How to create a button that will create a pdf file of a table

Question

I currently have a table being generated and I would like the user to be able to create a pdf file when they click the download button.

I am currently getting an error where when I click the download button I get an html file that downloads the entire page of the app. I thought that using pdf(file) would work but it ignores the function.

Here is currently what I have.

library(shiny)
library(xlsx)
library(shinyWidgets)


population <- read.xlsx("population.xlsx", 1)

fieldsMandatory <- c("selectedCountry")

labelMandatory <- function(label) {
  tagList(
    label,
    span("*", class = "mandatory_star")
  )
}

appCSS <-
  ".mandatory_star {color: red;}"

ui <- fluidPage(
  
  navbarPage(title = span("Spatial Tracking of COVID-19 using Mathematical Models", style = "color:#000000; font-weight:bold; font-size:15pt"),
             
             tabPanel(title = "Model",
                      sidebarLayout(
                        sidebarPanel(
                          shinyjs::useShinyjs(),
                          shinyjs::inlineCSS(appCSS),
                          div(
                            id = "dashboard",
                            pickerInput(
                              inputId = "selectedCountry",
                              labelMandatory ("Country"), 
                              choices = population$Country,
                              multiple = FALSE,
                              options = pickerOptions(
                                actionsBox = TRUE,
                                title = "Please select a country")
                            ),
                            
                            sliderInput(inputId = "agg", 
                                        label = "Aggregation Factor", 
                                        min = 0, max = 50, step = 5, value = 10), 
                            
                            actionButton("go","Run Simulation"),
                         
                      )
                      
                ),
                mainPanel(
                  tabsetPanel(
                    tabPanel("Input Summary", verbatimTextOutput("summary"),
                             tableOutput("table"),
                             downloadButton(outputId = "downloadSummary", label = "Save Summary"))
                  )
                )
)
)
)
)

server <- function(input, output, session){
  
  observeEvent(input$resetAll, {
    shinyjs::reset("dashboard")
  })
  
  values <- reactiveValues()
  values$df <- data.frame(Variable = character(), Value = character()) 
  
  observeEvent(input$go, {
    
    
    row1 <- data.frame(Variable = "Country", Value = input$selectedCountry)
    row2 <- data.frame(Variable = "Aggregation Factor", Value = input$agg)
    
    values$df <- rbind(row1, row2)
    
  })
  
  output$table <- renderTable(values$df)
  
  observe({
    # check if all mandatory fields have a value
    mandatoryFilled <-
      vapply(fieldsMandatory,
             function(x) {
               !is.null(input[[x]]) && input[[x]] != ""
             },
             logical(1))
    mandatoryFilled <- all(mandatoryFilled)
    
    # enable/disable the submit button
    shinyjs::toggleState(id = "go", condition = mandatoryFilled)
  })
  
  output$downloadSummary <- downloadHandler(
    filename = function(file) {
      paste('my-report.pdf', )
    },
    
    content = function(file) {
      pdf(file)
    }
  )
  
  
}

shinyApp(ui,server)

score 0 · Answer 1 · answered Aug 18 '21 at 07:15

Here's a minimal example:

library(shiny)

ui <- fluidPage(
    downloadButton("savepdf", "Save pdf")
)

server <- function(input, output, session) {
    
    output$savepdf <- downloadHandler(
        filename = "test.pdf",
        content = function(file) {
            pdf(file)
            plot(iris$Sepal.Length, iris$Sepal.Width)
            dev.off()
        }
    )
}

shinyApp(ui, server)

Also see here.

score 0 · Answer 2 · answered Aug 18 '21 at 07:50

Here is a minimal example with the package latexpdf. It will create the pdf table in the folder of the app.

library(shiny)
library(latexpdf)

dat <- head(iris, 5)

ui <- fluidPage(
  br(),
  actionButton("dwnld", "Create pdf"),
  tableOutput("mytable")
)

server <- function(input, output, session){
  
  output[["mytable"]] <- renderTable({
    dat
  })
  
  observeEvent(input[["dwnld"]], {
    as.pdf(dat)
  })

}

shinyApp(ui, server)

How to create a button that will create a pdf file of a table

2 Answers2