How to Insert selectInput across the datatable

Question

I’m using the Shiny.
How can I display a selectInput, with options from 1 to 5, in all cells of a DT::datatable?

All I’m getting is the tag div, through the vlr[i] within the for.

library(shiny)  
library(DT)  

ui <- fluidPage(  
   DT::dataTableOutput("tbl")  
)  

server <- function(input, output, session) {  

output$tbl <- DT::renderDataTable(  
    options = list(pageLength = 25), {
    n_rows <- c(1:15)
    n_cols <- c(1:10)

    vlr <- c()  
    n_elem <- (length(n_rows)*length(n_cols))  
    for(i in 1:n_elem){  
       #vlr_of_cc[i] = paste("vlr",i,sep = "_")  
        vlr[i] <- selectInput(paste("vlr",i,sep = "_"), label = NULL, c(0:5), selected = "0")  
    }  

    df <- as.data.frame(matrix(vlr, nrow = 15, ncol = 10, byrow = T, dimnames = list(n_rows, n_cols)))  
})  
}  

shinyApp(ui, server)  

thank you.

Answer 1

Initially I would like to point out that the example you put forth generates a datatable STATIC. So, even if you were able to replace yours with a type of HTML entry, whether it’s a button or a list select, STILL, you’d have to find a way to send this data to Shiny.

EXCHANGING INPUT WITH Datatable

I took the example that you quoted and I switched to a list instead of radiobutton. Here is an example of code that swaps the input for a list:

library(shiny)  
library(DT)  

shinyApp(
  ui = fluidPage(
    title = 'Radio buttons in a table',
    DT::dataTableOutput('foo'),
    verbatimTextOutput('sel')
  ),
  server = function(input, output, session) {
    m = matrix(
      as.character(1:5), nrow = 12, ncol = 5, byrow = TRUE,
      dimnames = list(month.abb, LETTERS[1:5])
    )
    for (i in seq_len(nrow(m))) {
      m[i, ] = sprintf(
        '<select name="%s">
          <option value="volvo">Volvo</option>
          <option value="saab">Saab</option>
          <option value="fiat">Fiat</option>
          <option value="audi">Audi</option>
          </select>',
        month.abb[i], m[i, ]
      )
    }
    m
    output$foo = DT::renderDataTable(
      m, escape = FALSE, selection = 'none', server = FALSE,
      options = list(dom = 't', paging = FALSE, ordering = FALSE),
      callback = JS("table.cells().every(function(i, tab, cell) {
          var $this = $(this.node());
          $this.attr('id', this.data());
          $this.addClass('shiny-input-container');
        });
        Shiny.unbindAll(table.table().node());
        Shiny.bindAll(table.table().node());")
    )
    output$sel = renderPrint({
      sapply(month.abb, function(i) input[[i]])
    })
  }
)

This will generate an app like this:

the problem is that with this code it is only possible to take the examples of the list in the first column. I didn’t find an easy way to get element by element from table. And also note that this table in the example you mentioned had a function to return ONLY ONE NUMBER PER LINE. I would have to think better how to access the datatable cells within Shiny.

WORKAROUND

I believe that for the problem you want to solve there is another package that is IDEAL. This package is the rhandsontable. See an example of a table generated by it:

The code that generated this table was this:

DF = data.frame(integer = 1:10,
                numeric = rnorm(10),
                logical = rep(TRUE, 10), 
                character = LETTERS[1:10],
                factor = factor(letters[1:10], levels = letters[10:1], 
                                ordered = TRUE),
                factor_allow = factor(letters[1:10], levels = letters[10:1], 
                                      ordered = TRUE),
                date = seq(from = Sys.Date(), by = "days", length.out = 10),
                stringsAsFactors = FALSE)

rhandsontable(DF, width = 600, height = 300) %>%
  hot_col("factor_allow", allowInvalid = TRUE)

The great advantage is that this package was made to generate a table for data collection and user interaction. Datatable is great for displaying data and allowing filtering, but is not the appropriate tool for this type of interaction.

Finally, I would like to point out that this table is only the frontend, you will still need a method to export this data to the Shiny server. See the documentation package to know how to do this.