Shiny downloadHandler 不保存 PNG 文件 [英] Shiny downloadHandler doesn't save PNG files

问题描述

我有我的下载功能来做所有的事情，当另存为屏幕出现时，我指定的文件名就会出现.当我点击保存窗口关闭，但没有文件被保存...

I've got my download function to do everything right, when the save as screen comes up, the file name I specified appears. When I click on save the window closes, but no file gets saved...

相同的绘图在应用程序中运行良好，唯一的问题是我似乎无法将其保存为 PNG 文件.

The same plot works fine in the app, the only problem is I cant seem to save it to a PNG file.

我在笔记本电脑上运行了 Shine 应用并使用了 RStudio.

I run the shine app on my laptop and use RStudio.

这是我的一些代码摘录.

Here is some extracts of my code.

ui.R

downloadButton('downloadSMemPlot', 'Download Graph')


server.R

'#draw membersip plot
s.MemPlotInput <- reactive({

'#some code to get data

s.MemPlot <- ggplot() + 
 geom_density(aes(x=Age, fill = Years), data=s.ben, alpha = 0.5) + 
 ggtitle("Density of beneficiary ages") + 
 theme_igray() + 
 theme(plot.title = element_text(lineheight=.8, face="bold")) +
 xlab("Age in full years") + ylab("Density")+
 scale_fill_hue()
})

output$s.memplot <- renderPlot({
  print(s.MemPlotInput())
})

'#download membership plot  
output$downloadSMemPlot <- downloadHandler(
  filename = "MembershipPlot.png",
  content = function(file) {
    png(file, type='cairo')
    print(s.MemPlotInput())
    dev.off()
  },
  contentType = 'application/png'
)

推荐答案

你想要

contentType = 'image/png'

不是

contentType = 'application/png'

虽然我不认为那是问题所在.您是在 RStudio 的预览窗格中还是在外部浏览器中运行它?使用预览窗格时，我在下载时遇到了同样的问题，但它在我的浏览器上运行良好.

Although I don't think that's the problem. Are you running it within RStudio's preview pane or in an external browser? I had the same problem with downloading when using the preview pane but it worked fine on my browser.

这篇关于Shiny downloadHandler 不保存 PNG 文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！