Question

我想制作一个Shiny应用程序，用户可以在其中上传自己的rda / rds文件或使用默认数据集。输入选择选项将根据他们要使用其向下数据还是默认数据而变化。

例如在我的代码中，我希望mtbSelection的选择根据conditionalPanel上的值进行更改。

我在理解如何在服务器功能中加载.rda / .rds文件时遇到了麻烦，而且我不确定为什么updateSelectInput无法正常工作。任何帮助将不胜感激！

library(shiny)
library(shinythemes)

ui <- fluidPage(
  theme = shinytheme("paper"),
  checkboxInput("default_data", "Would you like to use default datasets?", value = TRUE),

  conditionalPanel(condition = "input.default_data == true",
                   selectizeInput(inputId = "mtb2", label = "Please choose a metabolomic dataset",
                                  choices = "mtb2",
                                  options = list(placeholder = 'Select a default metabolomic file below',onInitialize = I('function() { this.setValue(""); }'))
                   ),
                   selectizeInput(inputId = "geneExp2", label = "Please choose a transcriptome dataset",
                                  choices = "geneExp2",
                                  options = list(placeholder = 'Select a default transcriptome file below',onInitialize = I('function() { this.setValue(""); }'))
                   )
  ),
  conditionalPanel(condition = "input.default_data == false",
                   fileInput(inputId = "file_mtb", label = "Please upload a metabolomic dataset",
                             multiple = FALSE, accept = c('.RData', '.rda', '.rds'), placeholder = "  No file selected"
                   ),
                   fileInput(inputId = "file_ge", label = "Please upload a transcriptome dataset",
                             multiple = FALSE, accept = c('.RData', '.rda', '.rds'), placeholder = "  No file selected"
                   )


  ),

  selectInput("mtbSelection", strong("Select a metabolite of interest"), choices = "",
              multiple = FALSE)

)

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

  UploadMtbData <- reactive({
    infile <- input$file_mtb
    if (is.null(infile)){
      return()
    } else {
      return(readRDS(infile$datapath))
    }
  })

  observe({
    if (is.null(input$file_mtb)) #makes sure that the uploaded file is not null
      return()

    obj<-switch(input$file_mtb,
                 mtb2,
                 infile)

    var.opts <- colnames(obj)

    updateSelectInput(session, "mtbSelction", choices = var.opts)
  })



}

shinyApp(ui = ui, server = server)

Answer 1

更新：我更新了if语句。非常重要的是，由于输入错误，updateSelectInput无法正常工作！这是生成我使用的伪数据的代码：

data(cars)
saveRDS(cars,'cars.rds')

我建议使用以下服务器代码（其余代码可以保持不变）：

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

# reactive data
  mtbData <- reactive({
    # read default or user data
    if(input$default_data == TRUE || is.null(input$file_mtb)){
      # load your data here
    } else {
      # get input
      infile <- input$file_mtb
      # read and return
      readRDS(infile$datapath) 
    }
  })

  # update observer
  observe({
    # update
    updateSelectInput(session, "mtbSelection", choices = colnames(mtbData()))
  })

}

基于上传文件的变量或R Shiny中的默认数据集的数据分析

1 个答案: