r - R Shiny でユーザー入力を使用してデータ テーブル出力をフィルター処理する

Question

ユーザーが特定の入力を選択できるようにするアプリに取り組んでいます。この場合、アプリはさまざまなオプションから選択する 2 つの selectizeInput オプションを提供します。

以下はデータセットです。

data_test = data.frame(Name = c ("ABC","ABC","ABC","DEF","DEF", "XYZ", "XYZ", "PQR"),
          Country = c("US, Japan","US, Japan","US, Japan","Canada, US","Canada, US", "UK, US", "UK, US", "Germany"),
          Region = c("North America, Asia","North America, Asia","North America, Asia","North America","North America", "Europe, North America", "Europe, North America", "Europe"),
          Contact = c(1234,1234,1234,7578,7578,9898,9898,7660),
          ContactPerson = c("Geoff","Mary","Mike","Don","Sean","Jessica","Justin","John"))

ui.R で

dashboardPage(skin = "blue",
  dashboardHeader(title = 'My APP'),

  dashboardSidebar(
    sidebarMenu(
      menuItem("Profiles", tabName = "profiles", icon=icon("user")),
      menuItem("Search", tabName = "search", icon=icon("search")),
      menuItem("About App", tabName="about", icon = icon("info"))
    )
  ),
  dashboardBody(
    tabItems(
            tabItem(tabName ="profiles",
                    tabBox( title = "", 
                            width = 12, id = "tabset1", height = "850px",
                    tabPanel("People",
                            fluidRow(
                          box(title = "Filters", solidHeader = TRUE,
                              background = "blue" , collapsible = TRUE, width = 12,
                                  fluidRow(
                                    column(4,selectizeInput("country",label="Country",choices= NULL, multiple = TRUE)),
                                    column(4,selectizeInput("geogPref",label="Region",choices= NULL, multiple = TRUE))
                                          )
                              )
                            ),
                          box(title = "Filtered Results",
                              collapsible = TRUE, status = "success",
                              width = 12, DT::dataTableOutput('results'))
                            ),
                    tabPanel("Details",
                             fluidRow(
                                    box(width = 4, background = "blue",
                                        collapsible = TRUE, solidHeader = TRUE)
                                    )
                            )
                          )
                    ),
            tabItem(tabName ="search",
                    titlePanel("Search"),

                    fluidRow(
                            )  
                    ),
            tabItem(tabName="about",
                    titlePanel("About APP"),
                    HTML("This is an app.")
                    )
            )
      )
)

server.R で

library(shiny)
trim.leading <- function (x)  sub("^\\s+", "", x)

uniqueValues <- function(x){
values <- c()
s <- (unlist(strsplit(x, ",", fixed = TRUE)))
v <- trim.leading(s)
}    

geog <- c()
geog <- unique(unlist(c(geog, sapply(data_set$Region, uniqueValues))))


shinyServer(function(input, output, session) {

  updateSelectizeInput(session, 'country', choices = unique(data_set$Country), server = TRUE)
  updateSelectizeInput(session, 'geogPref', choices = geog, server = TRUE)

  country <-  reactive({
    c <- c()
    c <- c(c, input$country)
  })


  dataset <- reactive({
    data <- data_set
    if (input$country){
      data$c1 <- grepl(paste(country(), collapse = "|"), data$Country)
    }
    else {
      data$c1 <- TRUE
    }

    if (input$geogPref){
      data$c2 <- grepl(input$geogPref, data$Region)
    }
    else {
      data$c2 <- TRUE
    }


    data <- data[which(data$c1 == TRUE & data$c2 == TRUE ),c("Name", "Contact", "ContactPerson")]

    return (data)

  })

  output$results <- DT::renderDataTable(
    DT::datatable( unique(dataset()),
                   rownames = FALSE, options = list(searchable = FALSE)
    ) 

})

したがって、ユーザーの選択に基づいて、これらすべての文字列を含む行を除外し、関連する行のみでテーブルを更新する必要があります。フィルターを使用してテーブルを更新できません。私が得ているこのコードでは、このエラー:

Error in if: argument is of length zero
Stack trace (innermost first):
    96: <reactive:dataset> [D:\shinyapps\myapp/server.R#21]
    85: dataset
    84: unique
    83: DT::datatable
    82: exprFunc

誰かが私が間違っていることを手伝ってもらえますか?