Write data table with text inputs to csv in shiny - r

Question

I have a dataTableOutput that includes a column of textInputs, following the instructions from this question:
Text Input Column in a table in shiny
I modified the code, so that the save button writes the data to a local csv file. However, I'm unable do get the content of the textInput. The column entries contain this kind of information:
<div class="form-group shiny-input-container">
<label class="control-label shiny-label-null" for="cbox_1"></label>
<input id="cbox_1" type="text" class="form-control" value=""/>
</div>
How do I get the actual value of the user input from cbox_1 and the other textInputs? Here is my complete code:
library(shiny)
library(DT)
library(dplyr)
shinyApp(
ui <- fluidPage(DT::dataTableOutput("ruless"),
fluidRow(column(4, offset = 1, actionButton("save", "Save", width = 200),))),
server <- function(input, output) {
values <- reactiveValues(data = NULL)
values$data <- as.data.frame(
cbind(c("a", "d", "b", "c", "e", "f"),
c(1463, 159, 54, 52, 52, 220),
c(0.7315, 0.0795, 0.027, 0.026, 0.026, 0.11)
)
)
shinyInput = function(FUN, len, id, ...) {
#validate(need(character(len)>0,message=paste("")))
inputs = character(len)
for (i in seq_len(len)) {
inputs[i] = as.character(FUN(paste0(id, i), label = NULL, ...))
}
inputs
}
dataExpTable <- reactive({
data.frame(delete=shinyInput(textInput,nrow(values$data),"cbox_"), values$data)
})
output$ruless <- DT::renderDataTable({
datatable(
dataExpTable(),
selection="multiple",
escape = FALSE,
filter = list(position = 'top', clear = FALSE),
extensions = list("ColReorder" = NULL, "Buttons" = NULL),
options = list(
dom = 'BRrltpi',
autoWidth=TRUE,
lengthMenu = list(c(10, 50, -1), c('10', '50', 'All')),
ColReorder = TRUE,
preDrawCallback = JS('function() { Shiny.unbindAll(this.api().table().node()); }'),
drawCallback = JS('function() { Shiny.bindAll(this.api().table().node()); } '),
buttons = list(
'copy',
'print',
list(
extend = 'collection',
buttons = c('csv', 'excel', 'pdf'),
text = 'Download',
selected = TRUE
)
)
)
)
})
observeEvent(input$save, {
write.csv2(dataExpTable(), "test.csv", row.names = FALSE)
})
}
)

Answer 1

A colleauge helped me with the solution. The content of the textInputs can be accessed via the Ids that are created by the shinyInput function. It combines a prefix with the row number of the given data frame. A csv output via the save button could look like this:
observeEvent(
eventExpr = input$save,
handlerExpr = {
out_col <- character(nrow(values$data))
for (i in seq_len(nrow(values$data))) {
out_col[i] <- input[[paste0("cbox_", i)]]
}
out_df <- cbind(out_col, values$data)
write.csv2(out_df, "test.csv", row.names = FALSE)
}
)
I tried a similar approach before, but it did not work. I removed these options when creating the datatable:
preDrawCallback = JS('function() { Shiny.unbindAll(this.api().table().node()); }')
drawCallback = JS('function() { Shiny.bindAll(this.api().table().node()); } ')
However, they are mandatory to access the textInputs via their Ids.