如何为R语言formattable表格的color_bar组件添加内边距

实现默认color_bar增加10px左右内边距有两种可行方案： #

方案1：最小改动CSS注入法

不需要修改原有核心逻辑，直接在你现有的htmlwidget链式调用中新增一行自定义CSS规则即可，代码如下：

FT %>%
  formattable() %>%
  as.htmlwidget() %>%
  # 新增这行CSS，给color_bar生成的带背景色的span设置左右10px内边距
  prependContent(tags$style(".formattable span[style*='background-color'] { padding: 0 10px !important; }")) %>%
  prependContent(tags$style("tr:nth-child(odd) {background-color: #e6e6e6 !important;}")) %>%
  prependContent(tags$style("tr:nth-child(even) {background-color: #999999 !important;}"))

注意：如果你的表格内还有其他带背景色的自定义span元素，这个方案会统一生效，若需要隔离效果请用方案2

方案2：自定义兼容官方参数的color_bar

封装一个和官方color_bar用法完全兼容的自定义函数，新增padding参数灵活配置内边距，代码如下：

# 自定义带内边距的color_bar，支持所有官方原生参数，新增padding设置左右内边距
color_bar_with_padding <- function(color = "lightgray", fun = "proportion", padding = "10px", ...) {
  fun <- match.fun(fun)
  formatter("span",
    style = function(x) {
      style(
        display = "inline-block",
        direction = "rtl",
        `border-radius` = "4px",
        `padding-left` = padding,
        `padding-right` = padding,
        `background-color` = csscolor(color),
        width = percent(fun(as.numeric(x), ...))
      )
    }
  )
}

使用时直接替换原有color_bar调用即可：

FT <- formattable(DF, align =c("l","c","r","c"), list(
  Name=formatter("span", 
                 style = x ~ ifelse(x == "Technology", style(font.weight = "bold"), NA)),
  Value = color_bar_with_padding("orange" , fun = unit.scale, padding = "10px"),
  Change = formatter("span", 
                     style = x ~ style(color = ifelse(x < 0 , "red", "green"), "font.size" = "18px"), 
                     x ~ icontext(ifelse(x < 0, "arrow-down", "arrow-up"), x)
  )),
  table.attr = 'class=\"table table-striped\" style="font-size: 18px; font-family: Calibri"')

内容的提问来源于stack exchange，提问作者JK Lambert