在 Shiny selectInput 中实现键值对答案

【问题标题】：Implementing key-value pairs in Shiny selectInput在 Shiny selectInput 中实现键值对
【发布时间】：2019-07-09 09:52:18
【问题描述】：

我有想要在 Shiny selectInput 下拉列表中使用的键值对数据。

我希望用户从玩家姓名列表中进行选择，但随后我想使用相应的playerID 来过滤其他数据集。

有没有办法做到这一点？我当前的代码如下所示：

selectInput("player","Select a player", Players$fullName),

我希望玩家下拉菜单能够根据“团队”下拉菜单做出反应。我的完整代码是：

library(shiny)
library(dplyr)

setwd("C:/Users/Michael/Documents/Baseball/Retrosheet/Shiny")
Teams <- read.csv("TeamID.csv")  # List of team names
Players <- read.csv("TeamBatter.csv") # TeamName, fullName, retroID
PlayerData <- read.csv("playerExpectedRBI.csv")  # Data keyed on PlayerID


todrop <- Players$retroID
names(todrop) <- Players$fullName

ui <- fluidPage(

  selectInput("team","Select a team:",Teams$teamID),
  selectInput("player", "Select a player", todrop),
  tableOutput("playerSummary")
)

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

 observe({
      PlayerList <- reactive({Players %>% filter(teamID == input$team) %>%  select(fullName,retroID)})
      updateSelectInput(session,"player", choices=PlayerList()$fullName)
      SelectedPlayerSum <- reactive({PlayerData %>% filter(resbatter == input$player)}) 
      output$playerSummary <- renderTable({SelectedPlayerSum()})
      })

    }

    shinyApp(ui = ui, server = server)

我收到错误：（功能（选择，名称）中的错误： “choices”中的所有子列表都必须命名。

【问题讨论】：

标签： r shiny

【解决方案1】：

您基本上需要创建命名列表并将其传递给下拉列表。它将返回playerID 而不是播放器fullname。

library(shiny)

Players <- data.frame(fullname = c('John Doe', 'James Smith', 'John Smith'), playerID = c(1:3))
# create named list and pass it to dropdown
todrop <- Players$playerID
names(todrop) <- Players$fullname

ui <- fluidPage(
    selectInput("player","Select a player", todrop),
    uiOutput("out")
)

server <- function(input, output) {

    output$out <- renderUI({
        print(paste0("Players ID is: ", input$player)) # here you select player ID from dropdown (not fullnames) and can use input$player for your queries
    })
}

shinyApp(ui = ui, server = server)

【讨论】：