Render datatable with sparklines in Shiny - r

Question

I want to include sparklines in a shiny DT. It works fine in the RStudio viewer but in Shiny the sparklines are not rendered. Here is a minimal example.
# dependencies
require(sparkline)
require(DT)
require(shiny)
# create data with sparklines
spark_data <- data.frame(
id = c('spark1', 'spark2'),
spark = c(
spk_chr(values = 1:3, elementId = 'spark1'),
spk_chr(values = 3:1, elementId = 'spark2')
)
)
# render in RStudio viewer (this works)
tbl <- datatable(spark_data, escape = FALSE)
spk_add_deps(tbl)
# render in Shiny (no sparklines rendered in DT)
ui <- fluidPage(
sparklineOutput("test_spark"),
dataTableOutput("tbl")
)
server <- function(input, output) {
# sparkline outside DT (works fine) - also ensures sparkline dependencies are attached
output$test_spark <- renderSparkline(sparkline(1:3))
# sparkline inside DT (does not render)
output$tbl <- renderDataTable(
expr = spark_data,
escape = FALSE
)
}
shinyApp(ui = ui, server = server)

Answer 1

I have modified your code to generate sparklines. I refered to this link to generate the sparklines.
require(sparkline)
require(DT)
require(shiny)
# create data
spark_data1<- data.frame(id = c('spark1', 'spark2'),
spark = c("1,2,3", "3,2,1"))
ui <- fluidPage(
sparklineOutput("test_spark"),
DT::dataTableOutput("tbl")
)
server <- function(input, output) {
line_string <- "type: 'line', lineColor: 'black', fillColor: '#ccc', highlightLineColor: 'orange', highlightSpotColor: 'orange'"
cd <- list(list(targets = 1, render = JS("function(data, type, full){ return '<span class=sparkSamples>' + data + '</span>' }")))
cb = JS(paste0("function (oSettings, json) {\n $('.sparkSamples:not(:has(canvas))').sparkline('html', { ",
line_string, " });\n}"), collapse = "")
output$tbl <- DT::renderDataTable({
dt <- DT::datatable(as.data.frame(spark_data1), rownames = FALSE, options = list(columnDefs = cd,fnDrawCallback = cb))
})
}
shinyApp(ui = ui, server = server)
Hope it helps!

Answer 2

Old-ish question, I know, but based on info in the question Add label to sparkline plot in datatable I think the solution is what you tried originally plus just a few lines. Here I trimmed out the parts demo-ing it works in the viewer and added just what is needed to make the sparklines work.
# dependencies
require(sparkline)
require(DT)
require(shiny)
# create data with sparklines
spark_data <- data.frame(
id = c('spark1', 'spark2'),
spark = c(
spk_chr(values = 1:3, elementId = 'spark1'),
spk_chr(values = 3:1, elementId = 'spark2')
)
)
### adding this <------------
cb <- htmlwidgets::JS('function(){debugger;HTMLWidgets.staticRender();}')
ui <- fluidPage(
### and this <------------
htmlwidgets::getDependency('sparkline'),
dataTableOutput("tbl")
)
server <- function(input, output) {
output$tbl <- renderDataTable(
expr = spark_data,
escape = FALSE,
### and this <------------
options = list(
drawCallback = cb
)
)
}
shinyApp(ui = ui, server = server)