myRadioButtons.R

library(shiny)

myRadioButtons <- function (inputId, label=NULL, choices = NULL, selected = NULL, inline = FALSE, 
                            width = NULL, choiceNames = NULL, choiceValues = NULL) 
{
    args <- shiny:::normalizeChoicesArgs(choices, choiceNames, choiceValues)
    selected <- shiny:::restoreInput(id = inputId, default = selected)
    selected <- if (is.null(selected)) 
        args$choiceValues[[1]]
    else as.character(selected)
    if (length(selected) > 1) 
        stop("The 'selected' argument must be of length 1")
    options <- shiny:::generateOptions(inputId, selected, inline, "radio", 
                               args$choiceNames, args$choiceValues)
    divClass <- "form-group shiny-input-radiogroup shiny-input-container"
    if (inline) 
        divClass <- paste(divClass, "shiny-input-container-inline")
    if (!is.null(label)) {
        tags$div(id = inputId, style = if (!is.null(width)) 
            paste0("width: ", validateCssUnit(width), ";"), class = divClass, 
            controlLabel(inputId, label), options)        
    } else {
        tags$div(id = inputId, style = if (!is.null(width)) 
            paste0("width: ", validateCssUnit(width), ";"), class = divClass, 
            options)
    }
}

ui <- fluidPage(
    fluidRow(
        column(2, tags$strong('Radio Buttons')),
        column(10,
               myRadioButtons("radio",  
                            choices = list("Choice 1" = 1, "Choice 2" = 2, "Choice 3" = 3), 
                            selected = 1, inline = TRUE)  
               
        )        
    )
)

server <- function(input, output) {
}

shinyApp(ui, server)