Intro to Shiny

making a shinyapp

Shinyapp example:weight tracking

download bottom

download csv:

################## In server.R:
output$downloadData <- downloadHandler(
  filename = function() {
    paste('data-', Sys.Date(), '.csv', sep='')
  },
  content = function(con) {
    write.csv(data, con)
  }
)

################### In ui.R:
downloadLink('downloadData', 'Download')

download excel:

library(writexl)
library(readxl)

################## In server.R:
output$downloadData <- downloadHandler(
  filename = function() {
    paste('data-', Sys.Date(), '.xlsx', sep='')
  },
  content = function(con) {
    write_xlsx(data, con)
  }
)

################### In ui.R:
downloadButton('downloadData', 'Download')

upload bottom

ui <- fluidPage(
  fileInput("upload", NULL, buttonLabel = "Upload...", multiple = TRUE)
  ,tableOutput("files_info")
  ,tableOutput("files")
)


server <- function(input, output, session) {
  
  output$files_info <- renderTable(input$upload)

  output$files <- renderTable(df <- read_excel(input$upload$datapath))
  
}

action bottom

  ################ action event

ui <- fluidPage(
  actionButton("go", "save data")
)


server <- function(input, output) {
  observeEvent(input$go, {
    data=read_excel(input$upload$datapath)
    write_xlsx(data,"Persion weight.xlsx")
    
  })

Host shinyapp in shiny.io

1. Go to https://www.shinyapps.io/ and setup a shinyapps account.And go to account page and copy Token and Secret

2. in Rstudio setup the www.shinyapps.io account

3. under your shiny current working directory and upload the shinyapp to shiny.io

getwd()
library(rsconnect)
deployApp()

Appendix

https://shiny.rstudio.com/

https://mastering-shiny.org/

https://docs.posit.co/shinyapps.io/getting-started.html