adding data input into a empty data frame in R using shiny

问题

I am fairly new to shiny and R I am trying to make a user interface for the amount of money used in different companies. I made a empty data frame, and was trying to add the input from the user to the data frame, but the app crashes. Any assistance would be great please!

library(shiny)

df <- data.frame(Company = character(), Goods = character(),GoodsType = character(), 
             Number = integer(), Cost = double(), stringsAsFactors = FALSE)

ui <- fluidPage(
     titlePanel("Cost tool "),

      sidebarLayout(
        sidebarPanel(
          selectInput(inputId = "Company", label = "Company",
                      choices = list("Company 1", "Company 2 " , " Company 3 "), selected = ""),

          radioButtons(inputId = "Goods", label = "Select bought goods",inline = TRUE,
               choices = list("Food", "Electronics","Books"), selected = ""),

          selectInput(inputId = "GoodsType", label = " Types of Goods",
              choices = list(" Milk", "Eggs" , "vegetables" ,"Games Consoles",
               "headphones", "phones", "mystery","fiction","horror"), selected = ""),

          textInput(inputId = "Number", label = " How many?: ",
                    value = ""),

           textInput(inputId = "Cost", label = "Cost",
                    value = ""),

          actionButton("submit","Submit")


  ),
    mainPanel(
     dataTableOutput("CostTable")
    )
  )
)


server <- function(input, output){

 observeEvent(input$submit, {

 df[1,] <- data.frame(input$Company,input$Goods,input$GoodsType, input$Number, input$Cost)


   })


}

shinyApp(ui = ui, server = server)

回答1:

When constructing the dataframe, integers are numeric(). I've also added the reactiveValues so you can put your dataframe into. If you want the dataframe to reset on evey visit you can put v$df <- data.frame(Company =... into the server part of the app

library(shiny)
library(DT)
ui <- fluidPage(
    titlePanel("Cost tool "),
    sidebarLayout(
        sidebarPanel(
            selectInput(inputId = "Company", label = "Company",
                        choices = list("Company 1", "Company 2 " , " Company 3 "), selected = ""),
            radioButtons(inputId = "Goods", label = "Select bought goods",inline = TRUE,
                         choices = list("Food", "Electronics","Books"), selected = ""),
            selectInput(inputId = "GoodsType", label = " Types of Goods",
                        choices = list(" Milk", "Eggs" , "vegetables" ,"Games Consoles",
                                       "headphones", "phones", "mystery","fiction","horror"), selected = ""),
            textInput(inputId = "Number", label = " How many?: ",value = ""),
            textInput(inputId = "Cost", label = "Cost",value = ""),
            actionButton("submit","Submit")
        ),
        mainPanel(
            DT::dataTableOutput("CostTable")
        )
    )
)


v <- reactiveValues()
v$df <- data.frame(Company = character(), Goods = character(),GoodsType = character(), 
                   Number = numeric(), Cost = numeric(), stringsAsFactors = FALSE)

server <- function(input, output, session){

    observeEvent(input$submit,{
        req(input$Company,input$Goods,input$GoodsType,input$Number,input$Cost)
        tmp <- data.frame(Company = input$Company,Goods = input$Goods,GoodsType = input$GoodsType, Number = input$Number,Cost = input$Cost)
        v$df <- rbind(v$df,tmp)
    })
    output$CostTable <- DT::renderDataTable({
        v$df
    })
}

shinyApp(ui = ui, server = server)

来源：https://stackoverflow.com/questions/60733099/adding-data-input-into-a-empty-data-frame-in-r-using-shiny

标签

dataframe

Shiny