javascript - DT 表中的 Shiny 小部件

Question

我正在尝试在 DT 表的行中包含 Shiny 的小部件，例如 textInput、selectInput(单个)、sliderInput 和 selectInput(多个)。当小部件直接放在页面上时，它们会正确显示，但是当它们放在表格中时，其中一些不会正确显示。

textInput 很好，selectInput(单个)除了一些 css 差异外大部分都很好，但是 selectInput(多个)显示不正确，sliderInput 肯定显示不正确。似乎依赖 javascript 的小部件是有问题的。有没有办法让这些widgets在DT表中正常工作？

这是我的可重现示例。在将小部件放入表中时，我使用了小部件的原始 HTML，但我直接从每个小部件的 shiny 函数生成的 HTML 中获取了它。

library(shiny)
library(DT)

ui <- fluidPage(
  h3("This is how I want the widgets to look in the DT table."),
  fluidRow(column(3, textInput(inputId = "text",
                               label = "TEXT")),
           column(3, selectInput(inputId = "single_select",
                                 label = "SINGLE SELECT",
                                 choices = c("", "A", "B", "C"))),
           column(3, sliderInput(inputId = "slider",
                                 label = "SLIDER",
                                 min = 0,
                                 max = 10,
                                 value = c(0, 10))),
           column(3, selectizeInput(inputId = "multiple_select",
                                    label = "MULTIPLE SELECT",
                                    choices = c("", "A", "B", "C"),
                                    multiple = TRUE))),
  h3("This is how they actually appear in a DT table."),
  fluidRow(DTOutput(outputId = "table"))
)

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

  output$table <- renderDT({
    data <- data.frame(ROW = 1:5,
                       TEXT = '<input id="text" type="text" class="form-control" value=""/>',
                       SINGLE_SELECT = '<select id="single_select" style="width: 100%;">
                                          <option value="" selected></option>
                                          <option value="A">A</option>
                                          <option value="B">B</option>
                                          <option value="C">C</option>
                                        </select>',
                       SLIDER = '<input class="js-range-slider" id="slider" data-type="double" data-min="0" data-max="10" data-from="0" data-to="10" data-step="1" data-grid="true" data-grid-num="10" data-grid-snap="false" data-prettify-separator="," data-prettify-enabled="true" data-keyboard="true" data-drag-interval="true" data-data-type="number"/>',
                       MULTIPLE_SELECT = '<select id="multiple_select" class="form-control" multiple="multiple">
                                            <option value=""></option>
                                            <option value="A">A</option>
                                            <option value="B">B</option>
                                            <option value="C">C</option>
                                          </select>',
                       stringsAsFactors = FALSE)

    datatable(data = data,
              selection = "none",
              escape = FALSE,
              rownames = FALSE)
  })

}

shinyApp(ui = ui, server = server)

Answer 1

slider

对于 slider ，您必须从文本输入开始:

SLIDER = '<input type="text" id="s" name="slider" value="" />'

然后用 JavaScript 把它变成一个 slider :

js <- c(
  "function(settings){",
  "  $('#s').ionRangeSlider({",
  "    type: 'double',",
  "    grid: true,",
  "    grid_num: 10,",
  "    min: 0,",
  "    max: 20,",
  "    from: 5,",
  "    to: 15",
  "  });",
  "}"
)

参见 ionRangeSlider对于选项。

您可以使用 initComplete 选项传递 JavaScript 代码:

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

  output$table <- renderDT({
    data <- data.frame(ROW = 1:5,
                       TEXT = '<input id="text" type="text" class="form-control" value=""/>',
                       SINGLE_SELECT = '<select id="single_select" style="width: 100%;">
                       <option value="" selected></option>
                       <option value="A">A</option>
                       <option value="B">B</option>
                       <option value="C">C</option>
                       </select>',
                       SLIDER = '<input type="text" id="s" name="slider" value="" />',
                       MULTIPLE_SELECT = '<select id="multiple_select" class="form-control" multiple="multiple">
                       <option value=""></option>
                       <option value="A">A</option>
                       <option value="B">B</option>
                       <option value="C">C</option>
                       </select>',
                       stringsAsFactors = FALSE)

    datatable(data = data,
              selection = "none",
              escape = FALSE,
              rownames = FALSE, 
              options = 
                list(
                  initComplete = JS(js)
                ))
  })

}

然后你只得到第一行的 slider :

那是因为五个文本输入具有相同的 id。您必须为五个文本输入设置不同的 ID:

SLIDER = sapply(1:5, function(i) {
  sprintf('<input type="text" id="Slider%d" name="slider" value="" />', i)
}),

然后使用这段 JavaScript 代码将它们变成 slider :

js <- c(
  "function(settings){",
  "  $('[id^=Slider]').ionRangeSlider({",
  "    type: 'double',",
  "    grid: true,",
  "    grid_num: 10,",
  "    min: 0,",
  "    max: 20,",
  "    from: 5,",
  "    to: 15",
  "  });",
  "}"
)

要设置 from 和 to 的初始值，最好将它们放在输入文本的 value 参数中，如下所示:

SLIDER = sapply(1:5, function(i) {
  sprintf('<input type="text" id="Slider%d" name="slider" value="5;15" />', i)
})

js <- c(
  "function(settings){",
  "  $('[id^=Slider]').ionRangeSlider({",
  "    type: 'double',",
  "    grid: true,",
  "    grid_num: 10,",
  "    min: 0,",
  "    max: 20",
  "  });",
  "}"
)

多选

要获得所需的多选显示，您必须调用 selectize():

MULTIPLE_SELECT = '<select id="mselect" class="form-control" multiple="multiple">
                       <option value=""></option>
                       <option value="A">A</option>
                       <option value="B">B</option>
                       <option value="C">C</option>
                    </select>'
js <- c(
  "function(settings){",
  "  $('[id^=Slider]').ionRangeSlider({",
  "    type: 'double',",
  "    grid: true,",
  "    grid_num: 10,",
  "    min: 0,",
  "    max: 20",
  "  });",
  "  $('#mselect').selectize()",
  "}"
)

同样，这仅适用于第一个多选。使用个人 ID 申请这五个。

绑定(bind)

最后，您必须绑定(bind)输入以获得它们在 Shiny 中可用的值:

datatable(data = data,
          selection = "none",
          escape = FALSE,
          rownames = FALSE, 
          options = 
            list(
              initComplete = JS(js),
              preDrawCallback = JS('function() { Shiny.unbindAll(this.api().table().node()); }'),
              drawCallback = JS('function() { Shiny.bindAll(this.api().table().node()); } ')
            )
)

现在您可以获取 input$Slider1、input$Slider2、... 和 input$mselect 中的值。请注意，input$Slider[1/2/3/4/5] 以这种格式返回 slider 的值:"3;15"。