Question

我正在尝试构建一个闪亮的应用程序，我可以在其中上传csv文件并根据列名称填充ui中左栏（滑动栏列）上的复选框。根据为y轴选择的列和为x轴选择的列，需要能够使用ggplot创建图表。

我的ui.R看起来像这样：

shinyUI(pageWithSidebar(
  headerPanel("CSV Viewer"),
  sidebarPanel(
    fileInput('file1', 'Choose CSV File',
              accept=c('text/csv', 'text/comma-separated-values,text/plain', '.csv')),
    tags$hr(),
    checkboxInput('header', 'Header', TRUE),
    radioButtons('sep', 'Separator',
                 c(Comma=',',
                   Semicolon=';',
                   Tab='\t'),
                 'Comma'),
    radioButtons('quote', 'Quote',
                 c(None='',
                   'Double Quote'='"',
                   'Single Quote'="'"),
                 'Double Quote'),

   checkboxGroupInput("variable", "Variable:", choices = names(data_set))
  ),
  mainPanel(
    tableOutput('contents')


  )
))

Server.R如下所示：

shinyServer(function(input, output) {
  output$contents <- renderTable({

    # input$file1 will be NULL initially. After the user selects and uploads a 
    # file, it will be a data frame with 'name', 'size', 'type', and 'datapath' 
    # columns. The 'datapath' column will contain the local filenames where the 
    # data can be found.

    inFile <- input$file1

    if (is.null(inFile))
      return(NULL)

    data_set<-read.csv(inFile$datapath, header=input$header, sep=input$sep, quote=input$quote)
  })

  output$choose_dataset <- renderUI({
    selectInput("dataset", "Data set", as.list(data_sets))
  })

  # Check boxes
  output$choose_columns <- renderUI({
    # If missing input, return to avoid error later in function
    if(is.null(input$dataset))
      return()

    # Get the data set with the appropriate name

    colnames <- names(contents)

    # Create the checkboxes and select them all by default
    checkboxGroupInput("columns", "Choose columns", 
                       choices  = colnames,
                       selected = colnames)
  })

})

我无法在滑块栏的数据集中加载列名？任何指针我怎么能这样做。我正在加载一个csv文件，一旦加载了文件，我需要能够加载使用我的数据集的列名填充滑块。

更新编辑：

添加了来自OP的请求（请参阅已接受答案中的注释）以读入csv并选择轴以使用ggplot进行绘图。另外还为此添加了答案。

Answer 1

这个答案只是解决了csv加载问题，请参阅下面的下一个答案，其中一个实际上是用ggplot进行绘图。

所以（在合并到一个文件中以便更容易处理之后），我向ui部分添加了checkboxGroupInput，并向服务器部分添加了相应的updateCheckboxGroupInput。我需要它来在数据集发生变化时更新组，因此我稍微重新构建了代码，使data_set加载部分reactive封装updateCheckboxGroupInput observer内的library(shiny) library(shinydashboard) library(leaflet) library(data.table) ui <- pageWithSidebar( headerPanel("CSV Viewer"), sidebarPanel( fileInput('file1', 'Choose CSV File', accept=c('text/csv', 'text/comma-separated-values,text/plain', '.csv')), tags$hr(), checkboxInput('header', 'Header', TRUE), checkboxGroupInput("inCheckboxGroup", "Checkbox group input:", c("label 1" = "option1", "label 2" = "option2")), radioButtons('sep', 'Separator', c(Comma=',', Semicolon=';', Tab='\t'), ','), radioButtons('quote', 'Quote', c(None='', 'Double Quote'='"', 'Single Quote'="'"), '"'), uiOutput("choose_columns") ), mainPanel( tableOutput('contents') ) ) server <- function(input, output,session) { dsnames <- c() data_set <- reactive({ req(input$file1) inFile <- input$file1 data_set<-read.csv(inFile$datapath, header=input$header, sep=input$sep, quote=input$quote) }) output$contents <- renderTable({ data_set() }) observe({ req(input$file1) dsnames <- names(data_set()) cb_options <- list() cb_options[ dsnames] <- dsnames updateCheckboxGroupInput(session, "inCheckboxGroup", label = "Check Box Group", choices = cb_options, selected = "") }) output$choose_dataset <- renderUI({ selectInput("dataset", "Data set", as.list(data_sets)) }) # Check boxes output$choose_columns <- renderUI({ # If missing input, return to avoid error later in function if(is.null(input$dataset)) return() # Get the data set with the appropriate name colnames <- names(contents) # Create the checkboxes and select them all by default checkboxGroupInput("columns", "Choose columns", choices = colnames, selected = colnames) }) } shinyApp(ui, server)。

所以这就是你想要的：

import config

以下是截图：

Answer 2

所以添加另一个答案以容纳一个额外的请求 - 它不仅读取文件，而且允许您选择用于绘图的列，它实际上在带有ggplot2的单独选项卡中绘制：

library(shiny)
library(shinydashboard)
library(leaflet)
library(data.table)
library(ggplot2)

ui <- pageWithSidebar(
  headerPanel("CSV Viewer"),
  sidebarPanel(
    fileInput('file1', 'Choose CSV File',
              accept=c('text/csv','text/comma-separated-values,text/plain','.csv')),
    tags$hr(),
    checkboxInput('header', 'Header', TRUE),
    fluidRow(
      column(6,radioButtons("xaxisGrp","X-Axis:", c("1"="1","2"="2"))),
      column(6,checkboxGroupInput("yaxisGrp","Y-axis:", c("1"="1","2"="2")))
    ),
    radioButtons('sep', 'Separator',
                 c(Comma=',', Semicolon=';',Tab='\t'), ','),
    radioButtons('quote', 'Quote',
                 c(None='','Double Quote'='"','Single Quote'="'"),'"'),
    uiOutput("choose_columns")
  ),
  mainPanel(
    tabsetPanel(
      tabPanel("Plot",plotOutput("plot")),
      tabPanel("Data", tableOutput('contents'))
    )
  )
)
server <- function(input, output,session) {
  dsnames <- c()

  data_set <- reactive({
    inFile <- input$file1

    if (is.null(inFile))
      return(mtcars)

    data_set<-read.csv(inFile$datapath, header=input$header, 
                       sep=input$sep, quote=input$quote)
  })

  output$contents <- renderTable({data_set()})

  observe({
    dsnames <- names(data_set())
    cb_options <- list()
    cb_options[ dsnames] <- dsnames
    updateRadioButtons(session, "xaxisGrp",
                             label = "X-Axis",
                             choices = cb_options,
                             selected = "")
    updateCheckboxGroupInput(session, "yaxisGrp",
                             label = "Y-Axis",
                             choices = cb_options,
                             selected = "")
  })
  output$choose_dataset <- renderUI({
    selectInput("dataset", "Data set", as.list(data_sets))
  })
  output$plot = renderPlot(
    {
      df <- data_set()
      gp <- NULL
      if (!is.null(df)){
        xv <- input$xaxisGrp
        yv <- input$yaxisGrp
        if (!is.null(xv) & !is.null(yv)){
          if (sum(xv %in% names(df))>0){ # supress error when changing files
            mdf <- melt(df,id.vars=xv,measure.vars=yv)
            gp <- ggplot(data=mdf) + 
               geom_point(aes_string(x=xv,y="value",color="variable"))
          }
        }
      }
      return(gp)
    }
  )
  output$choose_columns <- renderUI({

    if(is.null(input$dataset))
      return()
    colnames <- names(contents)
    checkboxGroupInput("columns", "Choose columns", 
                       choices  = colnames,
                       selected = colnames)
  }) 
}
shinyApp(ui, server)

产量：

根据csv文件的列名创建选择列表，以便在Shiny中进行绘图

更新编辑：

2 个答案: