闪亮的反应式输入添加和删除

Question

我正在尝试编写一个闪亮的应用程序，在其中生成一个列表并添加和删除一些元素。

我有一个模块可以将某些内容添加到我的列表中。

find_inputUI <- function(id){
  ns <- NS(id)
  tagList(
  sliderInput(ns("first"), "Choose a number:", min=0, max=100, 30),
  radioButtons(ns("second"), "Choose a colour:", choices=c("red", "green", "black")),
  actionButton(ns("press"), "Add to queue"))

}

find_input <- function(input, output, session){
  queue <- list()
 observeEvent(input$press, {
  queue_append <- list(input$first, input$second)
queue <<- append(queue, queue_append )})
 queue_ret <- eventReactive(input$press,{return(list(queue=queue, add=input$press))})

}

然后我调用它两次并连接两个不同的输入。 现在我想选择要删除的元素，但这不起作用。

source('/cloud/project/Queue/find_input.R')
library(shiny)

ui <- fluidPage(
  tagList(tabsetPanel(
    tabPanel("INPUT 1",
             find_inputUI("input1"),
             verbatimTextOutput("test")),
    tabPanel("INPUT 2",
             find_inputUI("input2")
    )
  ),
  actionButton("combine", "Show combined input"),
  verbatimTextOutput("combination"),
  uiOutput("del")
  )
)

# Define server logic required to draw a histogram
server <- function(input, output, session) {

  input_manual1 <- callModule(find_input,"input1")
  input_manual2 <- callModule(find_input, "input2")
  output$test <- renderPrint({input_manual1()$queue})

  appended <- eventReactive(input$combine, {
    return(append(input_manual1()$queue, input_manual2()$queue))
  })

  output$combination <- renderPrint({appended()})

  output$del <- renderUI({
    input$combine
    tagList(checkboxGroupInput("delete", "Choose do delete", seq(1:length(appended()))),
            actionButton("dodelete", "Delete selected"))
  })
  observeEvent(input$dodelete,{
    appended <<- appended()[-input$delete]
  })

}

# Run the application 
shinyApp(ui = ui, server = server)

也许有人可以告诉我到目前为止出了什么问题？

提前致谢！

Answer 1

下面是一个似乎可以工作的应用程序，但我不确定您的应用程序打算做什么。

一般来说，更喜欢使用非局部赋值<<-反应值（ reactiveVal ）。

appended <<- appended()[-input$delete]的代码appended <<- appended()[-input$delete]不正确。 它不会用原始值减去input$delete索引来替换appended()的输出。

library(shiny)

find_inputUI <- function(id){
  ns <- NS(id)
  tagList(
    sliderInput(ns("first"), "Choose a number:", min=0, max=100, 30),
    radioButtons(ns("second"), "Choose a colour:", choices=c("red", "green", "black")),
    actionButton(ns("press"), "Add to queue"))

}

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

  queue <- reactiveVal(list())

  observeEvent(input$press, {
    queue_append <- list(input$first, input$second)
    queue(append(queue(), queue_append))
  })

  queue_ret <- eventReactive(input$press, {
    list(queue=queue(), add=input$press)
  })

}

ui <- fluidPage(
  tagList(tabsetPanel(
    tabPanel("INPUT 1",
             find_inputUI("input1"),
             verbatimTextOutput("test")),
    tabPanel("INPUT 2",
             find_inputUI("input2")
    )
  ),
  actionButton("combine", "Show combined input"),
  verbatimTextOutput("combination"),
  uiOutput("del")
  )
)


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

  input_manual1 <- callModule(find_input,"input1")
  input_manual2 <- callModule(find_input, "input2")
  output$test <- renderPrint({input_manual1()$queue})

  appended <- reactiveVal(list())
  observeEvent(input$combine, {
    appended(append(input_manual1()$queue, input_manual2()$queue))
  })

  output$combination <- renderPrint({appended()})

  output$del <- renderUI({
    input$combine
    tagList(checkboxGroupInput("delete", "Choose do delete", seq_along(appended())),
            actionButton("dodelete", "Delete selected"))
  })

  observeEvent(input$dodelete,{
    appended(appended()[-as.integer(input$delete)])
  })

}

# Run the application 
shinyApp(ui = ui, server = server)