checkboxGroupArrayInput: Checkbox Group Input Control (Array Layout)
In jayemerson/ShinyHelper: Making Shiny Application Creation Easier (maybe)

Description Usage Arguments Value Author(s) See Also Examples

Create an array of checkboxes that can be used to toggle multiple choices independently. The server will receive the input as a character vector of the selected values.

  checkboxGroupArrayInput(inputId, label, choices,
    selected = NULL, ncol = 3)
  checkboxGroupArrayInputAdd(inputId, label, choices,
    selected = NULL, ncol = 3)

`inputId`	Input variable to assign the control's value to.
`label`	Display label for the control.
`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.
`selected`	Names of items that should be initially selected, if any.
`ncol`	Number of columns to use for the array of checkboxes.

A list of HTML elements that can be added to a UI definition.

Jay Emerson, but a direct modification of the original function checkboxGroupInput() of package shiny.

checkboxInput, updateCheckboxGroupInput

checkboxGroupArrayInput("variable", "Variable:",
                        c("Cylinders" = "cyl",
                          "Transmission" = "am",
                          "Gears" = "gear"), ncol = 2)