R Shiny的updateDateInput中没有“datesdisabled”？

Question

我在 R Shiny 中构建了一个应用程序，它使用排除许多日期的时间序列数据。在应用程序中，用户可以选择一个新数据集，因此可用日期会发生变化。我正在使用updateDateInput 来更新dateInput 选择器。但是，updateDateInput 似乎不允许datesdisabled 功能？

这是一个代表：

library(shiny)

# Sample 3 dates and disable the rest
 
my_dates <- sample(seq(as.Date('2021-01-01'), as.Date('2021-01-31'), by = "day"), 3)    
date_choices <- seq.Date(from = min(my_dates), to = max(my_dates), by = 1)
dates_disabled <- date_choices[!(date_choices %in% my_dates)]

ui <- fluidPage(
    dateInput("date", "Select Date",
              min = min(date_choices),
              max = max(date_choices),
              value = max(date_choices),
              datesdisabled = dates_disabled),
    actionButton("click", "Click Me")
)

server <- function(input, output, session) {
    observeEvent(input$click, {
        my_dates <- sample(seq(as.Date('2021-01-01'), as.Date('2021-01-31'), by = "day"), 3)
        date_choices <- seq.Date(from = min(my_dates), to = max(my_dates), by = 1)
        dates_disabled <- date_choices[!(date_choices %in% my_dates)]
        updateDateInput(
            session, 
            "date",
            min = min(date_choices),
            max = max(date_choices),
            value = max(date_choices),
            datesdisabled = dates_disabled)
    })
}

shinyApp(ui, server)

单击按钮并运行updateDateInput 时，我收到此错误：

警告：updateDateInput 中的错误：未使用的参数（datesdisabled = 日期禁用）

我猜可以选择将日期更改为字符并使用selectInput？但是我没有得到漂亮的日历！

Answer 1

你是对的，datesdisabled 参数在更新函数中不可用。您可以通过将 UI 声明移至服务器并使用 renderUI() 将其提供给客户端来更改禁用日期。

该示例未在 UI 中声明日期输入，而是声明了 uiOutput("date")。服务器可以使用datesdisabled 参数动态创建dateInput。这样您就可以更改禁用日期。

该示例将在每次单击按钮后仅选择 3 个启用日期。

# Reprex: The actual implementation of this uses data from a file:
#    1. Reads data file before ui and server are established
#    2. Does a bunch of calculations
#    3. Identifies dates that exist in data file
#    4. The data file is getting updated in the background from another application.
#    5. Allows user to click the button to update the data file. Reprex shows code
#       that is used to update the date selector based on new data read. Dates are 
#       random in reprex, but would come from data file in actual code.

# Sample 3 dates and disable the rest - actual code reads data file here
#   and parses out dates that exist in records

my_dates <- seq(as.Date('2021-01-01'), as.Date('2021-01-31'), by = "day")
date_choices <- sample(my_dates, 31-3)

ui <- fluidPage(
    uiOutput("date"), textOutput("disabled"),
    actionButton("click", "Click Me")
)

server <- function(input, output, session) {
    dates_disabled <- reactiveVal(NULL)
    
    # Init 'dates_disabled()' once before Shiny flushes the reactive system with callback,
    #   using date_choices that exist in original data set

    onFlush(fun = function () {dates_disabled(date_choices)}, once = TRUE)
    
    # dateInput widget
    output$date <- renderUI({
        maxDate <- as.Date(max(setdiff(my_dates, dates_disabled())),
                           origin = "1970-01-01")
        dateInput(input = "date", 
                  label = "Select Date",
                  min = min(my_dates),
                  max = max(my_dates),
                  value = maxDate,
                  datesdisabled = dates_disabled())
    })
    
    # This output makes it easier to test if it works by showing the enabled dates
    output$disabled <- renderPrint({
        req(dates_disabled()) # only run this when 'dates_disabled' is initialized properly
        Enabled <- as.Date(setdiff(seq(as.Date('2021-01-01'), as.Date('2021-01-31'), by = "day"), 
                                   dates_disabled()), 
                           origin = '1970-01-01')
        paste("Enabled:", paste(Enabled[order(Enabled)], collapse = ", "))
    })
    
    # Set new datesdisabled on button click
    #    Actual code would read updated data file and parse new dates
    observeEvent(input$click, {
        SelectedDates <- sample(my_dates, 31-3)
        dates_disabled( SelectedDates )
    })
}

shinyApp(ui, server)