Adding an Image to a Datatable in R

Adding an image to a datatable in R

This is one way to do it (by embedding base64 encoded images and using that for the src).

First we'll make a small helper:

img_uri <- function(x) { sprintf('<img src="%s"/>', knitr::image_uri(x)) }

That will let us make a data uri. We're slurping up the whole file and converting it to base64 then doing a bit more formatting before sticking the entire blob into the src attribute.

This is what a 1x1 pixel PNG looks like encoded that way:

<img src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEX/TQBcNTh/AAAAAXRSTlPM0jRW/QAAAApJREFUeJxjYgAAAAYAAzY3fKgAAAAASUVORK5CYII=\"/>

So, we just do the same with the one you created:

x = rnorm(1000)   
png(paste0("test.png"))
Plot = plot(x, type = "l")
dev.off()

camino = img_uri("test.png")
data = data.frame(0.5 ,camino)
DT::datatable(data, escape = FALSE)

Yours is having an issue b/c it's not "URI" and it has no way of pulling from the local system. It might work in a browser context with a file://… URL.

How to embed an image in a cell a table using DT, R and Shiny

You can use the escape = FALSE in your DT call, as per: https://rstudio.github.io/DT/#escaping-table-content

# ui.R
require(shiny)
library(DT)

shinyUI(
  DT::dataTableOutput('mytable')
)

# Server.R
library(shiny)
library(DT)

dat <- data.frame(
  country = c('USA', 'China'),
  flag = c('<img src="test.png" height="52"></img>',
           '<img src="http://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Flag_of_the_People%27s_Republic_of_China.svg/200px-Flag_of_the_People%27s_Republic_of_China.svg.png" height="52"></img>'
           )
)

shinyServer(function(input, output){
  output$mytable <- DT::renderDataTable({

    DT::datatable(dat, escape = FALSE) # HERE
  })
})

Want to have a column with images in a datatable; it works with URL but does not work with local paths

Indeed, that doesn't work. This way works, with the images in the www subfolder:

render <- c(
  "function(data, type, row){",
  "  if(type === 'display'){",
  "    var tag = '<img src=\"' + data + '.png\" width=\"100\"/>';",
  "    return tag;",
  "  } else {",
  "    return data;",
  "  }",
  "}"
)

df <- reactiveValues(data = data.frame(
  Name = readUnits$label,
  Icon=c("img1",
         "img1",
         "img2",
         .........),
  Actions = shinyInput(
    actionButton, 12, 'button_', label = "Linked to", onclick = 'Shiny.onInputChange(\"select_button\", this.id)'
  ),
  stringsAsFactors = FALSE,
  row.names = 1:12
))

output$data <- renderDT({
  datatable(
    df$data, 
    selection = 'none',
    options = list(
      columnDefs = list(
        list(targets = 2, render = JS(render))
      )
    )
  )
}, server = FALSE)

Add an image to a table-like output in R

If you are using knitr with the rmarkdown package, it is pretty easy -- just use the Markdown syntax ![]() to include images, e.g.

---
title: "Flags"
author: "Yihui Xie"
date: "2014/08/03"
output: html_document
---

```{r results='asis'}
dat <- data.frame(
  country = c('Canada', 'United Kindom'),
  abbr = c('ca', 'gb'),
  var1 = c(1, 2),
  var2 = rnorm(2)
)
dat$flag <- sprintf('![](http://flagpedia.net/data/flags/mini/%s.png)', dat$abbr)
library(knitr)
kable(dat)
```

If you need LaTeX/PDF output, you have to download these images by yourself. Here is an example:

---
title: "Flags"
author: "Yihui Xie"
date: "2014/08/03"
output: html_document
---

```{r}
dat <- data.frame(
  country = c('Canada', 'United Kindom'),
  abbr = c('ca', 'gb'),
  var1 = c(1, 2),
  var2 = rnorm(2)
)
dat$file <- paste0(dat$abbr, '.png')
dat$link <- paste0('http://flagpedia.net/data/flags/mini/', dat$file)
dat$flag <- sprintf('![](%s)', dat$file)
for (i in seq_len(nrow(dat))) {
  if (!file.exists(dat$file[i])) xfun::download_file(dat$link[i])
}
knitr::kable(dat[, -c(5, 6)])
```

Rendering images in DT table in R Shiny

A little hidden in the Shiny documentation, you will find METHOD 3 that involves supplying the image files inside a www directory (example reference here or in the cheatsheet).

If your folder structure looks as follows

├── image_test_case.R
├── image_test_case_table.csv
├── www/
│   ├── amerikaan.jpg
│   └── tilia.jpg

then you may set the src tag to the image path relative to the www path.

<img src='amerikaan.jpg' height='200'></img>
<img src='tilia.jpg' height='200'></img>

Note that www is used for all sorts of static resources (most common images, javascript and css files).

Embedding an image in a table cell using DT, R and Shiny not working

Your example is incomplete. Does this work?

require(shiny)
library(DT)

ui <- shinyUI(
  DT::dataTableOutput('mytable')
)

dat <- data.frame(
  country = c('USA', 'China'),
  flag = c('<img src="http://flaglane.com/download/american-flag/american-flag-large.png" height="52"></img>',
           '<img src="https://upload.wikimedia.org/wikipedia/commons/2/2e/Flag_of_China.png" height="52"></img>'
  )
)

server <- shinyServer(function(input, output){
  output$mytable <- DT::renderDataTable({
    DT::datatable(dat, escape = FALSE)
  })
})

shinyApp(ui, server)

It works fine for me.

How to save a table I created with (DT), datatable into a high quality image?

You can use the saveWidget function to save the datatable in a html file, then use the webshot package to take a snapshot.

library(DT)
library(webshot)
dtable <- datatable(iris[1:8,])
html <- "dtable.html"
saveWidget(dtable, html)
webshot(html, "dtableSnapshot.png") # you can also export to pdf

---

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