Shiny R Input - Add to end of data frame continuously - r

Question

I currently have the following shiny app and the intention is to add the text input as a new row into the dataset. Currently, the new text input is overriding the old input instead of appending to the end. I understand that's happening because I'm referring to df in the eventReactive, which is the originally seeded empty data frame, but my various attempts around that have led to errors.
Does somebody know of a way to fix that? Bonus if there is a way to clear the text input box after hitting the submit button.
library(shiny)
colClasses = c("factor", "numeric")
col.names = c("Player", "1")
df <- read.table(text = "",
colClasses = colClasses,
col.names = col.names)
ui <- fluidPage(
# Application title
titlePanel("Random Draft Order"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
textInput("AddPlayer",
"Add Player",
""),
actionButton("submit", ("Submit"))
),
# Show a plot of the generated distribution
mainPanel(
tableOutput("racingbars")
)
)
)
server <- function(input, output) {
actionButton("submit", ("Submit"))
FinalData = eventReactive(input$submit,{
df = rbind(df, data.frame("Player" = input$AddPlayer, "X1" = ""))
})
output$racingbars <- renderTable({
FinalData()
})
}
# Run the application
shinyApp(ui = ui, server = server)

Answer 1

You could try this creating a reactiveVal that will store the data.
First, you can initialize your data.frame df as a reactiveVal:
df <- reactiveVal(data.frame(Player = character(),
X1 = character()))
To update the reactiveVal you can use:
df(new_dat)
And to reference the data later on, use:
df()
In your example, an observeEvent can be triggered by your submit button. When that happens, you can add your row of data to the reactiveVal data.frame similar to what you have done. The output can then point to the reactiveVal data.frame to display the data.
I also added updateTextInput to the observeEvent to clear the text input after the submit button is pressed. Note this requires session in the server function declaration.
server <- function(input, output, session) {
df <- reactiveVal(data.frame(Player = character(),
X1 = character()))
observeEvent(input$submit, {
new_dat <- rbind(df(), data.frame(Player = input$AddPlayer, X1 = ""))
df(new_dat)
updateTextInput(session, "AddPlayer", value = "")
})
output$racingbars <- renderTable({
df()
})
}