I have the following sample flexdashboard:
---
title: "Hover"
output:
flexdashboard::flex_dashboard:
orientation: columns
vertical_layout: fill
runtime: shiny
---
```{r setup, include=FALSE}
library(flexdashboard)
library(tidyverse)
data(iris)
Column {data-width=650}
-----------------------------------------------------------------------
### Chart A
```{r}
iris %>% group_by(Species) %>%
summarise(mean = mean(Sepal.Length)) %>%
ggplot(aes(Species, mean)) + geom_col()
What I want is a tooltip when hovering over the bars in the plot and show its values. I read this article in SO How do I show the y value on tooltip while hover in ggplot2 but it works for Shiny. I tried this:
p <- iris %>% group_by(Species) %>%
summarise(mean = mean(Sepal.Length))
labels <- sprintf("<strong>%s</strong><br/>Mean: %f",
p$Species, p$mean) %>%
lapply(htmltools::HTML)
p %>% ggplot(aes(Species, mean)) + geom_col() + geom_text(aes(label = labels))
This creates an html tool with the specie and value, what I don't have is the hover (plot_hover maybe?) to show the tooltip.
Any help will be greatly appreciated
Regards,
Here is a way. You have to target the top center of a bar to get the tooltip.
---
title: "Untitled"
runtime: shiny
output:
flexdashboard::flex_dashboard:
orientation: columns
vertical_layout: fill
---
```{r setup, include=FALSE}
library(flexdashboard)
library(dplyr)
library(ggplot2)
library(shiny)
```
Column {data-width=650}
-----------------------------------------------------------------------
### Chart A
```{r}
dat <- iris %>% group_by(Species) %>%
summarise(mean = mean(Sepal.Length))
output[["ggplot"]] <- renderPlot({
dat %>%
ggplot(aes(Species, mean)) + geom_col()
})
output[["hoverinfo"]] <- renderUI({
hover <- input[["plot_hover"]]
if(is.null(hover)) return(NULL)
point <- nearPoints(dat, hover, threshold = 50, maxpoints = 1)
if(nrow(point) == 0) return(NULL)
left_px <- hover$coords_css$x
top_px <- hover$coords_css$y
style <-
paste0("position:absolute; z-index:100; background-color: rgba(245, 245, 245, 0.85); ",
"left:", left_px,
"px; top:", top_px, "px;")
# tooltip created as wellPanel
tooltip <- paste0(
"<b> Species: </b>", point[["Species"]], "<br/>",
"<b> mean: </b>", point[["mean"]]
)
wellPanel(
style = style, p(HTML(tooltip))
)
})
plotOutput("ggplot", hover = hoverOpts("plot_hover"))
div(uiOutput("hoverinfo"), style = "pointer-events: none;")
```