Question

我正在尝试编写一个闪亮的应用程序以显示列数据。该代码有效，但在RStudio中得到警告消息。

警告如下：

Warning: Error in [.data.frame: undefined columns selected Stack trace (innermost first): 82: [.data.frame 81: [ 80: print 79: renderTable [/media/ubuntu/C2ACA28AACA27895/Windows/work/R/Shiny_Apps/hos_performance/patsatsys.R#40] 78: func 77: origRenderFunc 76: output$tab1 1: runApp

以下是代码：

library(shiny)
library(shinydashboard)        

ui <- fluidPage(

  navbarPage(title = "PATSATSYS",
             tabPanel("DataSets", 
                      sidebarLayout(
                        sidebarPanel(
                          fileInput("file1", "Choose CSV File", accept=c('text/csv', 'text/comma-separated-values', 'text/plain', '.csv')),
                          selectInput("dcol", "Choose the Column", choices = " ", selected = " ")
                      ), 
                        mainPanel(tableOutput("tab1"))
                    )
         ),
             tabPanel("Discriptives", textOutput("sum-1")),
             tabPanel("Revenue/Cost", textOutput("text-1")),
             tabPanel("Performance", textOutput("text-2"))
         )
  )


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

  data_input <- reactive({
    infile <- input$file1
    req(infile)
    data.frame(read.csv(infile$datapath)) 
  })

  observeEvent(input$file1,{
    updateSelectInput(session,
                  inputId = "dcol",
                  choices = names(data_input()))
  }
  )

  output$tab1 <- renderTable({
    df <- data_input()
    print(df[input$dcol])

  })
}

shinyApp(ui, server)

我希望代码能够执行而不会发出警告消息。如何清除警告消息？

Answer 1

这应该做到：

  output$tab1 <- renderTable({
    data_input()[[input$dcol]]
  })

在闪亮的应用程序中打印基于列的数据时获取警告消息

1 个答案: