r - ShinyDashboard 动态要点

Question

我希望有一个简单的问题，可以将标签有序列表传递到 Shiny 的仪表板中。我想做的是有一个函数，可以根据过滤的类别生成项目符号的有序列表。

这是一个简单的示例，展示了我希望能够使用名为 nba_teams 的数据框执行的操作

teams    conference
Bulls    Eastern
Nuggets  Western
Celtics  Eastern
Lakers   Western

现在，如果我编写此函数，它将列出各个 session 的列表:

for (row in 1:nrow(nba_teams)){
  teams <- nba_teams[row, "teams"]
  conference <- nba_teams[row,"conference"]

  if(grepl("Western",conference)){
   print(tags$li(teams))
 }
}

掘金

湖人队

我想做的是将其放在选项卡框中，以便:

box(
 title = "Western Conference",
 tags$ol(
  for (row in 1:nrow(nba_teams)){
  teams <- nba_teams[row, "teams"]
  conference <- nba_teams[row,"conference"]

  if(grepl("Western",conference)){
   print(tags$li(teams))
 }
})),

但这只是将框留空，并且不会为每个观察结果填充项目符号点。

有什么建议吗？谢谢!

Answer 1

在这种情况下我会使用lapply:

library(shiny)  
library(shinydashboard)

nba_teams <- data.frame(team = c("Bulls", "Nuggest", "Celtics", "Lakers"),
                        conference = c("Eastern", "Western", "Eastern", "Western"))

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(),
  dashboardBody(
    box(
      title = "Western Conference",
      tags$ol(
        lapply(1:nrow(nba_teams), function(x) {
          if (nba_teams$conference[x]=="Western") {
            return(tags$li(nba_teams$team[x]))
          }
        })
      )
    )
  )
)

server <- function(input, output, session) {}

shinyApp(ui, server)