Question

我正在尝试构建一个允许用户从预先提供的列表中选择一个或多个函数（模块）的应用程序，然后根据它们的选择，为该函数的各种参数选择值。

基本上，我正在尝试重构renderUI调用树，以便在发生闪亮的反应部分并调用服务器函数时，如果输入$ abcd.in不为NULL，则使用不同的参数运行renderUI函数取决于输入$ abcd.in的值是什么。

错误似乎是set_output_automatically函数的输入参数长度为0，但我不知道下一步该做什么。

这是一个简化的例子

library(shiny)

arg.info <-  list(
  list(choices = c("Yes" = T, "No" = F),
                  prompt = quote(paste("Remove Missing Values for analysis?")),
                  type = "radioButtons"),
  list(choices = c("not" = 0, "some" = 1, "very" = 3),
       prompt = quote(paste("how cool are you?")),
       type = "checkboxGroupInput"))


set_output_automatically <- function(input, arg.info){

  if(input[1] > 3){
    arg.info <- arg.info[[1]]
  } else {
    arg.info <- arg.info[[2]]
  }

  renderUI({

    call(arg.info$type, paste0(input$abcd, ".in"), label = arg.info$prompt,
         choices = arg.info$choices)
  })


}

ui <- fluidPage(

  uiOutput('abcd'),

  textOutput('value'),

  uiOutput('result')


)

server <- function(input, output){

  output$abcd <- renderUI({

    checkboxGroupInput('abcd.in', 'sample',
                       choices = c('wowe'= 1,
                                   'such' = 2,
                                   'choice' = 3,
                                   'very' = 4,
                                   'programe' = 5))

  })

  output$value <- renderPrint({input$abcd.in})

  output$result <- reactive(set_output_automatically(input$abcd.in, arg.info))

}

shinyApp(ui, server)

Answer 1

我将call替换为do.call（具有参数列表），将renderUI替换为library(shiny) arg.info <- list( list(choices = c("Yes" = T, "No" = F), prompt = quote(paste("Remove Missing Values for analysis?")), type = "radioButtons"), list(choices = c("not" = 0, "some" = 1, "very" = 3), prompt = quote(paste("how cool are you?")), type = "checkboxGroupInput")) set_output_automatically <- function(input, arg.info){ if(input[1] > 3){ arg.info <- arg.info[[1]] } else { arg.info <- arg.info[[2]] } do.call(arg.info$type, args=list(inputId=paste0("in", input), label = arg.info$prompt, choices = arg.info$choices)) } ui <- fluidPage( uiOutput('abcd'), textOutput('value'), uiOutput('result') ) server <- function(input, output){ output$abcd <- renderUI({ checkboxGroupInput('abcd.in', 'sample', choices = c('wowe'= 1, 'such' = 2, 'choice' = 3, 'very' = 4, 'programe' = 5)) }) output$value <- renderPrint({input$abcd.in}) output$result <- renderUI({ set_output_automatically(input$abcd.in, arg.info) }) }，这可行。

{{1}}

R Shiny渲染UI小部件交互式

1 个答案: