Change the value of a checkbox group input on the client — updateCheckboxGroupInput
R/update-input.R
Description
Change the value of a checkbox group input on the client
Arguments
- session
The
session
object passed to function given toshinyServer
. Default isgetDefaultReactiveDomain()
.- inputId
The id of the input object.
- label
The label to set for the input object.
- choices
List of values to show checkboxes for. If elements of the list are named then that name rather than the value is displayed to the user. If this argument is provided, then
choiceNames
andchoiceValues
must not be provided, and vice-versa. The values should be strings; other types (such as logicals and numbers) will be coerced to strings.- selected
The values that should be initially selected, if any.
- inline
If
TRUE
, render the choices inline (i.e. horizontally)- choiceNames, choiceValues
List of names and values, respectively, that are displayed to the user in the app and correspond to the each choice (for this reason,
choiceNames
andchoiceValues
must have the same length). If either of these arguments is provided, then the other must be provided andchoices
must not be provided. The advantage of using both of these over a named list forchoices
is thatchoiceNames
allows any type of UI object to be passed through (tag objects, icons, HTML code, ...), instead of just simple text. See Examples.
Details
The input updater functions send a message to the client, telling it to change the settings of an input object. The messages are collected and sent after all the observers (including outputs) have finished running.
The syntax of these functions is similar to the functions that created the
inputs in the first place. For example, numericInput()
and
updateNumericInput()
take a similar set of arguments.
Any arguments with NULL values will be ignored; they will not result in any changes to the input object on the client.
For radioButtons()
, checkboxGroupInput()
and
selectInput()
, the set of choices can be cleared by using
choices=character(0)
. Similarly, for these inputs, the selected item
can be cleared by using selected=character(0)
.
See also
Examples
## Only run examples in interactive R sessions
if (interactive()) {
ui <- fluidPage(
p("The first checkbox group controls the second"),
checkboxGroupInput("inCheckboxGroup", "Input checkbox",
c("Item A", "Item B", "Item C")),
checkboxGroupInput("inCheckboxGroup2", "Input checkbox 2",
c("Item A", "Item B", "Item C"))
)
server <- function(input, output, session) {
observe({
x <- input$inCheckboxGroup
# Can use character(0) to remove all choices
if (is.null(x))
x <- character(0)
# Can also set the label and select items
updateCheckboxGroupInput(session, "inCheckboxGroup2",
label = paste("Checkboxgroup label", length(x)),
choices = x,
selected = x
)
})
}
shinyApp(ui, server)
}