r - Shiny 中的 conditionalPanel 导致 selectInput 失败

Question

我对为什么我的 selectInput 不起作用感到困惑。

包含 conditionalPanel 后，突然在 selectInput 中将名字从 John Doe 切换为 Joe Blow 不再有效——日期不更新， map 继续灰色。

我不明白为什么会这样。它起作用的唯一方法是如果我单击 no_date 然后返回并更改名称。然后事情就火了。但我无法弄清楚为什么/这是如何被打破的。

最初，一切都很好:

但是当我选择 Joe Blow 时:

注意日期没有改变。

conditionalPanel 发生了一些奇怪的事情，但对于我来说，我被困住了。感谢您阅读本文。

UI.R

library(shiny)
library(ggplot2)
library(dplyr)
library(leaflet)


DF <- data.frame(lon=c(-120.6596156, -87.27751, -119.7725868, -124.2026, -117.1858759),  
                 lat=c(35.2827524, 33.83122, 36.7468422, 41.75575, 34.5008311), 
                 date=c('2014-03-14', '2014-01-11', '2013-11-22', '2012-08-23', '2013-08-23'),
                 city=c('San Luis Obispo', 'Jasper', 'Fresno', 'Crescent City', 'Apple Valley'), 
                 P1_name=c('John Doe', 'John Doe', 'John Doe', 'John Doe', 'Joe Blow'))

DF[, c('date', 'city', 'P1_name')] <- sapply(DF[, c('date', 'city', 'P1_name')], as.character)


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

  output$fdate<-renderUI({
    selectInput('dates', 'Select date', choices=DF[which(DF$P1_name == input$person), ]$date, selectize = FALSE)
  })

  output$map<-renderLeaflet({
    DF <- filter(DF, P1_name==input$person, date==input$dates)    
    output$city <-renderText({c("Location:", DF$city)})


    m <- leaflet() %>%
      addTiles() %>%  # Add default OpenStreetMap map tiles
      setView(lng=DF$lon, lat=DF$lat, zoom=5) %>%
      addMarkers(lng=DF$lon, lat=DF$lat, popup=DF$city)

  })

}

ui <- fluidPage(
  titlePanel("Testing Shiny"),
  sidebarLayout (
    sidebarPanel(

      selectInput('person', 'Select person', choices=unique(DF$P1_name), selectize = FALSE),

      radioButtons('radio', 'Select method', choices=c('show_date', 'no_date'), selected = NULL, inline = TRUE),
      conditionalPanel(
        condition = "input.radio == 'show_date'",
        uiOutput('fdate')

      ),

      textOutput("city")

    ),

    mainPanel(
      leafletOutput('map')
    )  
  ))

shinyApp(ui = ui, server = server)

Answer 1

本质上output$fdate应该和'dates'同名

library(shiny)
library(ggplot2)
library(dplyr)
library(leaflet)


DF <- data.frame(lon=c(-120.6596156, -87.27751, -119.7725868, -124.2026, -117.1858759),  
                 lat=c(35.2827524, 33.83122, 36.7468422, 41.75575, 34.5008311), 
                 date=c('2014-03-14', '2014-01-11', '2013-11-22', '2012-08-23', '2013-08-23'),
                 city=c('San Luis Obispo', 'Jasper', 'Fresno', 'Crescent City', 'Apple Valley'), 
                 P1_name=c('John Doe', 'John Doe', 'John Doe', 'John Doe', 'Joe Blow'))

DF[, c('date', 'city', 'P1_name')] <- sapply(DF[, c('date', 'city', 'P1_name')], as.character)


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

  output$dates<-renderUI({
    selectInput('dates', 'Select date', choices=DF[which(DF$P1_name == input$person), ]$date, selectize = FALSE)
  })

  output$map<-renderLeaflet({
    validate(
      need(!is.null(input$dates),""),
      need(!is.null(input$person),"")
    )
    DF <- filter(DF, P1_name==input$person, date==input$dates)    
    output$city <-renderText({c("Location:", DF$city)})


    m <- leaflet() %>%
      addTiles() %>%  # Add default OpenStreetMap map tiles
      setView(lng=DF$lon, lat=DF$lat, zoom=5) %>%
      addMarkers(lng=DF$lon, lat=DF$lat, popup=DF$city)

  })

}

ui <- fluidPage(
  titlePanel("Testing Shiny"),
  sidebarLayout (
    sidebarPanel(

      selectInput('person', 'Select person', choices=unique(DF$P1_name), selectize = FALSE),

      radioButtons('radio', 'Select method', choices=c('show_date', 'no_date'), selected = NULL, inline = TRUE),
      conditionalPanel(
        condition = "input.radio == 'show_date'",
        uiOutput('dates')

      ),

      textOutput("city")

    ),

    mainPanel(
      leafletOutput('map')
    )  
  ))

shinyApp(ui = ui, server = server)