Under the hood, shinyobjects
parses your code
and moves around the arguments of reactive and rendered objects so that
you can interact with them from the global environment. While not
required, this workflow works best with a static input
list
that shinyobjects
can help create. You can read more about
the benefits of creating a dummy input
list here
The main function, load_reactive_objects()
takes the
following steps:
parse the code that is active in the source pane or otherwise specified
.Rmd
files, apps with a server.R
file, or files using shinyServer()
, runApp()
,
or shinyApp()
keep library()
,
load()
, and assignment calls (<-
or
=
), everything else is discarded
rewrite the expressions:
for reactive(x = ...)
, the x
argument
is moved to the body of a function. For
eventReactive(event, valueExpr = ...)
it uses the
valueExpr
argument. Thus
becomes
Now that it is a function, you can view and manipulate
reactive_df()
for reactiveValues()
x <- reactiveValues(n = input$n)
becomes
x <- list(n = input$n)
for output
assignments
output$x <- renderPlot(expr)
becomes
output$x <- recordPlot(expr)
for all other output
assignments, the
expr
arguments are directly assigned
output$text <- renderText(paste("there are", input$n, "observations))
becomes
output$text <- (paste("there are", input$n, "observations))
evaluate the modified expressions into the specified environment, usually, the global environment
load_reactive_objects()
has options to restart your
R session and/or clear out your environment
There are two other functions:
convert_selection()
does a shorter version of these
steps using the code highlighted in the source pane view_ui()
works with UI components. It takes either the
html output in the console or selected code in the source pane and runs
a shiny app of just that object.