R: Change the value of a slider input on the client

updateSliderInput {shiny} | R Documentation

## Change the value of a slider input on the client

### Description

Change the value of a slider input on the client

### Usage

    updateSliderInput(session, inputId, label = NULL, value = NULL,
      min = NULL, max = NULL, step = NULL)

### Arguments

`session` | The `session` object passed to function given to `shinyServer`.
`inputId` | The id of the input object.
`label` | The label to set for the input object.
`value` | The value to set for the input object.
`min` | Minimum value.
`max` | Maximum value.
`step` | Step size.

### 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

`sliderInput`

### Examples

    ## Only run this example in interactive R sessions
    if (interactive()) {
      shinyApp(
        ui = fluidPage(
          sidebarLayout(
            sidebarPanel(
              p("The first slider controls the second"),
              sliderInput("control", "Controller:", min=0, max=20, value=10,
                           step=1),
              sliderInput("receive", "Receiver:", min=0, max=20, value=10,
                           step=1)
            ),
            mainPanel()
          )
        ),
        server = function(input, output, session) {
          observe({
            val <- input$control
            # Control the value, min, max, and step.
            # Step size is 2 when input value is even; 1 when value is odd.
            updateSliderInput(session, "receive", value = val,
              min = floor(val/2), max = val+4, step = (val+1)%%2 + 1)
          })
        }
      )
    }

[Package shiny version 1.0.3 Index]