~drv, ~fl)
p <-    
 # Doesn't seem to do anything!
for (colour in colours) {
  ggplot(mpg, aes_(~ displ, ~ hwy, colour = colour)) +
    geom_point()
}

plotly::ggplotly(p)

## Error in UseMethod("api_create"): no applicable method for 'api_create' applied to an object of class "shiny.tag"

colours <- list(~class, ~drv, ~fl)
p <-    
 # Works when we explicitly print the plots
for (colour in colours) {
  print(ggplot(mpg, aes_(~ displ, ~ hwy, colour = colour)) +
    geom_point())
}

plotly::ggplotly(p)

## Error in UseMethod("api_create"): no applicable method for 'api_create' applied to an object of class "shiny.tag"