View-in-excel-app.R

## app.R ##
server <- function(input, output) {
  # open the selected data set in excel on button trigger
  observeEvent(input$excel,{
  cat("...in open_this_reactive\n")
  data = paste(input$dataset, '.csv', sep='')
  cmd = paste0("open ", data)
  system(cmd)
# Original open.this function
#   open.this <-function(x, file = "__tmp.csv") {
#     write.table(x, file = file, sep = ",", row.names = TRUE, col.names = NA)
#     cmd = paste("open ", file, sep = "")
#     system(cmd)
#     cat("press enter to continue...\n")
#     scan()
#     cmd = paste("rm ", file, sep = "")
#     system(cmd)
#   }
#   open.this(iris)
  })
  
  datasetInput <- reactive({
    switch(input$dataset,
           "rock" = rock,
           "pressure" = pressure,
           "cars" = cars)
  })
  ########## Outputs ##############
  output$contents <- renderTable({
    
    # input$file1 will be NULL initially. After the user selects
    # and uploads a file, it will be a data frame with 'name',
    # 'size', 'type', and 'datapath' columns. The 'datapath'
    # column will contain the local filenames where the data can
    # be found.
    
    inFile <- input$file1
    
    if (is.null(inFile))
      return(NULL)
    
    read.csv(inFile$datapath, header=input$header, sep=input$sep, 
             quote=input$quote)
  })
  
  output$table <- renderTable({
    datasetInput()
  })
  
  output$downloadData <- downloadHandler(
    filename = function() { 
      paste(input$dataset, '.csv', sep='') 
    },
    content = function(file) {
      write.csv(datasetInput(), file)
    }
  )
}
#####################################
library(shinythemes)
ui <- fluidPage(theme = shinytheme("cosmo"),
  #titlePanel('Downloading & Uploading Data'),
  sidebarLayout(
    sidebarPanel(
      h3("Download"),
      selectInput("dataset", "Choose a dataset:", 
                  choices = c("rock", "pressure", "cars")),
      downloadButton('downloadData', 'Download'), 
      actionButton('excel', 'View in Excel'), 
      hr(),
      #######
      h3("Upload"),
      fileInput('file1', 'Choose CSV File',
                accept=c('text/csv', 
                         'text/comma-separated-values,text/plain', 
                         '.csv')),
      checkboxInput('header', 'Header', TRUE),
      radioButtons('sep', 'Separator',
                   c(Comma=',',
                     Semicolon=';',
                     Tab='\t'),
                   ','),
      radioButtons('quote', 'Quote',
                   c(None='',
                     'Double Quote'='"',
                     'Single Quote'="'"),
                   '"')
    ),
    mainPanel(
      fluidRow(
        column(6, h4("Download"),tableOutput('table')), 
        column(6, h4("Upload"),tableOutput('contents'))
      )
      
      
    )
  )
)
#####################################
shinyApp(ui = ui, server = server)