在 R Shiny 中跨多個模塊使用reactiveValues

Question

我正在嘗試在 R 閃亮應用程序中的多個模塊中使用reactiveValues。

我已經建立了一個例子來說明我的問題。 它由一個包含reactiveValue的主應用程序組成，該應用程序是一個包含3列和3個模塊的數據框，旨在“讀取”、“寫入”和“讀取和寫入”reactiveValue。

• 閱讀：應用程序 -> 模塊
• 編寫：模塊 -> 應用程序
• 讀寫：應用程序 <-> 模塊

我收到錯誤：

警告：<- 中的錯誤：“閉包”類型的對象不是可子集的

請注意，如果reactiveValue 只是一個簡單的變量（例如整數），則代碼有效，但不適用於需要更新組件而不是整個數據幀的數據幀。

我發現以下鏈接非常有用。 不確定它是否涵蓋我的情況。 https://www.ardata.fr/en/post/2019/04/26/share-reactive-among-shiny-modules/

關於如何解決這個問題的任何想法？

這是我的代碼：

library(shiny)
library(shinydashboard)

readUI <- function(id, label = "Read") {

  ns <- NS(id)

  tagList(
    valueBoxOutput(ns("showX"))
  )
}

read <- function(input, output, session, x) {

  ns <- session$ns

  output$showX <- renderValueBox({
    valueBox(x(), "x")
  })

}

writeUI <- function(id, label = "Write") {

  ns <- NS(id)

  tagList(
    selectizeInput(ns("selectX"), "Select a value for x", choices = 1:10),
    actionButton(ns("submit"), "Submit")
  )
}

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

  ns <- session$ns

  toReturn <- reactiveValues(x = data.frame(a=c(1), b=c(2), c=c(3)), trigger = NULL)

  observeEvent(input$submit, {
    toReturn$x$a <- as.numeric(input$selectX)
    toReturn$trigger <- toReturn$trigger + 1
  })

  return(toReturn)

}

readAndWriteUI <- function(id, label = "ReadAndWrite") {

  ns <- NS(id)

  tagList(
    valueBoxOutput(ns("showX")),
    selectizeInput(ns("selectX"), "Select a value for x", choices = 1:10),
    actionButton(ns("submit"), "Submit")
  )

}

readAndWrite <- function(input, output, session, x) {

  ns <- session$ns

  toReturn <- reactiveValues(x = x, trigger = NULL)

  output$showX <- renderValueBox({
    valueBox(x(), "x")
  })

  observeEvent(input$submit, {
    toReturn$x$a <- as.numeric(input$selectX)
    toReturn$trigger <- toReturn$trigger + 1
  })

  return(toReturn)

}

ui <- dashboardPage(

  dashboardHeader(title = "Example"),

  dashboardSidebar(),

  dashboardBody(
    tabsetPanel(id = "mainTabSetPanel",
      tabPanel("Read", readUI("Read")),
      tabPanel("Write", writeUI("Write")),
      tabPanel("ReadAndWrite", readAndWriteUI("ReadAndWrite"))
    )
  )
)

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

  rv <- reactiveValues(x = data.frame(a=c(1), b=c(2), c=c(3)))

  callModule(read, "Read", reactive(rv$x))
  output_Write <- callModule(write, "Write")
  output_ReadAndWrite <- callModule(readAndWrite, "ReadAndWrite", reactive(rv$x))

  observeEvent(output_Write$trigger, {
    print("Updating x from Write")
    rv$x <- output_Write$x
    #updateTabsetPanel(session, "mainTabSetPanel", selected = "Read")
  })

  observeEvent(output_ReadAndWrite$trigger, {
    print("Updating x from ReadAndWrite")
    rv$x <- output_ReadAndWrite$x
    #updateTabsetPanel(session, "mainTabSetPanel", selected = "Read")
  })
}

shinyApp(ui, server)

Answer 1

請嘗試以下操作：

library(shiny)
library(shinydashboard)

readUI <- function(id, label = "Read") {

    ns <- NS(id)

    tagList(
        valueBoxOutput(ns("showX"))
    )
}

read <- function(input, output, session, x) {

    ns <- session$ns

    output$showX <- renderValueBox({
        valueBox(x(), "x")
    })

}

writeUI <- function(id, label = "Write") {

    ns <- NS(id)

    tagList(
        selectizeInput(ns("selectX"), "Select a value for x", choices = 1:10),
        actionButton(ns("submit"), "Submit")
    )
}

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

    ns <- session$ns

    toReturn <- reactiveValues(x = data.frame(a=c(1), b=c(2), c=c(3)), trigger = 0)

    observeEvent(input$submit, {
        toReturn$x$a <- as.numeric(input$selectX)
        toReturn$trigger <- toReturn$trigger + 1
    })

    return(toReturn)

}

readAndWriteUI <- function(id, label = "ReadAndWrite") {

    ns <- NS(id)

    tagList(
        valueBoxOutput(ns("showX")),
        selectizeInput(ns("selectX"), "Select a value for x", choices = 1:10),
        actionButton(ns("submit"), "Submit")
    )

}

readAndWrite <- function(input, output, session, x) {

    ns <- session$ns

    toReturn <- reactiveValues(x = x, trigger = 0)

    observeEvent(toReturn, {
        toReturn$x <- toReturn$x()
    }, once = TRUE)

    output$showX <- renderValueBox({
        valueBox(x(), "x")
    })

    observeEvent(input$submit, {
        toReturn$x$a <- as.numeric(input$selectX)
        toReturn$trigger <- toReturn$trigger + 1
    })

    return(toReturn)

}

ui <- dashboardPage(

    dashboardHeader(title = "Example"),

    dashboardSidebar(),

    dashboardBody(
        tabsetPanel(id = "mainTabSetPanel",
                    tabPanel("Read", readUI("Read")),
                    tabPanel("Write", writeUI("Write")),
                    tabPanel("ReadAndWrite", readAndWriteUI("ReadAndWrite"))
        )
    )
)

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

    rv <- reactiveValues(x = data.frame(a=c(1), b=c(2), c=c(3)))

    callModule(read, "Read", reactive(rv$x))
    output_Write <- callModule(write, "Write")
    output_ReadAndWrite <- callModule(readAndWrite, "ReadAndWrite", reactive(rv$x))

    observeEvent(output_Write$trigger, {
        print("Updating x from Write")
        rv$x <- output_Write$x
        #updateTabsetPanel(session, "mainTabSetPanel", selected = "Read")
    }, ignoreInit = TRUE)

    observeEvent(output_ReadAndWrite$trigger, {
        print("Updating x from ReadAndWrite")
        rv$x <- output_ReadAndWrite$x
        #updateTabsetPanel(session, "mainTabSetPanel", selected = "Read")
    }, ignoreInit = TRUE)
}

shinyApp(ui, server)

關鍵是在處理reactives和reactiveValues值時添加toReturn$x <- toReturn$x() ，但這只能運行一次，因此如下：

observeEvent(toReturn, {
    toReturn$x <- toReturn$x()
}, once = TRUE)

我發現的一個獨立問題是，即使對於write模塊，您的代碼也只能工作一次。 於是，我改變了trigger = NULL來trigger = 0 （因為你不能添加到NULL值），但隨后不得不在添加ignoreInit = TRUE為observeEvents在server忽略它們的啟動。

隨意測試這些，一一拿出我的補充來了解這個過程。 如果有什么需要澄清的，請在下面評論。