Ruby on rails dropdown <select> menu - how t

问题:

How can I create a colors dropdown menu in ruby on rails 3?

I know how to do it in html, css and javascript as following but i dont know how in ruby on rails 3.

Ideally using collection_select or collection_options_for_select other collection objects that build <select>'s and <options>'s. Using these would be preferred to manually looping through the collection and spitting out pieces and styling each piece though that could be done.

Code partial of what I am trying to get is:

<select>
<option value="">Highlight</option>
<option value="#000000" style="background-color: Black;color: #FFFFFF;">Black</option>
<option value="#808080" style="background-color: Gray;">Gray</option>
<option value="#A9A9A9" style="background-color: DarkGray;">DarkGray</option>

Full Code is at: http://pietschsoft.com/post/2004/09/20/Color-the-background-of-items-in-a-Dropdown-box-in-your-HTML-pages.aspx

回答1:

Rails Helper options_for_select absolutely allows you to provide styling information for individual options.

This is straight from the documentation of options_for_select

  options_for_select([ "Denmark", ["USA", {:class=>'bold'}], "Sweden" ], ["USA", "Sweden"])

gives

  <option value="Denmark">Denmark</option>\n<option value="USA" class="bold" selected="selected">USA</option>\n<option value="Sweden" selected="selected">Sweden</option>

and

  options_for_select([["Dollar", "$", {:class=>"bold"}], ["Kroner", "DKK", {:onclick => "alert('HI');"}]])

gives

  <option value="$" class="bold">Dollar</option>\n<option value="DKK" onclick="alert('HI');">Kroner</option>

And in your case it would be

options_for_select([["Black", {:style => "background-color: Black; color: #ffffff"}],
                    ["Gray", {:style => "background-color: Gray"}],
                    ["DarkGray", {:style => "backgorund-color: DarkGray"}]])

回答2:

The built in helpers don't support it as far as I know. However you can roll your own with:

def options_colors(colors)
  colors.collect do |color, code| 
    "<option value='#{code}' style='background-color:#{code};'>#{color}</option> "
  end.join
end

and then use it as follow:

@colors = ["Red" => "#f00", "Blue" => "blue"]
select_tag("setting[bg_color]", options_colors(@colors))