'Shiny' progress bar, but can run without reactive context

Usage

progress2(
  title,
  max = 1,
  ...,
  quiet = FALSE,
  session = shiny::getDefaultReactiveDomain(),
  shiny_auto_close = FALSE,
  log = NULL
)

Arguments

title: character, task description
max: maximum number of items in the queue
...: passed to shiny::Progress$new(...)
quiet: suppress console output, ignored in shiny context.
session: 'shiny' session, default is current reactive domain
shiny_auto_close: logical, automatically close 'shiny' progress bar once current observer is over. Default is FALSE. If setting to TRUE, then it's equivalent to p <- progress2(...); on.exit({p$close()}, add = TRUE).
log: function when running locally, default is NULL, which redirects to cat2

Value

A list of functions:

inc(detail, message = NULL, amount = 1, ...): Increase progress bar by amount (default is 1).
close(): Close the progress
reset(detail = '', message = '', value = 0): Reset the progress to value (default is 0), and reset information
get_value(): Get current progress value
is_closed(): Returns logical value if the progress is closed or not.

Examples


progress <- progress2('Task A', max = 2)
#> [Task A]: initializing... 

progress$inc('Detail 1')
#> [Task A]: Detail 1 (1 out of 2) 

progress$inc('Detail 2')
#> [Task A]: Detail 2 (2 out of 2) 

progress$close()
#> Finished 


# Check if progress is closed
progress$is_closed()
#> [1] TRUE

# ------------------------------ Shiny Example ------------------------------
library(shiny)
library(dipsaus)

ui <- fluidPage(
  actionButtonStyled('do', 'Click Here', type = 'primary')
)

server <- function(input, output, session) {
  observeEvent(input$do, {
    updateActionButtonStyled(session, 'do', disabled = TRUE)
    progress <- progress2('Task A', max = 10, shiny_auto_close = TRUE)
    lapply(1:10, function(ii){
      progress$inc(sprintf('Detail %d', ii))
      Sys.sleep(0.2)
    })
    updateActionButtonStyled(session, 'do', disabled = FALSE)
  })
}

if(interactive()){
  shinyApp(ui, server)
}