闪亮 - 使用insertUI的动态数据过滤器

Question

我是新手,并且正在尝试编写一个用户可以动态添加数据过滤器的应用程序(请参阅下面的代码).我认为insertUI和删除UI非常酷.但是,我有几个问题:

    1) I cannot address dynamically generates input$ids (see filterId in the code, l. 36 and l. 58)
    2) in updateCheckboxGroupInput (l. 62) checkboxes are not preselected.
    3) I cannot select data rows using which() (l. 74)
    4) The checkboxes are not displayed inside the column, but spread over the whole page.

我非常感谢任何提示.

谢谢,Jordi

这里的代码:

library(shiny)

rowvalues <- function(col,data) {
  as.list(unique(data[col]))
}

ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      fluidRow(
        column(6, actionButton('addFilter', 'Add filter')),
        column(6, actionButton('removeFilter', 'Remove filter')),
        offset = 6
      ),
      tags$hr(),
      tags$div(id = 'placeholderAddRemFilt'),
      tags$div(id = 'placeholderFilter'),
      width = 4 # sidebar
    ),
    mainPanel(
      tableOutput("data")
    )
  )
)

server <- function(input, output,session) {
  filter <- character(0)

  observeEvent(input$addFilter, {
    add <- input$addFilter
    filterId <- paste0('Filter', add)
    headers <- names(mtcars)
    insertUI(
      selector = '#placeholderFilter',
      ui = tags$div(
        # selectInput(filterId, label = paste0("Filter ",add), # does not work
        selectInput("ColFilter", label = paste0("Filter ",add), 
                    choices = as.list(headers), 
                    selected = 1),
        checkboxGroupInput("RowFilter", label = "Select variable values",
                           choices = NULL, selected = NULL, 
                           inline = TRUE, width = 4000),
        id = filterId
      )
    )

    filter <<- c(filter,filterId)
  })

  observeEvent(input$removeFilter, {
    removeUI(
      ## pass in appropriate div id
      selector = paste0('#', filter[length(filter)])
    )
    filter <<- filter[-length(filter)]
  })

  # observeEvent(input$filterId, { # does ntót work
  observeEvent(input$ColFilter, {
    col <- input$ColFilter
    values <- as.list(unique(mtcars[col]))[[1]]
    updateCheckboxGroupInput(session,"RowFilter", label = "Select variable    values", 
                              choices = values, selected = values, 
                              inline = TRUE)
  })

  output$data <- renderTable({
    col <- input$ColFilter
    rows <- input$RowFilter
    print(c("selected col: ",col))
    print(c("selected rows: ",as.vector(rows)))
    if(is.null(col)) mtcars
    else {
      mtcars[which(mtcars$col != rows),]
    }
  })
 }

shinyApp(ui = ui, server = server)

Answer 1

请参阅下面的代码以获取我的建议.我基本上做了你希望/尝试做的事情,即动态添加观察者,使每个新的过滤元素都有自己的观察者.事实证明:你可以做到.就像那样.所以我在精确的observeEvent中添加了观察者,其中ui元素被渲染,以给予他们所需的反应性.我甚至添加了"个人"删除按钮,这比仅移除最底部按钮更方便.此外,处理所有这些过滤器的逻辑将是一个聚合列表,它存储当前在各种过滤器中选择的所有信息.这使得renderTable部分更容易.

让自己熟悉代码,如果有任何不确定因素,请询问.

最好的祝福

library(shiny)

ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      fluidRow(
        column(6, actionButton('addFilter', 'Add filter')),
        offset = 6
      ),
      tags$hr(),
      tags$div(id = 'placeholderAddRemFilt'),
      tags$div(id = 'placeholderFilter'),
      width = 4 # sidebar
    ),
    mainPanel(
      tableOutput("data")
    )
  )
)

server <- function(input, output,session) {
  filter <- character(0)

  makeReactiveBinding("aggregFilterObserver")
  aggregFilterObserver <- list()

  observeEvent(input$addFilter, {
    add <- input$addFilter
    filterId <- paste0('Filter_', add)
    colfilterId <- paste0('Col_Filter_', add)
    rowfilterId <- paste0('Row_Filter_', add)
    removeFilterId <- paste0('Remove_Filter_', add)
    headers <- names(mtcars)
    insertUI(
      selector = '#placeholderFilter',
      ui = tags$div(id = filterId,
        actionButton(removeFilterId, label = "Remove filter", style = "float: right;"),
        selectInput(colfilterId, label = "Some Filter", choices = as.list(headers), selected = 1),
        checkboxGroupInput(rowfilterId, label = "Select variable values",
                           choices = NULL, selected = NULL, width = 4000)
      )
    )

    observeEvent(input[[colfilterId]], {

      col <- input[[colfilterId]]
      values <- as.list(unique(mtcars[col]))[[1]]

      updateCheckboxGroupInput(session, rowfilterId , label = "Select variable    values", 
                              choices = values, selected = values, inline = TRUE)

      aggregFilterObserver[[filterId]]$col <<- col
      aggregFilterObserver[[filterId]]$rows <<- NULL
    })

    observeEvent(input[[rowfilterId]], {

      rows <- input[[rowfilterId]]

      aggregFilterObserver[[filterId]]$rows <<- rows

    })

    observeEvent(input[[removeFilterId]], {
      removeUI(selector = paste0('#', filterId))

      aggregFilterObserver[[filterId]] <<- NULL

    })
  })

  output$data <- renderTable({

    dataSet <- mtcars

    invisible(lapply(aggregFilterObserver, function(filter){

      dataSet <<- dataSet[which(!(dataSet[[filter$col]] %in% filter$rows)), ]

    }))

    dataSet
  })
 }

shinyApp(ui = ui, server = server)