如何在rmarkdown文档中自定义下载handler-button

Question

在Shiny a 中，下载Handler与actionbutton/下载button在UI-Part中。因此，您可以轻松地通过键入来更改按钮标签：

downloadButton("btn_export", "Export")

这里有一点ShinyApp，只需一个按钮即可导出一些示例数据：

library(shiny)

ui <- fluidPage(
    downloadButton("btn_export", "Export")
)

server <- function(input, output) {
    data <- mtcars
    
    output$btn_export <- downloadHandler(
        filename = function() {
            paste0("shiny_", Sys.Date(), ".csv")
        },
        content = function(file) {
            write.csv(data, file)
        }
    )
}

shinyApp(ui, server)

在rmarkDown中，下载handler直接添加到代码块：

```{r, echo=FALSE}
downloadHandler(
  filename = function() {
    paste0("rmd_", Sys.Date(), ".csv")
  },
  content = function(file) {
    write.csv(data, file)
  }
)
``` 

我如何更改下载按钮的标签？

一个完整的示例：

---
title: "test"
runtime: shiny
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r data_prep, include=FALSE}
data <- mtcars
```

```{r download, echo=FALSE}
downloadHandler(
  filename = function() {
    paste0("rmd_", Sys.Date(), ".csv")
  },
  content = function(file) {
    write.csv(data, file)
  }
)
```

编辑：

上部可再现的最小示例可能太小了。 下载Handler在我的真实rmarkDown文档中正在渲染静态RMD报告供下载：

downloadHandler(filename = function() {
    return("CaRe.html")
  }, content = function(file) {
     rmarkdown::render(input = "CaRe_static.Rmd", 
                       output_file = file,
                       params = list(in_rohdaten = input$in_rohdaten$datapath,
                                     in_kunde = input$in_kunde,
                                     in_kampagne = input$in_kampagne,
                                     in_auftrag = input$in_auftrag,
                                     in_datum = input$in_datum
     ))
  }, contentType = "text/html"
)

以防该解决方案相关。

Answer 1

grh，如果您仔细阅读手册，那就太简单了。对不起，浪费了时间。

您可以使用outputargs 的参数下载handler来更改下载按钮的标签：

---
title: "test"
runtime: shiny
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r data_prep, include=FALSE}
data <- mtcars
```

```{r download, echo=FALSE}
downloadHandler(
  filename = function() {
    paste0("rmd_", Sys.Date(), ".csv")
  },
  content = function(file) {
    write.csv(data, file)
  },
  outputArgs = list(label = "Export")  # <--- That's it!
)
```

Answer 2

不确定如何使用downloadhandler（）进行操作，但是您可以尝试下载软件包。

---
title: "test"
runtime: shiny
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```

```{r, include=FALSE}
library(downloadthis)

data <- mtcars
```

```{r, echo=FALSE}
download_this(mtcars,
  output_name = "mtcars data set",
  output_extension = ".csv",
  button_label = "Download mtcars",
  button_type = "warning",
  has_icon = TRUE,
  icon = "fa fa-save"
)