R DT package button to download files does not include display tables - r

Question

Here is the simple example.
Suppose I am looking at the table, and I want to download the table excluding the Sepal.Length column.
What should I do? I try to toggle the Sepal.Length column out, and click on excel, but it stills gives me the whole data. I don't want it. Is there any way that I can manipulate this?
Maybe I am not familiar with how it operates in the backend, after I use row reorder extension, or search/filter tables, then the downloaded files is what table displays. So I want something similar when I hide the columns.
This is useful when I have too many columns in a table and sometimes I do not need all of them.
library(shiny)
shinyApp(
ui = fluidPage(DT::dataTableOutput('tbl')),
server = function(input, output) {
output$tbl = DT::renderDataTable(
iris, extensions = "Buttons",
options = list(dom = "Blfrtip",
buttons = list('copy', 'excel', 'print', 'colvis'))
)
}
)
I really appreciate your help.

Answer 1

You can use input$tbl_columns_selected and input$tbl_rows_selected
Here you can select rows and columns (NB : to select column click on the label below the DT)
If you want a selection only on columns then remove input$tbl_rows_selected and set target = 'column' only
library(shiny)
library(xlsx)
library(DT)
shinyApp(
ui = fluidPage(
DT::dataTableOutput('tbl')
,downloadButton("downloadData",label ="Download")
),
server = function(input, output) {
output$tbl = DT::renderDataTable(iris, selection = list(target = 'row+column'))
myFilteredData <- reactive({
df <- iris[input$tbl_rows_selected, input$tbl_columns_selected]
if (length(input$tbl_columns_selected) == 1) {
df <- as.data.frame(df)
colnames(df) <- colnames(iris)[input$tbl_columns_selected]
}
df
})
output$downloadData <- downloadHandler(
filename = function() {paste("test.xlsx")},
content = function(file) {
write.xlsx(myFilteredData(),file, row.names=FALSE)
})
}
)