e.observe.event: Observe Event with Error Handling
In devOpifex/erratum: Handle Error and Warning Messages

View source: R/shiny.R

e.observe.event

R Documentation

Observe Event with Error Handling

Description

Observe event with erratum error handling.

Usage

e.observe.event(
  eventExpr,
  handlerExpr,
  e = NULL,
  w = NULL,
  event.env = parent.frame(),
  event.quoted = FALSE,
  handler.env = parent.frame(),
  handler.quoted = FALSE,
  ...,
  label = NULL,
  suspended = FALSE,
  priority = 0,
  domain = shiny::getDefaultReactiveDomain(),
  autoDestroy = TRUE,
  ignoreNULL = TRUE,
  ignoreInit = FALSE,
  once = FALSE
)

Arguments

`eventExpr`	A (quoted or unquoted) expression that represents the event; this can be a simple reactive value like `input$click`, a call to a reactive expression like `dataset()`, or even a complex expression inside curly braces
`handlerExpr`	The expression to call whenever `eventExpr` is invalidated. This should be a side-effect-producing action (the return value will be ignored). It will be executed within an `isolate()` scope.
`e`	Error handler.
`w`	Warning handler.
`event.env`	The parent environment for the reactive expression. By default, this is the calling environment, the same as when defining an ordinary non-reactive expression. If `eventExpr` is a quosure and `event.quoted` is `TRUE`, then `event.env` is ignored.
`event.quoted`	If it is `TRUE`, then the `quote()`ed value of `eventExpr` will be used when `eventExpr` is evaluated. If `eventExpr` is a quosure and you would like to use its expression as a value for `eventExpr`, then you must set `event.quoted` to `TRUE`.
`handler.env`	The parent environment for the reactive expression. By default, this is the calling environment, the same as when defining an ordinary non-reactive expression. If `handlerExpr` is a quosure and `handler.quoted` is `TRUE`, then `handler.env` is ignored.
`handler.quoted`	If it is `TRUE`, then the `quote()`ed value of `handlerExpr` will be used when `handlerExpr` is evaluated. If `handlerExpr` is a quosure and you would like to use its expression as a value for `handlerExpr`, then you must set `handler.quoted` to `TRUE`.
`...`	Currently not used.
`label`	A label for the observer or reactive, useful for debugging.
`suspended`	If `TRUE`, start the observer in a suspended state. If `FALSE` (the default), start in a non-suspended state.
`priority`	An integer or numeric that controls the priority with which this observer should be executed. An observer with a given priority level will always execute sooner than all observers with a lower priority level. Positive, negative, and zero values are allowed.
`domain`	See domains.
`autoDestroy`	If `TRUE` (the default), the observer will be automatically destroyed when its domain (if any) ends.
`ignoreNULL`	Whether the action should be triggered (or value calculated, in the case of `eventReactive`) when the input event expression is `NULL`. See Details.
`ignoreInit`	If `TRUE`, then, when this `observeEvent` is first created/initialized, ignore the `handlerExpr` (the second argument), whether it is otherwise supposed to run or not. The default is `FALSE`. See Details.
`once`	Whether this `observeEvent` should be immediately destroyed after the first time that the code in `handlerExpr` is run. This pattern is useful when you want to subscribe to a event that should only happen once.