How can I display a tooltip on an HTML "option" tag?_问答_开发者

Either using plain HTML or jQuery assisted JavaScript, how do you display tooltips on individual <option> elements to aid the decision process (there开发者_高级运维 is not enough room for a different kind of control and some help will be needed).

Can this be done though a plug-in or similar?

I have tried a few tooltip plugins for jQuery with no success (including the one called Tooltip).

This solution should:

work in IE, WebKit as well as Gecko;
utilizing standard <select> wrapped <option> elements.

So if the solution wants to use other tags it should convert those elements into what it needs dynamically (and not expect the initial mark-up to be any different).

The code for this can be found here, it is under the SafeSurf section, where I want to display some help on rollover of the options as to the meaning of the choices. At present it can only be displayed "after the fact" and some upfront help for the user would be beneficial.

Appreciate that this is not easy and that something will probably need to be created - so the bounty will be awarded to the most complete solution or the specific hook that lands me closest to a solution I can create.

It seems in the 2 years since this was asked, the other browsers have caught up (at least on Windows... not sure about others). You can set a "title" attribute on the option tag:

<option value="" title="Tooltip">Some option</option>

This worked in Chrome 20, IE 9 (and its 8 & 7 modes), Firefox 3.6, RockMelt 16 (Chromium based) all on Windows 7

If increasing the number of visible options is available, the following might work for you:

<html>
    <head>
        <title>Select Option Tooltip Test</title>
        <script>
            function showIETooltip(e){
                if(!e){var e = window.event;}
                var obj = e.srcElement;
                var objHeight = obj.offsetHeight;
                var optionCount = obj.options.length;
                var eX = e.offsetX;
                var eY = e.offsetY;

                //vertical position within select will roughly give the moused over option...
                var hoverOptionIndex = Math.floor(eY / (objHeight / optionCount));

                var tooltip = document.getElementById('dvDiv');
                tooltip.innerHTML = obj.options[hoverOptionIndex].title;

                mouseX=e.pageX?e.pageX:e.clientX;
                mouseY=e.pageY?e.pageY:e.clientY;

                tooltip.style.left=mouseX+10;
                tooltip.style.top=mouseY;

                tooltip.style.display = 'block';

                var frm = document.getElementById("frm");
                frm.style.left = tooltip.style.left;
                frm.style.top = tooltip.style.top;
                frm.style.height = tooltip.offsetHeight;
                frm.style.width = tooltip.offsetWidth;
                frm.style.display = "block";
            }
            function hideIETooltip(e){
                var tooltip = document.getElementById('dvDiv');
                var iFrm = document.getElementById('frm');
                tooltip.innerHTML = '';
                tooltip.style.display = 'none';
                iFrm.style.display = 'none';
            }
        </script>
    </head>
    <body>
        <select onmousemove="showIETooltip();" onmouseout="hideIETooltip();" size="10">
            <option title="Option #1" value="1">Option #1</option>
            <option title="Option #2" value="2">Option #2</option>
            <option title="Option #3" value="3">Option #3</option>
            <option title="Option #4" value="4">Option #4</option>
            <option title="Option #5" value="5">Option #5</option>
            <option title="Option #6" value="6">Option #6</option>
            <option title="Option #7" value="7">Option #7</option>
            <option title="Option #8" value="8">Option #8</option>
            <option title="Option #9" value="9">Option #9</option>
            <option title="Option #10" value="10">Option #10</option>
        </select>
        <div id="dvDiv" style="display:none;position:absolute;padding:1px;border:1px solid #333333;;background-color:#fffedf;font-size:smaller;z-index:999;"></div>
        <iframe id="frm" style="display:none;position:absolute;z-index:998"></iframe>
    </body>
</html>

At least on firefox, you can set a "title" attribute on the option tag:

<option value="" title="Tooltip">Some option</option>

I just tried doing this on Chrome:

var $sel = $('#sel'); $sel.find('option').hover(function(){$sel.attr('title',$(this).attr('title'));console.log($(this).attr('title'))}, function(){$sel.attr('title','');});

However, the hover enter never fires... So you wouldn't be able to do this at all using the standard select. You could achieve this though through some non standard ways:

You could fake a select box by using radio boxes that look like dropdowns. So for example, have a radio box absolute positioned and opacity set to 0 placed over the styled box that is pretending to be the option.
Or you could use pure javascript and have a series of boxes and adding javascript onclick events to recreate the dropbox yourself - so you will update a hidden value with whichever box was clicked using javascript.
Or use one of the non standard libraries already out there. (If there are any?)

I don't think this would be possible to do across all browsers.

W3Schools reports that the option events exist in all browsers, but after setting up this test demo. I can only get it to work for Firefox (not Chrome or IE), I haven't tested it on other browsers.

Firefox also allows mouseenter and mouseleave but this is not reported on the w3schools page.

Update: Honestly, from looking at the example code you provided, I wouldn't even use a select box. I think it would look nicer with a slider. I've updated your demo. I had to make a few minor changes to your ratings object (adding a level number) and the safesurf tab. But I left pretty much everything else intact.

Why use a dropdown at all? The only way the user will see your explanatory text is by blindly hovering over one of the options.

I think it would be preferable to use a radio button group, and next to each item, put a tooltip icon indicating additional information, as well as displaying it after selection (like you currently have it).

I realize this doesn't exactly solve your problem, but I don't see the point in struggling with an html element that's notorious for its inflexibility when you could just use one that's better suited in the first place.

I don't believe that you can achieve this functionality with standard <select> element.

What i would suggest is to use such way.

http://filamentgroup.com/lab/jquery_ipod_style_and_flyout_menus/

The basic version of it won't take too much space and you can easily bind mouseover events to sub items to show a nice tooltip.

Hope this helps, Sinan.