第1步：HTML文档
首先为你的导航创建一个无序列表，然后简单的写一下另外一个无序列表作为导航子菜单
1. class="topnav">
2. "#">Home</a></li>
3. <li>
4. "#">Tutorials</a>
5. class="subnav">
6. "#">Sub Nav Link</a></li>
7. "#">Sub Nav Link</a></li>
8. </ul>
9. </li>
10. <li>
11. "#">Resources</a>
12. class="subnav">
13. "#">Sub Nav Link</a></li>
14. "#">Sub Nav Link</a></li>
15. </ul>
16. </li>
17. "#">About Us</a></li>
18. "#">Advertise</a></li>
19. "#">Submit</a></li>
20. "#">Contact Us</a></li>
21. </ul>
<ul class="topnav">
<li><a href="#">Home</a></li>
<li>
<a href="#">Tutorials</a>
<ul class="subnav">
<li><a href="#">Sub Nav Link</a></li>
<li><a href="#">Sub Nav Link</a></li>
</ul>
</li>
<li>
<a href="#">Resources</a>
<ul class="subnav">
<li><a href="#">Sub Nav Link</a></li>
<li><a href="#">Sub Nav Link</a></li>
</ul>
</li>
<li><a href="#">About Us</a></li>
<li><a href="#">Advertise</a></li>
<li><a href="#">Submit</a></li>
<li><a href="#">Contact Us</a></li>
</ul>
第2步：CSS
然后定义导航样式
1. ul.topnav {
2. list-style: none;
3. padding: 0 20px;
4. margin: 0;
5. float: left;
6. width: 920px;
7. background: #222;
8. font-size: 1.2em;
9. background: url(topnav_bg.gif) repeat-x;
10. }
11. ul.topnav li {
12. float: left;
13. margin: 0;
14. padding: 0 15px
15. position: relative; /*--Declare X and Y axis base for sub navigation--*/
16. }
17. ul.topnav li a{
18. padding: 10px 5px;
19. color: #fff;
20. display: block;
21. text-decoration: none;
22. float: left;
23. }
24. ul.topnav li a:hover{
25. background: url(topnav_hover.gif) no-repeat center top;
26. }
27. /*--Drop down trigger styles--*/
28. width: 17px;
29. height: 35px;
30. float: left;
31. background: url(subnav_btn.gif) no-repeat center top;
32. }
33. ul.topnav li span.subhover
34. background-position: center bottombottom; cursor: pointer;}
35. /*--Hover effect for trigger--*/
36. ul.topnav li ul.subnav {
37. list-style: none;
38. position: absolute;
39. /*--Important - Keeps subnav from affecting main navigation flow--*/
40. left: 0; top: 35px;
41. background: #333;
42. margin: 0; padding: 0;
43. display: none;
44. float: left;
45. width: 170px;
46. border: 1px solid #111;
47. }
48. ul.topnav li ul.subnav li{
49. margin: 0; padding: 0;
50. border-top: 1px solid #252525; /*--Create bevel effect--*/
51. border-bottom: 1px solid #444; /*--Create bevel effect--*/
52. clear: both;
53. width: 170px;
54. }
55. html ul.topnav li ul.subnav li a {
56. float: left;
57. width: 145px;
58. background: #333 url(dropdown_linkbg.gif) no-repeat 10px center;
59. padding-left: 20px;
60. }
61. /*--Hover effect for subnav links--*/
62. background: #222 url(dropdown_linkbg.gif) no-repeat 10px center;
63. }
ul.topnav {
list-style: none;
padding: 0 20px;
margin: 0;
float: left;
width: 920px;
background: #222;
font-size: 1.2em;
background: url(topnav_bg.gif) repeat-x;
}
ul.topnav li {
float: left;
margin: 0;
padding: 0 15px 0 0;
position: relative; /*--Declare X and Y axis base for sub navigation--*/
}
ul.topnav li a{
padding: 10px 5px;
color: #fff;
display: block;
text-decoration: none;
float: left;
}
ul.topnav li a:hover{
background: url(topnav_hover.gif) no-repeat center top;
}
ul.topnav li span { /*--Drop down trigger styles--*/
width: 17px;
height: 35px;
float: left;
background: url(subnav_btn.gif) no-repeat center top;
}
ul.topnav li span.subhover {background-position: center bottom; cursor: pointer;}/*--Hover effect for trigger--*/
ul.topnav li ul.subnav {
list-style: none;
position: absolute;/*--Important - Keeps subnav from affecting main navigation flow--*/
left: 0; top: 35px;
background: #333;
margin: 0; padding: 0;
display: none;
float: left;
width: 170px;
border: 1px solid #111;
}
ul.topnav li ul.subnav li{
margin: 0; padding: 0;
border-top: 1px solid #252525; /*--Create bevel effect--*/
border-bottom: 1px solid #444; /*--Create bevel effect--*/
clear: both;
width: 170px;
}
html ul.topnav li ul.subnav li a {
float: left;
width: 145px;
background: #333 url(dropdown_linkbg.gif) no-repeat 10px center;
padding-left: 20px;
}
html ul.topnav li ul.subnav li a:hover { /*--Hover effect for subnav links--*/
background: #222 url(dropdown_linkbg.gif) no-repeat 10px center;
}第3步：jQuery
下面的脚本包含的内容解释了JQuery将要执行的的动作，你是jQuery新手？看这里.
1. function(){
2.
3. "ul.subnav").parent().append("<span></span>"); //Only shows drop down trigger when js is enabled
(Adds empty span tag after ul.subnav*)
1.
2. "ul.topnav li span").click(function() { //When trigger is clicked...
3.
4. //Following events are applied to the subnav itself (moving subnav up and down)
5. this).parent().find("ul.subnav").slideDown('fast').show();
6. //Drop down the subnav on click
7.
8. this).parent().hover(function() {
9. function(){
10. this).parent().find("ul.subnav").slideUp('slow'); //When the mouse hovers out of the subnav, move it back up
11. });
12.
13. //Following events are applied to the trigger (Hover events for the trigger)
14. function() {
15. this).addClass("subhover"); //On hover over, add class "subhover"
16. function(){ //On Hover Out
17. this).removeClass("subhover"); //On hover out, remove class "subhover"
18. });
19.
20. });
$(document).ready(function(){
$("ul.subnav").parent().append("<span></span>");
//Only shows drop down trigger when js is enabled (Adds empty span tag after ul.subnav*)
$("ul.topnav li span").click(function() { //When trigger is clicked...
//Following events are applied to the subnav itself (moving subnav up and down)
$(this).parent().find("ul.subnav").slideDown('fast').show();
//Drop down the subnav on click
$(this).parent().hover(function() {
}, function(){
$(this).parent().find("ul.subnav").slideUp('slow');
//When the mouse hovers out of the subnav, move it back up
});
//Following events are applied to the trigger (Hover events for the trigger)
}).hover(function() {
$(this).addClass("subhover"); //On hover over, add class "subhover"
}, function(){ //On Hover Out
$(this).removeClass("subhover"); //On hover out, remove class "subhover"
});
});
下拉菜单只是在支持javascript的的情况下才会显示并触发。
