条件面板闪亮应用程序中的复选框不显示

Question

我正在尝试使用多张表格从Excel构建应用程序。它工作正常但复选框不显示，即使它实际上影响输出。我知道它会影响输出，因为当我消除了checkboxGroupInput的选定选项时，不显示任何行，否则它是预期的。也许有人可以告诉我为什么复选框没有按预期显示在侧边栏上。提前谢谢。

 require('shiny')
 library(readxl)
 read_excel_allsheets <- function(filename) {
  sheets <- readxl::excel_sheets(filename)
 x <-   lapply(sheets, function(X) readxl::read_excel(filename, sheet = X,  
  range =  cell_rows(c(6, NA))))
 names(x) <- sheets
  x
  }
 data <- read_excel_allsheets("data path")
 ui <- fluidPage(
  title = "Examples of DataTables",
  sidebarLayout(
    sidebarPanel(
      conditionalPanel(
       'input.dataset === "CUB 9"',
        checkboxGroupInput("show_vars", "Companies:",
                        unique(data$'CUB 9'$Company), 
                        selected = unique(data$'CUB 9'$Company))
   ),
   conditionalPanel(
    'input.dataset === "CUP 14"',
     checkboxGroupInput("show_vars1", "Companies: in CUP 14",
                      unique(data$'CUP  14'$Company), 
                      selected = unique(data$'CUP  14'$Company))
  )
 ),
 mainPanel(
  tabsetPanel(
    id = 'dataset',
    tabPanel("data$'CUB 9'", dataTableOutput("mytable1")),
    tabPanel("data$'CUP  14'", dataTableOutput("mytable2"))
    )
   )
  )
 )

server <- 
        function(input, output) {
          output$mytable1 <- renderDataTable({data$'CUB 9'[which(data$'CUB 
          9'$Company %in% c(input$show_vars)),]
           })
        output$mytable2 <- renderDataTable({data$'CUP  14'[which(data$'CUP  
         14'$Company %in% c(input$show_vars1)),] 
          })
  }
 shinyApp(ui, server)