R: Change the value of a colour input

updateColourInput {colourpicker} | R Documentation

## Change the value of a colour input

### Description

Change the value of a colour input on the client.

### Usage

    updateColourInput(session, inputId, label = NULL, value = NULL,
      showColour = NULL, palette = NULL, allowedCols = NULL,
      allowTransparent = NULL, returnName = NULL)

### Arguments

`session` | The `session` object passed to function given to `shinyServer`.
`inputId` | The id of the colour input object.
`label` | The label to set for the input object.
`value` | The value to set for the input object.
`showColour` | Whether to show the chosen colour as text inside the input, as the background colour of the input, or both (default).
`palette` | The type of colour palette to allow the user to select colours from. `square` (default) shows a square colour palette that allows the user to choose any colour, while `limited` only gives the user a predefined list of colours to choose from.
`allowedCols` | A list of colours that the user can choose from. Only applicable when `palette == "limited"`. The `limited` palette uses a default list of 40 colours if `allowedCols` is not defined.
`allowTransparent` | If `TRUE`, enables a slider to choose an alpha (transparency) value for the colour. When a colour with opacity is chosen, the return value is an 8-digit HEX code.
`returnName` | If `TRUE`, then return the name of an R colour instead of a HEX value when possible.

### Details

The update function sends a message to the client, telling it to change the settings of a colour input object.
This function works similarly to the update functions provided by shiny.
Any argument with `NULL` values will be ignored.

### Note

See http://daattali.com/shiny/colourInput/ for a live demo.

### See Also

`colourInput`

### Examples

    if (interactive()) {
      library(shiny)
      shinyApp(
        ui = fluidPage(
          div("Selected colour:", textOutput("value", inline = TRUE)),
          colourInput("col", "Choose colour", "red"),
          h3("Update colour input"),
          textInput("text", "New colour: (colour name or HEX value)"),
          selectInput("showColour", "Show colour",
            c("both", "text", "background")),
          checkboxInput("allowTransparent", "Allow transparent", FALSE),
          checkboxInput("returnName", "Return R colour name", FALSE),
          actionButton("btn", "Update")
        ),
        server = function(input, output, session) {
          observeEvent(input$btn, {
            updateColourInput(session, "col",
              value = input$text, showColour = input$showColour,
              allowTransparent = input$allowTransparent,
              returnName = input$returnName)
          })
          output$value <- renderText(input$col)
        }
      )
    }

[Package colourpicker version 1.0 Index]