本章将重点介绍 Bootstrap 下拉菜单。下拉菜单是可切换的,是以列表格式显示链接的上下文菜单。这可以通过与 下拉菜单(Dropdown) JavaScript 插件 的互动来实现。
如需使用下拉菜单,只需要在 class .dropdown 内加上下拉菜单即可。下面的实例演示了基本的下拉菜单:
< div class = "dropdown" > < button type = "button" class = "btn dropdown-toggle" id = "dropdownMenu1" data-toggle = "dropdown" >主题 < span class = "caret" ></ span > </ button > < ul class = "dropdown-menu" role = "menu" aria-labelledby = "dropdownMenu1" > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >Java</ a > </ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >数据挖掘</ a > </ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >数据通信/网络</ a > </ li > < li role = "presentation" class = "divider" ></ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >分离的链接</ a > </ li > </ ul > </ div > |
结果如下所示:
通过向 .dropdown-menu 添加 class .pull-right 来向右对齐下拉菜单。下面的实例演示了这点:
< div class = "dropdown" > < button type = "button" class = "btn dropdown-toggle" id = "dropdownMenu1" data-toggle = "dropdown" >主题 < span class = "caret" ></ span > </ button > < ul class = "dropdown-menu pull-right" role = "menu" aria-labelledby = "dropdownMenu1" > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >Java</ a > </ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >数据挖掘</ a > </ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >数据通信/网络</ a > </ li > < li role = "presentation" class = "divider" ></ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >分离的链接</ a > </ li > </ ul > </ div > |
结果如下所示:
您可以使用 class dropdown-header 向下拉菜单的标签区域添加标题。下面的实例演示了这点:
< div class = "dropdown" > < button type = "button" class = "btn dropdown-toggle" id = "dropdownMenu1" data-toggle = "dropdown" >主题 < span class = "caret" ></ span > </ button > < ul class = "dropdown-menu" role = "menu" aria-labelledby = "dropdownMenu1" > < li role = "presentation" class = "dropdown-header" >下拉菜单标题</ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >Java</ a > </ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >数据挖掘</ a > </ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >数据通信/网络</ a > </ li > < li role = "presentation" class = "divider" ></ li > < li role = "presentation" class = "dropdown-header" >下拉菜单标题</ li > < li role = "presentation" > < a role = "menuitem" tabindex = "-1" href = "#" >分离的链接</ a > </ li > </ ul > </ div > |
结果如下所示:
类 | 描述 | 实例 |
---|---|---|
.dropdown | 指定下拉菜单,下拉菜单都包裹在 .dropdown 里 | 尝试一下 |
.dropdown-menu | 创建下拉菜单 | 尝试一下 |
.dropdown-menu-right | 下拉菜单右对齐 | 尝试一下 |
.dropdown-header | 下拉菜单中添加标题 | 尝试一下 |
.dropup | 指定向上弹出的下拉菜单 | 尝试一下 |
.disabled | 下拉菜单中的禁用项 | 尝试一下 |
.divider | 下拉菜单中的分割线 | 尝试一下 |