反应性地更新两组单选按钮 - 闪亮

Question

我已阅读此 (How do I make the choices in radioButtons reactive in Shiny?)，它向我展示了如何以反应方式更新 radioButtons。但是，当我尝试从同一数据更新两组按钮时，只有一组呈现。示例：

服务器：

# Create example data

Wafer <- rep(c(1:3), each=3)
Length <- c(1,1,2,1,1,1,3,5,1)
Width <- c(3,1,6,1,1,1,1,1,6)

dd <- data.frame(Wafer, Length, Width)

shinyServer(function(input, output, session){

# Create reactive dataframe to store data
  values <- reactiveValues()
  values$df <- data.frame()

# Get Lengths and Widths of wafer from user input
 a <- eventReactive(input$do, {
       subset(dd, Wafer %in% input$wafer, select = Length:Width) 
 })

# Update reactive data frame will all Lengths and Widths that have been selected by the user input

 observe({
   if(!is.null(a())) {
     values$df <- rbind(isolate(values$df), a())
   }
  })

  output$wl <- renderDataTable({ a() })

# Update radio buttons with unique Length and Widths stored in values$df
# Which ever "observe" I put first in the code, is the one which updates 
# the radio buttons. Cut and paste the other way round and "width" 
# updates but not "length" radio buttons

  observe({ 
    z <- values$df
    updateRadioButtons(session, "length", choices = unique(z$Length), inline=TRUE)
  })

  observe({ 
    z <- values$df
    updateRadioButtons(session, "width", choices = unique(z$Width), inline=TRUE)
  })

})

ui:

library(markdown)

shinyUI(fluidPage(
  titlePanel("Generic grapher"),
  sidebarLayout(
    sidebarPanel(

      numericInput("wafer", label = h3("Input wafer ID:"), value = NULL),

      actionButton("do", "Search wafer"),
      radioButtons("length", label="Length", choices=""),
      radioButtons("width", label="Width", choices = "")

    ),

    mainPanel(

      dataTableOutput(outputId="wl")
    )
  )
)
)

在上面，单选按钮会更新，但仅针对代码顺序的第一组按钮，即上面 "length" 更新，但 "width" 不更新。如果我反过来写，"width" 会更新，但 "length" 不会。我是否需要定义一个新会话？

Answer 1

事实证明：

"it's because a JS error occurs if the choices argument isn't a character vector."

我在 Shiny 的 Github 上发布了一个问题：

https://github.com/rstudio/shiny/issues/1093

这可以通过以下方式解决：

To fix your problem, you can either convert your choices to characters using as.character or set selected to a random string such as "".

参见：

反应性地更新两组单选按钮 - 闪亮

Update two sets of radiobuttons reactively - shiny

r

shiny

shiny-reactivity