Question

我正在制作一个ShinyDashboard程序，在寻找在MenuItems中进行循环的方法时遇到了一些麻烦。具体来说，我正在寻找可以代替以下几行的内容：

menuItem(
  "Section1",
  tabName = "Section1",
  startExpanded = T,
  menuSubItem("Sub Menu 1", tabName = "tab1"),
  menuSubItem("Sub Menu 2", tabName = "tab2")
  ),

menuItem(
  "Section2",
  tabName = "Section2",
  startExpanded = T,
  menuSubItem("Sub Menu 1", tabName = "tab1"),
  menuSubItem("Sub Menu 2", tabName = "tab2")
  )

这是我尝试过的：

lapply(1:2, function(i){
       do.call(menuItem, c(text = paste0("Section",i), tabName =paste0("Section",i), startExpanded = T,
       lapply(1:2, function(j) {
           menuSubItem(text = paste0("sub menu ", j), tabName=paste0("tab",j))
       }
       )))
  })

它抛出以下错误：

错误：$运算符对于原子向量无效

我读了一篇与dashboardBody-> tabItems

类似的文章。

How to make a function in a for loop or lapply loop in a tabItem dashboard shiny

非常感谢您的帮助。

Answer 1

我不确定是否要找到它，但是下面的代码动态创建了这两个菜单项及其子项。

library(shiny)
library(shinydashboard)


ui <- dashboardPage(
  dashboardHeader(title = "My Page"),
  dashboardSidebar(sidebarMenuOutput("sidebar_menu")),
  dashboardBody(
    NULL
  ) 
)

server <- shinyServer(function(input, output, session) { 
  output$sidebar_menu <- renderMenu({
    sidebarMenu(id = "tab",

                menuItem("Section1", tabName="Section2", startExpanded = T,
                         lapply(1:2, function(i) {
                           menuSubItem(paste0("Sub Menu ",i), tabName = paste0("tab",i))
                         })
                ),
                menuItem("Section2", tabName="Section2", startExpanded = T,
                         lapply(1:2, function(i) {
                           menuSubItem(paste0("Sub Menu ",i), tabName = paste0("tab",i))
                         })
                )
    )


  })

})
runApp(list(ui= ui, server = server))

Answer 2

找到了解决方案

output$menu <- renderMenu(
    {
      sidebarMenu(id = "sbm",
                  lapply(1:10, function(i){
                    do.call(menuItem, c(text = paste0("Section",i), tabName = paste0("Section",i), startExpanded = T,
                                        lapply(1:2, function(j) {
                                          menuSubItem(text = paste0("sub menu ", j), tabName=paste0("tab",j))
                                        }
                                        )))
                  }
                    ))
      })

有没有一种方法可以使sidebarMenu-> menuItems动态？

2 个答案: