Joomla! Documentation™

Joomla2.5以上的替代布局方法介绍。 Joomla! 1.5 引入概念 覆盖核心布局 使用模板覆盖系统。Joomla !版本2.5引入了一组特性，使站点管理员能够更多地控制文章、联系人、新闻提要和Web链接的显示。可供选择的布局有四种:

1. 模块
2. 组件
3. 分类
4. 菜单项目

替代布局与模板覆盖功能类似，但允许您有更多的控制选择。下面讨论每种类型。

模块替代布局 为模块创建另一个布局类似于为模块创建模板覆盖。在这两种情况下，都创建了一个名为templates/<your template>/html/<module name>.的文件夹。例如文这样命名："mod_login"是对beez5模板的模板覆盖或替代布局将是 templates/beez5/html/mod_login/.

模板覆盖和另一个布局之间有两个重要的区别。第一个是文件名。对于模板覆盖，您将调用该文件 default.php 匹配核心文件名。对于另一个布局，使用不同的名称。唯一的规则是“文件名不应该有任何下划线”。这允许您拥有包含多个文件的复杂布局。要调用的初始文件是没有下划线的，并且从这个初始文件中调用的任何其他文件都将以这个名称下划线。例如，您可以调用最初的文件mynewlogin.php 关联mynewlogin_1.php.

第二个重要的区别是，与模板覆盖文件不同，当模块使用该模板显示模块时，它会自动被调用，另一个布局文件只有在模块管理器中作为参数选择时才会调用。在版本2.5和之后的版本中，有一个新的参数被称为替代布局，如下所示。

File:Screenshot override tutorial 20110107-01-英文.png

此参数将列出您在此模块的模板文件夹中放置的任何文件(没有下划线)。您还可以使用模板的系统语言文件来翻译文件名。例如，如果你添加了这条线。

TPL_BEEZ5_MOD_LOGIN_LAYOUT_NOLOGIN="Alt Login Layout"

到 en-GB.tpl_beez5.sys.ini它将转换文件名nologin.php到“登录布局”

重要的是要理解，如果在模块管理器屏幕中指定，模块的另一个布局文件将被用于该模块，而不考虑使用什么模板来显示模块所显示的页面。因此，管理员有责任确保在显示该模块的任何模板中，布局文件都能正常工作。

Component Alternative Layouts

Component alternative layouts work similarly to module layouts discussed above. Again, a file is placed in the same folder where you place a template override file. For example, to create an alternative layout for an article for the template "beez5", you would put a file in the folder templates/beez5/html/com_content/article/. As with module layouts, the file must not be named the same as the core file and must not include underscores in the name. Additionally, there should not be an XML file of the same name in this folder. (We'll discuss XML files below under Menu Item Alternative Layouts.)

You can set a global value for component layouts in the Options window of the component. For example, in the Article Manager Options window, there is a parameter for Alternative Layout as shown below:

This will create a global value that individual components (articles, contacts, news feeds and Web links) can inherit from.

As with module layouts, the component layouts are shown as parameter options in the individual component edit screen. For example, for an article, the parameter shows in the Article Options group as shown below.

As with other parameters, the Use Global setting will use the setting from the Options parameter. The From Component's Default setting will use the component's default layout. Alternative layouts that you have created for different templates are shown under each template heading.

File names may be translated. The line below:

TPL_BEEZ5_COM_CONTENT_ARTICLE_LAYOUT_MYLAYOUT="Title Only No XML"

will translate a file called "mylayout.php" as "Title Only No XML".

You can have more than one file for a layout. The initial file must be named without underscores and any additional files must have underscores.

Component alternative layouts may be used with articles, contacts, or news feeds. Web links don't have a single-component layout so no alternative layout is available for Web links.

Component alternative layouts are only used when two conditions are met: (1) they are specified in the component parameters; and (2) there is no menu item for this specific component. For example, if you have one or more menu items of type "Single Article" set up for a given article, then the alternative layout for that article will not be used. Instead, the layout specified in the menu item will be used. This is consistent with the general way that component parameters work, where the most specific (in this case a single-article menu item) overrides the less specific (in this case, the article parameters).

Category Alternative Layouts

Category alternative layouts work identically to component layouts. The rules for specifying layout files are the same. The only difference is that the folder is the category folder, not the component folder. For example, a contact category alternative layout for beez5 would go in the folder templates/beez5/html/com_contact/category.

You can set category layouts globally, in the Options screen of each component. Below is an example from the Contact Manager Options screen:

Category alternative layouts show up when you add or edit a category in the Category Manager under the Basic Options as shown below.

Category alternative layouts may be used for articles, contacts, news feeds and Web links.

As with component layouts, category layouts only will show if (1) they are specified for the category in the global or category parameters and (2) there is no menu item specifically for this category (for example, List Contacts in a Category, List News feeds in a Category, List Web links in a Category, Category List, Category Blog).

If there is a menu item set up for this specific category, that layout will be used instead of the alternative category layout.

Drill Down to Blog or List

For articles, we have two core layouts available: Blog and List. Both of these options show under the "From Component" heading in the layout parameters for article category. So, like other layout options, you can now select Blog or List for categories either globally (in the Article Manager Options, shown below), or when editing a single article category.

This means that, like other layout options, you can control whether article category links drill down to blog or list layouts. It is important to understand that, like other layout parameters, this option will only take effect when there is no single-category menu item for the category.

Alternative Menu Items

Alternative Menu Items have one important difference with the others. To create a menu item alternative layout, you must include an XML file whose name matches the initial layout file. For example, to create an alternative menu item called "myarticle" for an article in the beez5 template, you would create two files in the templates/beez5/html/com_content/article folder called myarticle.php and myarticle.xml. If you wanted to include more layout files, you would add these files with underscores in the file names.

The XML file uses the same format as the core Menu Item XML files. This allows you not only to create a customized layout for this menu item but also allows you to create customized parameters. For example, you could hide some parameters or add new parameters.

Alternative Menu Items show up when you select a menu item type in the Menu Manager as shown below.

Alternative Menu Items are used and work the same way as standard menu items. Since they are already based on customized layouts, template overrides do not apply to alternative menu items.

As indicated above, menu item layouts take priority over component or category alternative layouts.

Translation of alternative menu items is done with the following tags in the XML files. The format is "TPL_"<template name>_<component>_<view>_<menu item name>_<tag type>. For example, these lines below will translate the title, option, and description for an alternative menu item called "catmenuitem".

TPL_BEEZ5_COM_CONTENT_CATEGORY_VIEW_CATMENUITEM_TITLE="Beez5 Custom Category Layout"
TPL_BEEZ5_COM_CONTENT_CATEGORY_VIEW_CATMENUITEM_OPTION="Beez5 Custom"
TPL_BEEZ5_COM_CONTENT_CATEGORY_VIEW_CATMENUITEM_DESC="Description for beez5 custom category layout."

These strings have to be added to language/en-GB/en-GB.tpl_beez5.sys.ini

The catmenuitem.xml would start with:

<?xml version="1.0" encoding="utf-8"?>
<metadata>
   <layout title="TPL_BEEZ5_COM_CONTENT_CATEGORY_VIEW_CATMENUITEM_TITLE" option="TPL_BEEZ5_COM_CONTENT_CATEGORY_VIEW_CATMENUITEM_OPTION">
      <help
         key = "JHELP_MENUS_MENU_ITEM_ARTICLE_SINGLE_ARTICLE"
      />
      <message>
         <![CDATA[TPL_BEEZ5_COM_CONTENT_CATEGORY_VIEW_CATMENUITEM_DESC]]>
      </message>
   </layout>

Controlling the Template for Alternative Menu Items

As discussed above, the presence of an XML file makes an alternative layout a menu item. The format of the XML file is the same as the format for core menu item XML files. With this XML file, you can add the parameters you wish to include for this menu item. They can be the same as one of the core menu items, or you can omit core parameters or add new ones. Note that if you add new parameters, these can be used in the layout file but will not be used in the core model or view files.

It is also possible to override parameter settings for core parameters. One example of this is to control which templates an alternative menu item layout can be displayed with. In some cases, you may want to allow a custom menu item to be displayed with any template for the site. In other cases, you may wish to limit that menu item's layout to one specific template. In this situation, you would just add the following parameter to the menu item's XML file:

<fields>
  <field
    name=''"template_style_id"''
    type=''"templatestyle"''
    label=''"COM_MENUS_ITEM_FIELD_TEMPLATE_LABEL"''
    description=''"COM_MENUS_ITEM_FIELD_TEMPLATE_DESC"''
    filter=''"int"''
    template=''"beez5"''
    class=''"inputbox"''>
  </field>
 </fields>

This will override the core template_style_id parameter. Setting the template equal to "beez5" in this case will limit the user to only selecting template styles for the "beez5" template.