在 tabItem() 中動態創建 box()

Question

我正在使用shinydashboard構建一個shiny應用程序。 其目的是在每個tabItem() （即儀表板的每個頁面）內顯示一組“卡片”（技術上是box()元素）。 該應用程序由 external.csv 文件（在此表示中為 object dat ）驅動，該文件 (1) 定義應用程序內的頁面，(2) 指定每個頁面內box()元素的數量。

我已經能夠使用dat中的類別成功創建一組tabItem （即頁面）。 從這里開始，我無法弄清楚如何為每個tabItem動態添加正確數量的框。 如果您檢查dat ，您將看到有兩個類別（頁面）：藍色和綠色。 藍色類別需要我渲染兩個框（框 A 和框 B），而綠色類別需要我渲染框 C - E。因此，名為“藍色”的頁面應該呈現兩個框，而名為“綠色”的頁面應該渲染三個盒子。

有人可以幫助我使用以下代碼，以便為正確的頁面呈現正確的框嗎？ 如果 box_name 和 box_desc 可以分別作為box()的標題和內容出現，則更加感謝！

library(shiny)
library(shinydashboard)

dat<-tibble::tibble(category = c("blue", "blue", "green", "green", "green"), 
                    box_name = c("Box A", "Box B", "Box C", "Box D", "Box E"),
                    box_desc = c("Foo", "Bar", "Bar", "Foo", "Foo"))

sidebar <- dashboardSidebar(
  sidebarMenu(
    menuItem("Blue", tabName = "blue", icon = icon("dashboard")),
    menuItem("Green", icon = icon("th"), tabName = "green")
  )
)

body <- dashboardBody(
  uiOutput("render_reports")
)
header<-dashboardHeader()

ui <- dashboardPage(header, sidebar, body)

server <- function(input, output) {
  
  output$render_reports <- renderUI({
    
    pages <- lapply(unique(dat$category), function(name){
      
      tabItem(tabName = name, fluidRow(box(
        title = name, paste0("Something here about ", name), width = 12, solidHeader = TRUE, status = "primary"
      )),

      fluidRow(
        
        box(title = "box_title here", "box_desc here")
        
      ))
    })
    
    items <- c(pages)
    do.call(tabItems, items)
    
  })
  
}


shinyApp(ui, server)

Answer 1

需要renderUI嗎？

沒有renderUI它可以正常工作（並且速度更快）：

library(shiny)
library(shinydashboard)

dat <- tibble::tibble(
  category = c("blue", "blue", "green", "green", "green"),
  box_name = c("Box A", "Box B", "Box C", "Box D", "Box E"),
  box_desc = c("Foo", "Bar", "Bar", "Foo", "Foo")
)

sidebar <- dashboardSidebar(sidebarMenu(
  menuItem("Blue", tabName = "blue", icon = icon("dashboard")),
  menuItem("Green", tabName = "green", icon = icon("th"))
))

body <- dashboardBody({
  items <- lapply(unique(dat$category), function(name) {
    tabItem(tabName = name, fluidRow(
      lapply(which(dat$category %in% name), function(i) {
        box(
          dat$box_desc[i],
          title = dat$box_name[i],
          paste0("Something here about ", name),
          width = 12,
          solidHeader = TRUE,
          status = "primary"
        )
      }))
    )})
  do.call(tabItems, items)
})

header <- dashboardHeader()

ui <- dashboardPage(header, sidebar, body)

server <- function(input, output) {}

shinyApp(ui, server)

使用renderUI僅在切換選項卡后才會呈現項目 - 因為在首次呈現 dashboardBody 時框不存在：

library(shiny)
library(shinydashboard)

dat <- tibble::tibble(
  category = c("blue", "blue", "green", "green", "green"),
  box_name = c("Box A", "Box B", "Box C", "Box D", "Box E"),
  box_desc = c("Foo", "Bar", "Bar", "Foo", "Foo")
)

sidebar <- dashboardSidebar(sidebarMenu(
  menuItem("Blue", tabName = "blue", icon = icon("dashboard")),
  menuItem("Green", tabName = "green", icon = icon("th"))
))

body <- dashboardBody(uiOutput("renderReports"))
header <- dashboardHeader()

ui <- dashboardPage(header, sidebar, body)

server <- function(input, output) {
  output$renderReports <- renderUI({
    items <- lapply(unique(dat$category), function(name) {
      tabItem(tabName = name, fluidRow(
        lapply(which(dat$category %in% name), function(i) {
        box(
          dat$box_desc[i],
          title = dat$box_name[i],
          paste0("Something here about ", name),
          width = 12,
          solidHeader = TRUE,
          status = "primary"
        )
      }))
    )})
    do.call(tabItems, items)
  })
}

shinyApp(ui, server)