我写了一个闪亮的应用程序，它允许用户生成和下载html rmarkdown报告。这行得通。
但是，在生成报告时，会提示用户输入保存位置。我当然可以在文件名中包含一个位置，但是仍然会提示用户。
理想情况下，我希望用户单击下载按钮，并将文件自动发送到特定位置。
这是一个可以运行的示例应用程序：
library(shiny)
shinyApp(
ui = fluidPage(
sliderInput("slider", "Slider", 1, 100, 50),
downloadButton("report", "Generate report"),
),
server = function(input, output) {
output$report <- downloadHandler(
# For PDF output, change this to "report.pdf"
filename = paste("My name", ".html", sep=""),
content = function(file) {
# Copy the report file to a temporary directory before processing it, in
# case we don't have write permissions to the current working dir
tempReport <- file.path(tempdir(), "report.Rmd")
file.copy("report.Rmd", tempReport, overwrite = TRUE)
# Set up parameters to pass to Rmd document
params <- list(n = input$slider)
# Knit the document, passing in the `params` list, and eval it in a
# child of the global environment (this isolates the code in the document
# from the code in this app).
rmarkdown::render(tempReport, output_file = file,
params = params,
envir = new.env(parent = globalenv())
)
}
)
}
)
和一个rmarkdown脚本：
---
title: "Dynamic report"
output: html_document
params:
n: NA
---
```{r}
# The `params` object is available in the document.
params$n
```
A plot of `params$n` random points.
```{r}
plot(rnorm(params$n), rnorm(params$n))
```