css - 如何在 Shiny 中为 downloadButton 添加图标？

Question

我可以在 Shiny 的应用程序中将自己的图标添加到 downloadButton 或 downloadBttn (shinyWidgets) 吗？

downloadBttn("downloadDataxlsx",
      label = "Download .xlsx", 
      style = "stretch",
      color = "primary",
      size = "md"))

Answer 1

> downloadButton
function (outputId, label = "Download", class = NULL, ...) 
{
    aTag <- tags$a(id = outputId, class = paste("btn btn-default shiny-download-link", 
        class), href = "", target = "_blank", download = NA, 
        icon("download"), label, ...)
}
<bytecode: 0x000000001a919c58>
<environment: namespace:shiny>

这是下载按钮背后的功能。只需使用您自己的功能即可。

customDownloadbutton <- function(outputId, label = "Download"){
    tags$a(id = outputId, class = "btn btn-default shiny-download-link", href = "", 
           target = "_blank", download = NA, icon("accessible-icon"), label)
}

只需在 icon 中插入您想要的图标，然后使用与普通下载按钮一样的功能

使用方法:

#

# This is a Shiny web application. You can run the application by clicking
# the 'Run App' button above.
#
# Find out more about building applications with Shiny here:
#
#    http://shiny.rstudio.com/
#

customDownloadbutton <- function(outputId, label = "Download"){
    tags$a(id = outputId, class = "btn btn-default shiny-download-link", href = "", 
           target = "_blank", download = NA, icon("accessible-icon"), label)
}

library(shiny)

# Define UI for application that draws a histogram
ui <- fluidPage(

   # Application title
   titlePanel("Old Faithful Geyser Data"),

   # Sidebar with a slider input for number of bins 
   sidebarLayout(
      sidebarPanel(
         sliderInput("bins",
                     "Number of bins:",
                     min = 1,
                     max = 50,
                     value = 30),
         customDownloadbutton("myDownloadButton")
      ),

      # Show a plot of the generated distribution
      mainPanel(
         plotOutput("distPlot")
      )
   )
)

# Define server logic required to draw a histogram
server <- function(input, output) {

   output$distPlot <- renderPlot({
      # generate bins based on input$bins from ui.R
      x    <- faithful[, 2] 
      bins <- seq(min(x), max(x), length.out = input$bins + 1)

      # draw the histogram with the specified number of bins
      hist(x, breaks = bins, col = 'darkgray', border = 'white')
   })
}

# Run the application 
shinyApp(ui = ui, server = server)