2

我的闪亮算法（底部的 app.R 代码）：

  • 要求用户上传文件
  • 提供带有选项“无”、“国家”、“州”、“城市”的下拉字段
  • 选择“无”时，只应出现文本输出
  • 选择“国家/地区”时，应仅显示国家/地区过滤器
  • 选择“州”时，应出现国家和州过滤器
  • when "City" is selected, both country and city filters should appear and any existing state filter from previous selections should disappear

我在代码中所做的：对“无”和“国家”使用 IF 条件；用于“州”和“城市”的开关。

我的问题： 一切都按预期工作，除了一个：如果我们在选择“None”后选择“State”，我会看到 textOutput 和 State filter 而不是 country 和 state filters。发生这种情况是因为“无”或“国家/地区”中的 IF 语句与 switch() 不同，它只打印 UI，如果进行了另一个选择，则不会清除 UI

我的约束：

  • 国家/地区过滤器输入需要在代码中重复（“州”应该同时提供国家和州过滤器，“城市”类似）但我们不能在闪亮代码中复制具有相同 ID 的输入

  • 我不能使用不同的国家过滤器 ID 来提供相同的输入，因为我需要在多个地方读取国家过滤器中的输入值，并且我需要复制所有这些，这会使一切复杂化

我需要帮助的地方： 我唯一的问题是，如果用户在“无”（绕过“国家”！！！）。

真的需要这个东西来解决。任何帮助，将不胜感激

谢谢！

虚拟数据：https ://docs.google.com/spreadsheets/d/1E9dbtOMm1-7ZjIHu3Ra_NyFBHrCQdITG2_xuMIMKDOs/edit?usp=sharing

应用程序.R代码

library(shiny)

ui <- fluidPage(

  fileInput("file_attr", "Door attributes:"),
  selectInput("select", label = "Region Drop down", choices = list("None", "Country", "State","City"), selected = "None"),
  uiOutput("NoneCountryFilter"),
  uiOutput("StateCityFilter")
)

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

  #Reading input
  data_attr <- reactive({
    file1 <- input$file_attr
    if(is.null(file1)){return()} 
    read.table(file=file1$datapath, sep=",", header = TRUE, stringsAsFactors = FALSE)
  })

  #Filter interactivity

  #Reading Lists
  countries <- reactive({
    if(is.null(data_attr()$Country)){return()}
    data_attr()$Country
  })

  states <- reactive({
    if(is.null(data_attr()$State)){return()}
    data_attr()$State[data_attr()$Country %in% input$show_vars]
  })

  cities <- reactive({
    if(is.null(data_attr()$City)){return()}
    data_attr()$City[data_attr()$Country %in% input$show_vars]
  })


  #Filters based on Region Drop down

  observeEvent(input$file_attr,{ 
    observe({

      if ("None" %in% input$select){
        output$NoneCountryFilter <- renderUI({
          if(is.null(data_attr()$Country)){return()}
          h4("No region Selected")              
        })        
      }

      if ("Country" %in% input$select){
        output$NoneCountryFilter <- renderUI({
          if(is.null(data_attr()$Country)){return()}
          selectizeInput('show_vars', 'Country Filter', choices = c("Select All","None", unique(countries())), multiple = TRUE)
        })    
      }        
    })

    output$StateCityFilter <- renderUI({

      switch(input$select,                
             "State" = (
               selectizeInput('show_vars_state', 'State Filter', choices = c("Select All","None", unique(states())), multiple = TRUE)
             ),
             "City" = (
               selectizeInput('show_vars_city', 'City Filter', choices = c("Select All","None", unique(cities())), multiple = TRUE)
             )         
      )         
    })       
  })

  #Giving "Select ALL" and "None" Functionality to each filter (This part is redundant for the current problem. I am keeping this so that I could check any solution from stackoverflow should not effect other functionalities)

  #Countries- SelectAll & None
  observe({
    if ("Select All" %in% input$show_vars){
      selected_choices <- setdiff(c("Select All",unique(countries())), "Select All")
      updateSelectizeInput(session, 'show_vars', choices = c("Select All","None",unique(countries())), selected = selected_choices) 
    }
  })  


  observe({
    if ("None" %in% input$show_vars){
      updateSelectizeInput(session, 'show_vars', choices = c("Select All", "None", unique(countries())),selected = "")
    }
  })


  #State- SelectAll & None

  observe({
    if ("Select All" %in% input$show_vars_state){
      selected_choices <- setdiff(c("Select All",unique(states())), "Select All")

      updateSelectizeInput(session, 'show_vars_state', choices = c("Select All","None",unique(states())), selected = selected_choices)

    }
  })

  observe({
    if ("None" %in% input$show_vars_state){
      updateSelectizeInput(session, 'show_vars_state', choices = c("Select All", "None", unique(states())),selected = "")
    }
  })        

  #City- SelectAll & None

  observe({

    if ("Select All" %in% input$show_vars_city){

      selected_choices <- setdiff(c("Select All",unique(cities())), "Select All")

      updateSelectizeInput(session, 'show_vars_city', choices = c("Select All", "None", unique(cities())), selected = selected_choices)

    }
  })

  observe({

    if ("None" %in% input$show_vars_city){
      updateSelectizeInput(session, 'show_vars_city', choices = c("Select All", "None", unique(cities())),selected = "")
    }
  })    
}

shinyApp(ui = ui, server = server)
4

1 回答 1

0

您可以使用conditionalPanel它来确定根据特定条件显示哪些元素。

笔记：

  • 我用req()在，data_attr因为这是检查file_attr. 您不必使用is.null().

  • 我conditionalPanel为国家、州、城市使用了三个，并为每个指定了条件。

  • 在条件里面，input.select使用的是 not input$select。

library(shiny)

ui <- fluidPage(

  fileInput("file_attr", "Door attributes:"),
  selectInput("select", label = "Region Drop down",
              choices = list("None", "Country", "State","City"), selected = "None"),

  # Selectize Inputs ---------------
  uiOutput("Country_List"),
  uiOutput("State_List"),
  uiOutput("City_List")
)

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

  #Reading input
  data_attr <- reactive({
    req(input$file_attr) # make sure a file was uploaded

    read.table(file=input$file_attr$datapath, sep=",", header = TRUE, stringsAsFactors = FALSE)
  })

  # Country selectizeInput ----------------------
  output$Country_List <- renderUI({
    conditionalPanel(
      condition = "input.select == 'Country' | input.select == 'State'| input.select == 'City' ",
      selectizeInput('show_var', 'Country Filter',
                     choices = c("Select All","None", unique(data_attr()$Country)), multiple = TRUE)
    )
  })

  # State selectizeInput ----------------------
  output$State_List <- renderUI({
    conditionalPanel(
      condition = "input.select == 'State' ",
      selectizeInput('show_vars_state', 'State Filter',
                     choices = c("Select All","None", unique(data_attr()$State)), multiple = TRUE)
    )
  })

  # City selectizeInput -----------------------
  output$City_List <- renderUI({
    conditionalPanel(
      condition = "input.select == 'City' ",
      selectizeInput('show_vars_city', 'City Filter',
                     choices = c("Select All","None", unique(data_attr()$City)), multiple = TRUE)
    )
  })

}

shinyApp(ui = ui, server = server)
于 2017-03-21T12:54:09.980 回答