rCharts NVD3 custom tooltip

Question

I want to create a scatter plot of the movies dataset where when the user scrolls over a point, it will display the title of the movie. Using the answer from rCharts rNVD3 tooltip customisation, I wrote the following:

movies <- data(movies)
p1 <- nPlot(length ~ votes,
            group = 'mpaa', 
            data = movies, 
            type = 'scatterChart',
            #the following line seems to have NO EFFECT:
            tooltip = "#!function(item){ return item.title + ' ' + '('+item.year+')'}!#")
#item is not a valid input to the tooltipContent function
p1$chart(tooltipContent = "#! function(key, x, y){ 
            return key + ' '+item.year
            } !#")
p1$print("chart3")
p1

As noted in the in-line comments above, neither of these attempts to customize the tooltip is working for me.

Answer 1

You are mixing up tooltip specification for polycharts with nvd3. rCharts is merely a wrapper that lets you access functionalities within these js libraries, and since each library has a different way to let you specify tooltips, things are different. Here is how to make it work

p1$chart(tooltipContent = "#! function(key, x, y, e){ 
  return key + ' ' + e.point.year
} !#")
p1