r语言 - 在 Shiny 中导出 DiagrammeR，data.tree 到图像 (png)

Question

我正在尝试从Shiny App下载图像，该图像由DiagrammeR对象生成。

这是代码：

# Load packages
library(shinythemes)
library(DiagrammeR)
library(data.tree)
library(plotly)
library(shiny)
# Load data
data(acme)
# Define UI
ui <- fluidPage(theme = shinytheme("lumen"),
titlePanel("Paula trying II"),
sidebarLayout(
sidebarPanel(downloadButton(outputId = "dld_diagrama", label = "Download diagram")),
mainPanel(
grVizOutput("tree_plot", width = "100%", height = "760px")
)
)
)
# Define server function
server <- function(input, output) {
output$tree_plot <- renderGrViz({
plot(acme) 
})  
output$dld_diagrama <- downloadHandler(
filename = function(){
paste("diagram", "png", sep = ".")
},
content = function(file) {
plotly::export(tree_plot, file = "diagram.png")
}
)
}
# Create Shiny object
shinyApp(ui = ui, server = server)

这下载(有错误(一个.txt，显然是错误的。我正在尝试下载一个.png我也尝试过使用appshot但没有成功。

Answer 1

这是使用shiny的众多解决方案之一，您也可以将导出为png按钮

library(shinythemes)
library(DiagrammeR)
library(data.tree)
library(plotly)
library(shiny)
data(acme)
# Define UI
ui <- fluidPage(theme = shinytheme("lumen"),
titlePanel("Paula trying II"),
sidebarLayout(
sidebarPanel(downloadButton(outputId = "dld_diagrama", label = "Download diagram")),
mainPanel(
grVizOutput("tree_plot", width = "100%", height = "760px")
)
)
)
# Define server function
server <- function(input, output) {
input_plot <- reactive(plot(acme))
output$tree_plot <- renderGrViz({
input_plot() 
})  
output$dld_diagrama <- downloadHandler(
filename = function(){
paste("diagram", "html", sep = ".")
},
content = function(file) {
htmlwidgets::saveWidget(as_widget(input_plot()), file)
}
)
}
# Create Shiny object
shinyApp(ui = ui, server = server)

Answer 2

这有效：

# Load packages
library(shinythemes)
library(DiagrammeR)
library(data.tree)
library(plotly)
library(shiny)
# Load data
data(acme)
# Define UI
ui <- fluidPage(theme = shinytheme("lumen"),
titlePanel("Paula trying II"),
sidebarLayout(
sidebarPanel(downloadButton(outputId = "dld_diagrama", label = "Download diagram")),
mainPanel(
grVizOutput("tree_plot", width = "100%", height = "760px")
)
)
)
# Define server function
server <- function(input, output) {
input_plot <- reactive(plot(acme))
output$tree_plot <- renderGrViz({
plot(acme) 
})  
output$dld_diagrama <- downloadHandler(
filename = function(){
paste("diagram", "png", sep = ".")
},
content = function(file) {
htmlwidgets::saveWidget(as_widget(input_plot()), "www/diagrama.html", selfcontained = FALSE) 
webshot(url = "diagrama.html", delay = 5, file = file) 
}
)
}
# Create Shiny object
shinyApp(ui = ui, server = server)