How to embed ggvis interactive charts in RMarkdown?

Question

I am trying to knit an RMarkdown into html this plot from the interactivity vignette:

mtcars %>% ggvis(x = ~wt) %>%
    layer_densities(
      adjust = input_slider(.1, 2, value = 1, step = .1, label = "Bandwidth adjustment"),
      kernel = input_select(
        c("Gaussian" = "gaussian",
          "Epanechnikov" = "epanechnikov",
          "Rectangular" = "rectangular",
          "Triangular" = "triangular",
          "Biweight" = "biweight",
          "Cosine" = "cosine",
          "Optcosine" = "optcosine"),
        label = "Kernel")
    )

But I get the following error message:

## Warning: Can't output dynamic/interactive ggvis plots in a knitr document.
## Generating a static (non-dynamic, non-interactive) version of the plot.

Answer 1

You must set "output: html_document" and "runtime: shiny" in the header. This works for me:

---
title: "stackoverflow"
author: "Kári S Friðriksson"
date: "7 nóvember 2016"
output: html_document
runtime: shiny
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
library(ggvis)
```



```{r eruptions, echo=FALSE}
mtcars %>% ggvis(x = ~wt) %>%
    layer_densities(
      adjust = input_slider(.1, 2, value = 1, step = .1, label = "Bandwidth adjustment"),
      kernel = input_select(
        c("Gaussian" = "gaussian",
          "Epanechnikov" = "epanechnikov",
          "Rectangular" = "rectangular",
          "Triangular" = "triangular",
          "Biweight" = "biweight",
          "Cosine" = "cosine",
          "Optcosine" = "optcosine"),
        label = "Kernel")
    )
```

The easiest way to do this is to go to file/new file/R markdown/Shiny/Shiny document. Then the header will be automatically set up for you, and there will be a play button instead of the knitr button on the bar above the code box. Notice also that you need to include library(ggvis) in the code because shiny will start with a cleas slate and not be able to "see" the packages or functions that you have loaded.