R 通过shiny 的刷子 Select 数据

我有一个可复制的shiny ，我曾try 为情节实现brushedPoints，然而，我只是得到了错误.有没有办法解决这个问题，这样当我用画笔在绘图上单击或 Select 一个点时，连接到它的数据就会显示在表格中？

错误:brushedPoints: 'xvar' ('x') not in names of input

library(shiny)
library(plotly)

dataset <- mtcars

ui <- shinyUI(pageWithSidebar(
  headerPanel("Mtcars"),
  sidebarPanel(sliderInput('sampleSize', 'Sample Size', min=10, max=nrow(dataset),
                           value=min(10, nrow(dataset)), step=5, round=0),
               selectInput('x', 'X', names(dataset)),
               selectInput('y', 'Y', names(dataset), names(dataset)[[2]]),
               selectInput('color', 'Color', c('None', names(dataset))),
               checkboxInput('smooth', 'Smooth'),
               selectInput('facet_row', 'Facet Row', c(None='.', names(dataset))),
               selectInput('facet_col', 'Facet Column', c(None='.', names(dataset))),
               hr(),
               checkboxInput("plotly1", "Interactive plot!",value = FALSE, width=140),
               actionButton("plot", "Plot!")
  ),
  mainPanel(
    plotOutput('plot', click = "plot_click",
               hover = hoverOpts(id = "plot_hover", delayType = "throttle"),
               brush = brushOpts(id = "plot_brush")),
    tableOutput("plot_brushedpoints")

  )
))

server<- shinyServer(function(input, output) { 
  dataset <- reactive( { mtcars[sample(nrow(mtcars), input$sampleSize),] }) 
  gragh <- reactive({
    p <- ggplot(dataset(), aes_string(x=input$x, y=input$y)) + geom_point()
    if (input$color != 'None')
      p <- p + aes_string(color=input$color)
    facets <- paste(input$facet_row, '~', input$facet_col)
    if (facets != '. ~ .')
      p <- p + facet_grid(facets)
    
    if (input$smooth)
      p <- p + geom_smooth()
    
    p
  }) |> bindEvent(input$plot)
  
  output$plot <- renderPlot({
    gragh()
  })
  
  output$plot_brushedpoints <- renderTable({
    df<- mtcars  
    res <- brushedPoints(df, input$plot_brush, "x", "y",allRows = TRUE)
    if (nrow(res) == 0|is.null(res))
      return(NULL)
    res
  })
  
  
  
  
})