如何在R Shiny中动态链接2个小部件选项？

library(shiny)

ui <- fluidPage(
  selectInput("dropdown", "选择一个选项：", choices = c("选项1", "选项2", "选项3")),
  checkboxGroupInput("checkbox", "选择多个选项：", choices = NULL)
)

server <- function(input, output, session) {
  observeEvent(input$dropdown, {
    selected_option <- input$dropdown
    # 根据下拉菜单的值更新复选框的选项
    if (selected_option == "选项1") {
      choices <- c("选项1-1", "选项1-2", "选项1-3")
    } else if (selected_option == "选项2") {
      choices <- c("选项2-1", "选项2-2", "选项2-3")
    } else if (selected_option == "选项3") {
      choices <- c("选项3-1", "选项3-2", "选项3-3")
    }
    updateCheckboxGroupInput(session, "checkbox", choices = choices)
  })
}

shinyApp(ui, server)