Shiny R 确认删除后更新列表框

Question

这可能是关于shiny 的一个非常基本的问题 我有一个下拉列表，用户单击一个按钮，下拉菜单应更新为少一个项目

这是一个玩具示例

library(shiny)
library(shinythemes)

getData<- function()
{
  data <- c('A','B','C','D')
  return (data)
}   



ui <- fluidPage(

  selectInput("names", "Select Data", getData(), multiple = FALSE),
  actionButton("del","delete"),
  bsModal("modalnew", "Approve Data For Reporting", "del", size = "medium",
          HTML("Note: Confirm Deletion"),
          br(),br(),
          actionButton("delyes", "Yes"),
          actionButton("delno", "No")
  )

)

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

  # Reactive part that gets the data and populates the drop down
  my_sel = reactive({
    mydata = getData()
  })

  # Confirmation Menu to Approve the upload
  observeEvent(input$delyes, {
    toggleModal(session, "modalnew", toggle = "close")

# Delete an Item, Update the list box with one less item


  })

}

shinyApp(ui = ui, server = server)

一个项目应该从列表中消失。 我猜我基本上被困在反应位上。

在我与玩具示例分开的项目中，用户通过首先选择他们的区域来查看他们的数据，如果他们批准它，MySQL 中的存储过程会将数据移动到另一个表，并且列表框应该更新以删除列表框中的数据，因为它不再需要被批准

Answer 1

使用 reactiveValues 和 updateSelectInput 来改变 Select Input。

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

# Reactive part that gets the data and populates the drop down
v <- reactiveValues(
    mydata = getData()
)

# Confirmation Menu to Approve the upload
observeEvent(input$delyes, {
    toggleModal(session, "modalnew", toggle = "close")

    # Delete an Item, Update the list box with one less item
    v$mydata <- v$mydata[!v$mydata %in% input$names]

    #update the selection
    updateSelectInput(session, "names",
                      choices = v$mydata
    )

})   
}