r - Shiny :如果 radioButtions() 为空/未选中​​，actionButton() 能否返回错误？

Question

我还没有找到我的问题的解决方案，这个 SO thread接近但不完全。

我制作了一个简单的应用，其中包含几个radioButtons()。符合 app 基本概念的逻辑，其中一些是空的，如 radioButtons( ... , selected=character(0)) 而另一些具有预选值。

重要的是，在 actionButton() 开始进一步分析之前，所有 radioButtons() 都必须有一个选定的值。

问题:如何设计一个 actionButton()，它 (1) 在未选择 radioButtons() 的情况下返回错误和 (2) 返回包含未选择值的 radioButtons()，特别是？

预期输出

写着

library(shiny)
library(shinyjs)
library(shinycustomloader)
library(shinyWidgets)



ui <- fluidPage(

  useShinyjs(),


  tabsetPanel(

    # GTR
    tabPanel(title = HTML(paste(h4("Gross Total Resection"),
                                h6("Simpson Grade I-III", align = "left"))),
             br(), br(),

             fluidRow(

               column(
                 4,
                 wellPanel(
                   style = "height:275px",
                   h4("Patient-related factors", align="center"), br(),
                   sliderInput("GTR_age", "Age", 
                               min = 18, max = 100, value = 60), br(), 

                   radioButtons("GTR_sex", "Sex", choiceValues=list("Male","Female"),
                                choiceNames=list("Male","Female"), selected=character(0), inline = T)
                 ), br(), br(),

                 fluidRow(align="center", br(), actionBttn("GTRdo", "Submit", style = "material-flat"))
               ),


               column(
                 4,
                 wellPanel(
                   style = "height:375px", 
                   h4("Tumor-related factors", align="center"), br(),

                   radioButtons("GTR_WHO", "WHO Grade", choiceValues=list("WHO-I","WHO-II", "WHO-III"),
                                choiceNames=list("WHO-I","WHO-II","WHO-III"), selected=character(0), inline=T), br(),

                   sliderInput("GTR_Ki67", "Ki-67 proliferative index", 
                               min = 0, max = 60, value = 5), br(),

                   selectInput("GTR_location", "Location",
                               c("Convexity" = "0",
                                 "Parasagittal" = "1",
                                 "Anterior skull-base" = "2",
                                 "Mid skull-base" = "3",
                                 "Posterior skull-base" = "4"))
                 )),


                 column(
                   4,
                   wellPanel(
                     style = "height:525px", 
                     h4("Treatment-related factors", align="center"), br(),

                     radioButtons("GTR_Simpson", "Simpson Grade", choiceValues=list("Grade I","Grade II", "Grade III"),
                                  choiceNames=list("Grade I","Grade II","Grade III"), selected=character(0), inline=T), br(),

                     radioButtons("GTR_EXBR", "External Beam Radiation", choiceValues=list("No","Yes"),
                                  choiceNames=list("No","Yes"), selected ="No", inline=T),
                     sliderInput("GTR_EXBRGy", "Cumulative Gy",
                                  min = 40, max = 60, value = 54.2, step = 0.2), br(),

                     radioButtons("GTR_SRS", "Stereotactic radiosurgery", choiceValues=list("No","Yes"),
                                  choiceNames=list("No","Yes"), selected ="No", inline=T),
                     sliderInput("GTR_SRSGy", "Cumulative Gy",
                                  min = 12, max = 22, value = 15, step = 1), br(),

                   )
                 )

               )
             )
    )
  )

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


  GTR_rvs <- reactiveValues(prev_value = 54.2)

  observeEvent(input$GTR_EXBR, {
    if(input$GTR_EXBR == "No"){
      updateSliderInput(session, "GTR_EXBRGy",min = 0, max = 0, value=0)
      GTR_rvs$prev_value <- input$GTR_EXBRGy
      disable("GTR_EXBRGy")
    }else{
      updateSliderInput(session, "GTR_EXBRGy",  min = 40, max = 60, value = GTR_rvs$prev_value)
      enable("GTR_EXBRGy")
    }
  })

  observeEvent(input$GTR_EXBRGy, {
    print(input$GTR_EXBRGy)
  })



  GTR_rvs_srs <- reactiveValues(prev_value = 15)

  observeEvent(input$GTR_SRS, {
    if(input$GTR_SRS == "No"){
      updateSliderInput(session, "GTR_SRSGy",min = 0, max = 0, value=0)
      GTR_rvs_srs$prev_value <- input$GTR_SRSGy
      disable("GTR_SRSGy")
    }else{
      updateSliderInput(session, "GTR_SRSGy",  min = 12, max = 22, value = GTR_rvs_srs$prev_value)
      enable("GTR_SRSGy")
    }
  })

  observeEvent(input$GTR_SRSGy, {
    print(input$GTR_SRSGy)
  })






}

shinyApp(ui, server)

Answer 1

这应该给你你想要的。它使用以下技术:

• renderUI() 显示错误信息，带格式
• req() 检查是否应该显示红色错误信息
• toggleState() 使“提交”按钮仅在所有指定单选按钮的长度都不为 0 时才可单击(由 character(0)

library(shiny)
library(shinyjs)
library(shinycustomloader)
library(shinyWidgets)



ui <- fluidPage(

  useShinyjs(),


  tabsetPanel(

    # GTR
    tabPanel(title = HTML(paste(h4("Gross Total Resection"),
                                h6("Simpson Grade I-III", align = "left"))),
             br(), br(),

             fluidRow(

               column(
                 4,
                 wellPanel(
                   style = "height:275px",
                   h4("Patient-related factors", align="center"), br(),
                   sliderInput("GTR_age", "Age", 
                               min = 18, max = 100, value = 60), br(), 

                   radioButtons("GTR_sex", "Sex", choiceValues=list("Male","Female"),
                                choiceNames=list("Male","Female"), selected=character(0), inline = T)
                 ), br(), br(),

                 fluidRow(align="center", br(), actionBttn("GTRdo", "Submit", style = "material-flat"),br(),
                          uiOutput("req_text", style = "width: 200px; color: red"))
               ),


               column(
                 4,
                 wellPanel(
                   style = "height:375px", 
                   h4("Tumor-related factors", align="center"), br(),

                   radioButtons("GTR_WHO", "WHO Grade", choiceValues=list("WHO-I","WHO-II", "WHO-III"),
                                choiceNames=list("WHO-I","WHO-II","WHO-III"), selected=character(0), inline=T), br(),

                   sliderInput("GTR_Ki67", "Ki-67 proliferative index", 
                               min = 0, max = 60, value = 5), br(),

                   selectInput("GTR_location", "Location",
                               c("Convexity" = "0",
                                 "Parasagittal" = "1",
                                 "Anterior skull-base" = "2",
                                 "Mid skull-base" = "3",
                                 "Posterior skull-base" = "4"))
                 )),


               column(
                 4,
                 wellPanel(
                   style = "height:525px", 
                   h4("Treatment-related factors", align="center"), br(),

                   radioButtons("GTR_Simpson", "Simpson Grade", choiceValues=list("Grade I","Grade II", "Grade III"),
                                choiceNames=list("Grade I","Grade II","Grade III"), selected=character(0), inline=T), br(),

                   radioButtons("GTR_EXBR", "External Beam Radiation", choiceValues=list("No","Yes"),
                                choiceNames=list("No","Yes"), selected ="No", inline=T),
                   sliderInput("GTR_EXBRGy", "Cumulative Gy",
                               min = 40, max = 60, value = 54.2, step = 0.2), br(),

                   radioButtons("GTR_SRS", "Stereotactic radiosurgery", choiceValues=list("No","Yes"),
                                choiceNames=list("No","Yes"), selected ="No", inline=T),
                   sliderInput("GTR_SRSGy", "Cumulative Gy",
                               min = 12, max = 22, value = 15, step = 1), br(),

                 )
               )

             )
    )
  )
)

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


  GTR_rvs <- reactiveValues(prev_value = 54.2)

  observeEvent(input$GTR_EXBR, {
    if(input$GTR_EXBR == "No"){
      updateSliderInput(session, "GTR_EXBRGy",min = 0, max = 0, value=0)
      GTR_rvs$prev_value <- input$GTR_EXBRGy
      disable("GTR_EXBRGy")
    }else{
      updateSliderInput(session, "GTR_EXBRGy",  min = 40, max = 60, value = GTR_rvs$prev_value)
      enable("GTR_EXBRGy")
    }
  })

  observeEvent(input$GTR_EXBRGy, {
    print(input$GTR_EXBRGy)
  })



  GTR_rvs_srs <- reactiveValues(prev_value = 15)

  observeEvent(input$GTR_SRS, {
    if(input$GTR_SRS == "No"){
      updateSliderInput(session, "GTR_SRSGy",min = 0, max = 0, value=0)
      GTR_rvs_srs$prev_value <- input$GTR_SRSGy
      disable("GTR_SRSGy")
    }else{
      updateSliderInput(session, "GTR_SRSGy",  min = 12, max = 22, value = GTR_rvs_srs$prev_value)
      enable("GTR_SRSGy")
    }
  })

  observeEvent(input$GTR_SRSGy, {
    print(input$GTR_SRSGy)
  })

  observe({
    toggleState(id = "GTRdo", condition = length(input$GTR_sex) > 0 &
                  length(input$GTR_WHO) > 0 &
                  length(input$GTR_Simpson) > 0)
  })

  output$req_text <- renderUI({
    req(length(input$GTR_sex) == 0 |
        length(input$GTR_WHO) == 0 |
        length(input$GTR_Simpson) == 0)

    out <- tagList(p("Please choose:"),
                   tags$ul(style = "text-align: left"))

    if(length(input$GTR_sex) == 0) {
      out[[2]] <- tagAppendChild(out[[2]],tags$li("Sex"))
    }
    if(length(input$GTR_WHO) == 0) {
      out[[2]] <- tagAppendChild(out[[2]],tags$li("WHO Grade"))
    }
    if(length(input$GTR_Simpson) == 0) {
      out[[2]] <- tagAppendChild(out[[2]],tags$li("Simpson Grade"))
    }
    out

  })


}

shinyApp(ui, server)