如何在 Shiny 中将图标添加到 downloadButton？答案

【问题标题】：How to add icon to downloadButton in Shiny?如何在 Shiny 中将图标添加到 downloadButton？
【发布时间】：2019-10-17 02:38:07
【问题描述】：

我可以在我的闪亮应用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"))

【问题讨论】：

标签： css r button shiny

【解决方案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。只需使用您自己的函数即可。

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中插入你想要的图标，然后像普通的下载按钮一样使用功能

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)

【讨论】：

谢谢，但是以前的标准图标呢。我可以删除它吗？ link

【解决方案2】：

我可能会建议为此使用shinyjs 包。您可以使用addCssClass() 函数快速将下载按钮上的字体真棒类更改为其他内容。

这是一个如何使用它的 css 选择器将默认下载图标更改为 pdf 文件图标的示例。;

shinyjs::addCssClass(selector = "i.fa.fa-download", class = 'fa fa-file-pdf')

不要忘记在您的 UI 中包含 useShinyjs()。

【讨论】：