将 arguments 列表传递给 R Z3E751ABE1B5D0235C68CF279AD7 中的 function

Question

注意：我认识到之前已经询问过有关通过 function arguments 作为列表的类似问题，但大多数解决方案依赖于在 function 名称之前使用do.call并且我没有任何运气。

我有一个简单的仪表板，上面有两个盒子。 我想将下拉菜单参数存储为要在其他框中使用的列表。 我要存储的具体参数是： icon和width 。

以下是应用程序的工作版本，没有存储在列表中的下拉参数：

library(shiny)
library(shinydashboard)
library(shinyWidgets)

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(),
  dashboardBody(
    box(title = "Box 1",
        dropdownMenu = dropdown(icon = icon("cogs"), 
                                width = "400px",
                                label = "Plot Options Box 1",
                                numericInput(inputId = "box1", label = "Value", min = 1, max = 5, value = 3)
        )
    ),
    box(title = "Box 2",
        dropdownMenu = dropdown(icon = icon("cogs"), 
                                width = "400px",
                                label = "Plot Options Box 2",
                                numericInput(inputId = "box2", label = "Value", min = 1, max = 5, value = 3)
        )
    )
  )
)

server <- function(input, output) { }

shinyApp(ui, server)

我想做的是将盒子参数存储在这样的列表中：

box_params <- list(icon = icon("cogs"), 
                   width = "400px")

然后能够按照以下方式调用这些参数：

dropdown(box_params,
         label = "Plot Options Box 1",
         numericInput(inputId = "box1", label = "Value", min = 1, max = 5, value = 3))

Answer 1

使用do.call

do.call("dropdown", c(box_params, 
                      label = "Plot Options Box 1",
                      numericInput(inputId = "box1", 
      label = "Value", min = 1, max = 5, value = 3)))

- 完整代码

library(shiny)
library(shinydashboard)
library(shinyWidgets)
box_params <- list(icon = icon("cogs"), 
                   width = "400px")



ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(),
  dashboardBody(
    box(title = "Box 1",
        dropdownMenu = do.call("dropdown", c(box_params, list(label = "Plot Options Box 1",
                                                              numericInput(inputId = "box1", label = "Value", min = 1, max = 5, value = 3))))
    ),
    box(title = "Box 2",
        dropdownMenu = do.call("dropdown", c(box_params, list(label = "Plot Options Box 2",
                                                              numericInput(inputId = "box2", label = "Value", min = 1, max = 5, value = 3))))
    )
  )
)

server <- function(input, output) { }

shinyApp(ui, server)

-输出

Answer 2

这是一个实际呈现下拉菜单的版本（如@DJC 的示例代码所示， box() function 没有dropdownMenu参数）：

library(shiny)
library(shinydashboard)
library(shinyWidgets)

box_params <- list(icon = icon("cogs"), 
                   width = "400px")

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(),
  dashboardBody(
    box(title = "Box 1",
        do.call(dropdown, c(box_params, 
                            list(label = "Plot Options Box 1",
                                 numericInput(inputId = "box1", label = "Value", min = 1, max = 5, value = 3))))
    ),
    box(title = "Box 2",
        dropdown(
          icon = icon("cogs"), 
          width = "400px",
          label = "Plot Options Box 2",
          numericInput(inputId = "box2", label = "Value", min = 1, max = 5, value = 3)
          
        )
    )
  )
)

server <- function(input, output) {}

shinyApp(ui, server)

Answer 3

我会删除这个：但如果我这样做：

library(shiny)
library(shinydashboard)
library(shinyWidgets)

box_params <- list(icon = icon("cogs"), 
                   width = "400px")

ui <- dashboardPage(
  dashboardHeader(),
  dashboardSidebar(),
  dashboardBody(
    box(title = "Box 1",
        dropdownMenu = dropdown(box_params,
                                label = "Plot Options Box 1",
                                numericInput(inputId = "box1", label = "Value", min = 1, max = 5, value = 3)
        )
    ),
    box(title = "Box 2",
        dropdownMenu = dropdown(box_params,
                                label = "Plot Options Box 2",
                                numericInput(inputId = "box2", label = "Value", min = 1, max = 5, value = 3)
        )
    )
  )
)

server <- function(input, output) { }

shinyApp(ui, server)

我明白了：

所以这和@akrun的output是一样的吗？