Save reactive table selected from dropdown menu - r

Question

I am new to shiny, I sm trying to save reactive tables based on user selection from a dropdown menu. I would like my dropdown menu to have a list of reactive tables that a user can select then click the save button to save the table selected, this is what I tried but the seems the dropdown doesn't select the reactive tables
# Set libraries
library(shiny)
library(shinyFiles)
# Shiny app with two fields that the user can submit data for
shinyApp(
ui = fluidPage(
DT::dataTableOutput("responses", width = 300), tags$hr(),
selectInput("data", "data:",
choices=(df1(),df2())),
tags$hr(),
shinySaveButton("save", "Save file", "Save file as ...", filetype="csv")
#actionButton("submit", "Submit")
),
server = function(input, output, session) {
#create dataframe one
df1<- reactive({
df <- data.frame("id" = 1:2, "Age" = c(21,15), "Name" = c("John","Dora"))
df
})
#create dataframe two
df2<- reactive({
df <- data.frame("id" = 2:4, "Age" = c(521,715), "Name" = c("Hellen","Jane"))
df
})
##########################################
observeEvent(input$save,{
volumes <- c("UserFolder"="path")
shinyFileSave(input, "save", roots=volumes, session=session)
fileinfo <- parseSavePath(volumes, input$save)
data <- input$data
if (nrow(fileinfo) > 0) {
write.csv(data, as.character(fileinfo$datapath))
}
})
})
My end result should be an app where a user selects a reactive table to save from dropdown then go ahead and click save button. The reason I opted for this option is that I have more reactive tables generated in the app that I would like to save each on its own directory.

Answer 1

Let me know if this is what you're looking for.
I set the selectInput to list 2 strings as default data frames to be downloaded:
selectInput("data", "data:", choices=c("df1", "df2"))
This can be dynamically updated with updateSelectInput as mentioned in comments.
You can have one reactive variable to determine what data to view and save df. output$responses will show the table. Both this function and the observeEvent will call df to get data, and df will provide the relevant data frame based on whatever the selectInput is set to.
# Set libraries
library(shiny)
library(shinyFiles)
library(DT)
# Shiny app with two fields that the user can submit data for
shinyApp(
ui = fluidPage(
dataTableOutput("responses", width = 300),
tags$hr(),
selectInput("data", "data:", choices=c("df1", "df2")),
tags$hr(),
shinySaveButton("save", "Save file", "Save file as ...", filetype="csv")
#actionButton("submit", "Submit")
),
server = function(input, output, session) {
#data will contain selected dataframe
df <- reactive({
switch (input$data,
"df1" = data.frame("id" = 1:2, "Age" = c(21,15), "Name" = c("John","Dora")),
"df2" = data.frame("id" = 3:4, "Age" = c(521,715), "Name" = c("Hellen","Jane"))
)
})
#show selected data in data table
output$responses <- renderDataTable({
df()
})
##########################################
observeEvent(input$save,{
volumes <- c("UserFolder"="path")
shinyFileSave(input, "save", roots=volumes, session=session)
fileinfo <- parseSavePath(volumes, input$save)
data <- df()
if (nrow(fileinfo) > 0) {
write.csv(data, as.character(fileinfo$datapath))
}
})
})