Collect All user inputs throughout the Shiny App - r

Question

Is there a way to show the value from textInput() elsewhere in the UI without having to go through server.R with something very verbose like the following?
ui.R
library(shiny)
shinyUI(
fluidPage(
textInput('text_in', label = 'Write text here'),
# elsewhere in the UI...
textOutput('text_out')
))
server.R
library(shiny)
shinyServer(function(input, output) {
output$text_out = renderText(input$text_in)
})
It's not too bad for this example, but it becomes very verbose when I need to do it many times. My desire is to collect all the inputs the user enters throughout the app and compile them into a nice table at the end so they can confirm everything is laid out right.
I've seen you can reference input elements without going through the server when using a JavaScript expression in conditionalPanel() but I'm not sure how to implement that outside of this specific instance.

Answer 1

For accessing all inputs, you can use reactiveValuesToList server-side. You can access input values via Javascript Events like below (I have taken the example from #Pork Chop) :
library(shiny)
ui <- basicPage(
fluidRow(
column(
width = 6,
textInput('a', 'Text A',"a1"),
textInput('b', 'Text B',"b1"),
textInput('c', 'Text A',"c1"),
textInput('d', 'Text B',"d1"),
textInput('e', 'Text A',"e1"),
textInput('f', 'Text B',"f1")
),
column(
width = 6,
tags$p("Text A :", tags$span(id = "valueA", "")),
tags$script(
"$(document).on('shiny:inputchanged', function(event) {
if (event.name === 'a') {
$('#valueA').text(event.value);
}
});
"
),
tableOutput('show_inputs')
)
)
)
server <- shinyServer(function(input, output, session){
AllInputs <- reactive({
x <- reactiveValuesToList(input)
data.frame(
names = names(x),
values = unlist(x, use.names = FALSE)
)
})
output$show_inputs <- renderTable({
AllInputs()
})
})
shinyApp(ui = ui, server = server)

Answer 2

Since your overall objective is to collect all the user inputs and then compile them into a table I will show you how to achieve that with example below. As you can see all of the input variables can be accessed by names from server. I kept them in a reactive just in case you need it for further analysis or for some renderUI functionality.
#rm(list=ls())
library(shiny)
ui <- basicPage(
textInput('a', 'Text A',"a1"),
textInput('b', 'Text B',"b1"),
textInput('c', 'Text A',"c1"),
textInput('d', 'Text B',"d1"),
textInput('e', 'Text A',"e1"),
textInput('f', 'Text B',"f1"),
tableOutput('show_inputs')
)
server <- shinyServer(function(input, output, session){
AllInputs <- reactive({
myvalues <- NULL
for(i in 1:length(names(input))){
myvalues <- as.data.frame(rbind(myvalues,(cbind(names(input)[i],input[[names(input)[i]]]))))
}
names(myvalues) <- c("User Input","Last Value")
myvalues
})
output$show_inputs <- renderTable({
AllInputs()
})
})
shinyApp(ui = ui, server = server)

Answer 3

If the Shiny inputs all have different lengths and the above does not work (e.g. if you have combination of radio buttons, checkboxgroup, textInput, etc.) this will work and can produce a table of variable:value that you can parse later:
AllInputs <- reactive({
myvalues <- NULL
newvalues <- NULL
for(i in 1:length(names(input))){
newvalues <- paste(names(input)[i], input[[names(input)[i]]], sep=":")
myvalues <- append(myvalues, newvalues)
}
myvalues
})
output$show_inputs <- renderTable({
AllInputs()
})

Answer 4

Borrowing from both Pork Chop and mysteRious, here's a solution that works for multiple types of text & number inputs in shiny.
library(shiny)
AdvRchp3 <- "While you’ve probably already used many (if not all)
of the different types of vectors, you may not have thought
deeply about how they’re interrelated. In this chapter,
I won’t cover individual vectors types in too much detail,
but I will show you how all the types fit together as a whole.
If you need more details, you can find them in R’s documentation."
ui <- fluidPage(
fluidRow(
h4("Text Inputs"),
textInput("text_input", "Input some Text", value = "some text"),
passwordInput("password_input", "Input a Password", value = "1234"),
textAreaInput("text_area_input", "Input lots of Text", rows = 3, value = AdvRchp3)
),
fluidRow(
h4("Numeric Inputs"),
numericInput("numeric_input", "Number 1", value = 1, min = 0, max = 100),
sliderInput("slider_input_single", "Number 50", value = 50, min = 0, max = 100),
sliderInput("slider_input_ranges", "Range 10 to 20", value = c(10, 20), min = 0, max = 100)
),
fluidRow(
tableOutput("show_inputs")
)
)
server <- function(input, output, session) {
all_inputs <- reactive({
input_df <- NULL
df_row <- NULL
for(i in 1:length(names(input))){
df_row <- as.data.frame(cbind(names(input)[i], input[[names(input)[i]]]))
input_df <- as.data.frame(dplyr::bind_rows(input_df, df_row))
}
names(input_df) <- c("input_id", "input_val")
input_df
})
output$show_inputs <- renderTable({
all_inputs()
})
}
shinyApp(ui, server)
notice: the rbind is now dplyr::bind_rows, but plyr::rbind.fill will also work.