这是Alan 一个系类中的一篇文章（2010年2月28），翻译成中文，方便自己方便后来的人。很多地方翻译的不是很好，还有很多地方需要后面优化。

原文地址

One of the more powerful parts of the Magento eCommerce System is the Admin’s System Config section. As a developer, it will allow you to quickly and easily setup forms elements that allow your end-users to configure their Magento System and your custom modules.

管理员系统设置 部分是Magento 系统最有权利的部分。作为一个开发者，在这个部分允许你快速方便地设置表单元素，以便终端使用着配置他们的Magento 系统模块和自定义的模块。

Like a lot of things in Magento, it can be intimidating the first time you attempt to setup a new configuration section from scratch, but once you’ve done it once the power of (nearly) code-less forms will become addictive. Let’s get started.

像Magento 里的其他事情一样，第一次尝试从头去配置一个新的设置部分会被吓到，但是你一旦掌握的了如何使用它你会喜欢上这些，开始吧。

We’ll be building off the module we created in the Magento Controller Dispatch and Hello World article, although any empty module should suffice. The impatient can download the complete module for this article here.

我们将在上面连接文章里的模块里创建，或者一个空白的模块也可以。如果不耐烦可以点击上面下载这篇文章的完整模块

The following is part of a longer series about Magento aimed at developers familiar with PHP MVC development. While each article can be read stand alone, each article does build on concepts and code covered in previous articles. If you’re confused, be sure to catch up on the older stuff first.

下面是一个关于 Magento 的长系列的一部分, 它针对的是熟悉 PHP MVC 开发的开发者。虽然每篇文章都可以单独阅读, 但每篇文章都是建立在以前文章所涵盖的概念和代码之上的。如果你感到困惑, 一定要先赶上旧的教程。

 

Adding A System Config File

The first thing we need to do is add a system configuration file to our module. This file is separate from config.xml, and can be found at the following location

第一件事我们要做的是，为我们的模块添加一个系统配置文件。这个文件是单独自 config.xml的，可以在一下路径里找到：

app/code/local/Alanstormdotcom/Helloworld/etc/system.xml

While similar to the global config, the system configuration information is stored separately. If you need to view the system config file, it exists as it’s own entity. You can view the entire system config by executing the following PHP code from any controller action

有些像 全局配置，系统配置信息是分别保存的。如果你要查看系统配置文件，它以自己的实体实例存在。（暂时完全不懂，后面再修改）。你可以查看整个系统的配置，用一下PHP代码从任何controller。【这里会返回一个很大的xml，包含了已安装的插件信息，包含core，可以搜索关键字 module= 】

//header('Content-Type: text/xml');            
header('Content-Type: text/plain');            
echo $config = Mage::getConfig()
->loadModulesConfiguration('system.xml')        
->getNode()
->asXML();            
exit;

The loadModulesConfiguration method will look in each configured module’s etc folder for a file with the passed in name (in this case, system.xml). Magento has a number of other configuration files (api.xml, wsdl.xml, wsdl2.xml, convert.xml, compilation.xml, install.xml), and as a module developer you can leverage this functionality to create your own.

loadModulesConfiguration方法将会查询在每一个已经配置的模块的etc文件下，传入的名字的文件（在本例子中，为system.xml）。Magento有很多的其他配置文件比如api.xml,wsdl.xml.wsdl2.xml,convert.xml,compliation.xml,install.xml。作为一个开发者，可以利用这些功能去创建自己的 配置文件 。

 

Adding a new Tab

The first thing we’re going to do is a add a custom “Tab” to the System Configuration. Tabs are the navigation headers down the left hand side of the Admin in System->Configuration. The default tabs are General, Catalog, Customers, Sales, Services, and Advanced.

第一件事，我们要做的是添加一个Tab在系统设置里。Tabs是在后台管理页面导航栏头部system–> configuration 下进入，左边栏的那一部分。默认的Tabs有这些：General, Catalog, Customers, Sales, Services, and Advanced 等

Let’s create a new one named “Hello Config”. Create a new system config file and add the following

Location: app/code/local/Alanstormdotcom/Helloworld/etc/system.xml
<config>
    <tabs>
        <helloconfig translate="label" module="helloworld">
            <label>Hello Config</label>
            <sort_order>99999</sort_order>
        </helloconfig>
    </tabs>    
</config>

首先创建一个‘Hello Config’的模块，创建一个新的系统配置文件【system.xml】并写入代码。

A few explanations are in order. The name of the <helloconfig /> node is arbitrary, but should be unique among Tabs. It will serve as an identifier for your tab which we’ll use later in the config.

按数序介绍：<helloconfig />代码段是任意定义的但是要唯一。这个用作你 稍后配置的的tab的一个标识符。

The module="helloworld" attribute identifies which module this tab “belongs” to, <label> determines the name that will be used for your tab, and <sort_order> determines where the tab shows up in relation to the other tabs in the left hand navigation.

module="helloworld" 这个属性用来标识这个tab属于那个模块。<label>决定了用作tab的名字。<sort_order>决定了这个tab在左侧导航的排序。

With this in place, head over to the System -> Config section. One of two things should happen

操作了这些之后，回到 System -> Config部分，有两件事可以发现：

1. The page will load as expected, but without your new tab
2. You’ll get an error something like the following:
   Fatal error: Class 'Mage_Helloworld_Helper_Data' not found in

1.网页可以正常刷新显示，但是没有我们的新tab

2.会得到错误提示 ‘Mage_Helloworld_Helper_Date’

A Brief Interlude(插曲) for Helper Classes

Like a lot of popular PHP MVC systems, Magento has Helper classes, which are used for a variety of tasks that don’t fit neatly into Model, View, or Controller. Helper classes are one of the abstracted grouped class names, meaning system users can override default classes and module developers need to add a section to their config.xml to specify the base class name for Helpers.

如同其他PHP的MVC系统一样，Magento拥有Helper类，用于不适合在Model,View或Controller中合适贴合的各种任务。Helper类是grouped class names的一个实例化。意味着系统使用者可以覆写默认的classes，模块开发者需要在 config.xml 文件中添加一个段落用来给Helpers致命基本的类名。

A lot of the Magento System code assumes a module has a default Helper class. If you got the exception mentioned above, it’s because your Helloworld module didn’t have this default Helper class and the System was trying to use it. Let’s add one now.

Magento系统假定一个模块是有默认的Helper类。如果你看到了上面提到的错误，这是因为Hello World 模块没有一个默认的Helper类而系统又尝试去使用它，现在我们自己添加一个。

First, we need to add a section the to module’s main config.xml file (NOT the system config)

首先我们在 config.xml（注意不是system.xml文件）添加模块的主配置段落。

File: app/code/local/Alanstormdotcom/Helloworld/etc/config.xml

<!-- ... -->
<global>
    <!-- ... -->
    <helpers>
        <helloworld>
            <class>Alanstormdotcom_Helloworld_Helper</class>
        </helloworld>
    </helpers>    
    <!-- ... -->
</global>
<!-- ... -->    

If you’ve spent anytime in the Magento config this should be straight forward. The <helloworld /> tag should be named after your module, and the <class /> tag should contain the base name of all your Helper classes, named with the Magento standard convention

如果已经有配置Magento 的经验，可以直接跳过此段落。【算了还是继续看吧】<helloworld /> 应当在模块后命名，<class />应当包含Helper 类基本的名字，以Magento 的标准约定方式命名：

Packagename_Modulename_Helper

Helper’s are loaded with the global Mage object’s static helper method. The following call (assuming the above config file)

Helper 类加载的是全局变量Mage 对象的静态 helper方法。以下调用（假定以下配置文件）

Mage::helper('helloworld/foo');

将会调用

app/code/local/Alanstormdotcom/Helloworld/Helper/Foo.php
class Alanstormdotcom_Helloworld_Helper_Foo

Magento also has the concept of a default Helper for a module. If you provide the Helper class with only the module name

Magento默认模块有一个默认的Helper类，如果你提供的Helper类只有模块名字：

Mage::helper('helloworld');

it will look for a data Helper located at

app/code/local/Alanstormdotcom/Helloworld/Helper/Data.php
class Alanstormdotcom_Helloworld_Helper_Data ...

That means the following two calls are equivalent.

这意味着以下两个调用是等价的：

Mage::helper('helloworld');
Mage::helper('helloworld/data');

Finally, we need to add the actual Helper class. Add the following file, and you’ll be good to go.

最后，我们需要添加的当前的Helper类，添加一下代码到文件：

File: app/code/local/Alanstormdotcom/Helloworld/Helper/Data.php
class Alanstormdotcom_Helloworld_Helper_Data extends Mage_Core_Helper_Abstract
{
}   

With all this done, clear your Magento cache and reload the System admin. Your error message should be gone, but your new tab is still missing.

操作完以上后，清空缓存并刷新页面，错误信息会消失，但是tab还是空的。

Note: If you’re curious about the kind of things a helper can do for you, checkout the Mage_Core_Helper_Abstract class for a list of useful methods that all helpers will have.

备注：如果你有兴趣了解各种helper可以做的事情，你可以检查Mage_Core_Helper_Abstract类去找出所有helper有的有用的方法。

Adding A New Section

The Helper interlude out of the way, our next step is figuring out why our configured Tab isn’t showing up. Each Tab has a number of sections. For example, the Advanced tab has (by default) an Admin, System, Advanced, and Developer section.

Helper类的事情讲完了，我们下一步解决为什么配置的tab没有显示。每一个tab都有几个小分类，比如默认的Advanced有Admin, System, Advanced, and Developer等小分类。

If a Tab is configured with no sections, it won’t show up. Let’s fix this by adding a <section /> node to our system config

如果Tab设置成没有小分类，它不会显示，添加<section /> 标签在system.xml中来修复此问题：

Location: app/code/local/Alanstormdotcom/Helloworld/etc/system.xml
<config>
    <tabs>
        <helloconfig translate="label" module="helloworld">
            <label>Hello Config</label>
            <sort_order>99999</sort_order>
        </helloconfig>
    </tabs>    
    <sections>
        <helloworld_options translate="label" module="helloworld">
            <label>Hello World Config Options</label>
            <tab>helloconfig</tab>
            <frontend_type>text</frontend_type>
            <sort_order>1000</sort_order>
            <show_in_default>1</show_in_default>
            <show_in_website>1</show_in_website>
            <show_in_store>1</show_in_store>                    
        </helloworld_options>
    </sections>        
</config>

There’s some familiar nodes in this new configuration section, as well as a few new faces.

这里有些熟悉的标签这新的配置代码段落，当然也有新面孔。

What is a <helloworld_options/>?

Similar to the <helloconfig /> tag above, this in a arbitrary name that’s used to identify your new section.

和<helloconfig />标签一样，这是一个任意定义的名字用来标识新的小分类。

What is a <label />?

A label defines the display value used in the HTML interface for your new section.

标签用来定义显示在HTML界面的名称。

What is a <tab />?

This identifies which Tab your new section should be grouped under. We want our section to show up under our new helloconfig Tab. The helloconfig name comes from the tag used to create the Tab (<helloconfig/>)

这个标识符新的小分类分组在那个Tab下面，我们希望小分类展示在新的Hello Config Tab,这个helloconfig 名字来自与我们创建的Tab (<helloconfig/>)

What is a <frontend_type />?

This one it tricky. <frontend_type /> has meaning in other sections of the configuration (see below), but it doesn’t appear to do anything here. However, sections in the Core modules use this tag, so it’s best to follow the convention, even when you’re not sure what it does.

这一个有点难回答。<frontend_type/> 在配置的其他部分中有意义 (见下文), 但它在这里似乎不起任何作用。但是, 核心模块中的节使用此标记, 因此最好遵循该Magento 约定, 即使您不确定它的用途。

What is a <sort_order />?

Again, <sort_order /> determines where this sections shows up vertically（垂直） compared to other sections in the Tab.

有一次<sort_order /> 决定了这个小分类与其他小分类在这个tab里的垂直顺序。

What is a <show_in_default />, <show_in_website />, <show_in_store />?

These are boolean config options, with a valid value of 1 or 0. They determine the level of configuration score/granularity（分数/粒度） this section has.

这些是一些布尔值类型的配置选项，可以值只有1或0.这些设置决定此部分的配置xi范围级别。

With our section configured, Let’s head over to System -> Config again (reloading the Admin page often won’t be enough). You should now see your section and tab near the bottom of the left hand navigation. You can add more sections by adding additional nodes to the <sections /> node.

带着我们的此段小分类的配置，再次回到System -> Config （刷新这个admin的页面通常是不行的，可能要推出登录）。你将会看到小分类和Tab出现在左侧导航区块的下方。你可以通过配置<sections />代码添加更多的小分类。

 

Access Control 访问控制

If you click your new section link you’ll be disappointed by the results. A blank admin page will load, and the entire left hand navigation will vanish（烟消云散）. That’s because the Adminhtml application can’t find an entry for our new section in the Access Control List (ACL).

如果你点击了你新的小分类，看到结果后你会失望。你个空白的页面将会出现，整个左边的导航区块会消失。这是因为Adminhtml应用程序在ACL（访问控制列表）找不到我们新的小分类的入口。

ACL is a topic all its own, but I’ll try to explain enough here so this doesn’t seem like total magic. This section is optional, and if you’re not interested skip to the end for the magic XML to paste into your config.xml

ACL是一个主题，但是作者准备详尽的解释它，以至于它不会看起来完全就是一个魔术。这个章节是可选阅读的，如果没有兴趣，可以跳转到最后把充满魔术的XML贴到config.xml 里去（那样子就失去作者和翻译的意义了）

There are certain（某些） resources (where resource is a loosely defined term（学术；长期）) that require a user to be authenticated before using them. Resource here is an abstracted（抽象） term. It might be a page in the admin, or it might be access to a certain feature. The Magento team decided that System Config sections should have ACL protection.

有些资源（那些被术语松散定义的）需要用户在使用前被授权。资源在这里是一个抽象概念，可以是admin里第一个page或者是可以进入某些功能的权利。Magento team 决定系统设置章节需要一个ACL保障。

Resources are defined via URI’s. For example, the “web” config section (under the General tab), if defined with a URI of

admin/system/config/web

资源可以用URI来定义，比如系统自带的web设置小分类（在 General tab下），如果一个资源被以下URI定义：

Our helloworld_options section would have a URI of

admin/system/config/helloworld_options

那我们的小分类 helloworld_options 应该用URI这样定义

The Admin application (often called Adminhtml) is built using the same framework as the store application (the store application is often called the frontend application). In Adminhtml action controllers, whenever a user needs to access a resource protected by ACL, the Adminhtml developer must

Admin应用程序（一般叫做Adminhtml）是和store应用程序（通常叫做 frontend 应用程序）一样的框架架构。在Adminhtml的操作控制器中，每当用户需要去访问ACL保护的资源时，Adminhtml需要以下操作：

1. Derive a URI for whatever resource the end-user is trying to access
2. Check that URI against the ACL system, which will determine if the
   logged in user has the right privileges that particular resource
3. If the user does have the correct privileges, proceed. If they don’t, boot them
   or do something appropriate (like stop rendering the navigation and content areas)

1.为准备访问资源的终端用户分配一个RUI.

2.检查URI和ACL是否匹配，这将决定了登录的用户是对特定的资源有正确的权限。

3.如果用户有正确的权限，继续处理。如果没有，引导他们或者做一个正确的事情（比如停止加载导航和内容区块）

For those interested, this is done for the System Config sections in the _isSectionAllowedmethod in the following controller

app/code/core/Mage/Adminhtml/controllers/System/ConfigController.php

如果想了解更多，在下面列出的控制器中，_isSectionAllowed 这个方法是为系统设置章节完成的。（翻译的不是特别好）

If you go to System -> Permissions -> Roles, add click the Add a new role button, you can see a graphical tree representation of all the Role Resources defined in your Magento install.

如果你在后台的 系统–>权限和角色–>角色 中，点击新增一个角色，你可以看到一个树形图形表示所有在Magento 已经安装的 角色资源。

 

Adding an ACL role （添加一个访问控制列表的角色）

That out of the way, we need to define an ACL resource for our new section. You only need to do this if you’re adding a new section. If you’re adding config options to an existing section you don’t need to touch ACL.

.叉开一个话题，我们需要为我们的新章节（小分类）定一个一个ACL资源。你只需要做这些当你在添加一个新的的章节时。如果你为一个已经存在的章节添加控制选项，你不需要接触到ACL.

In your module’s config.xml, add the following section

在你的模块的 config.xml文件，添加一下代码

File: app/code/local/Alanstormdotcom/Helloworld/etc/config.xml    
<config>    
    <!-- ... -->
    <adminhtml>
        <acl>
            <resources>
                <admin>
                    <children>
                        <system>
                            <children>
                                <config>
                                    <children>
                                        <helloworld_options>
                                            <title>Store Hello World Module Section</title>
                                        </helloworld_options>
                                    </children>
                                </config>
                            </children>
                        </system>
                    </children>
                </admin>
            </resources>
        </acl>
    </adminhtml>
    <!-- ... -->
</config>

Yes, that’s a mouthful. Let’s break it down a bit. First off, all defined resources are contained in the following node structure.

是的，这是一大段代码，让我我们分解理解它。第一，我们定义的资源包含以下节点代码结构：

<adminhtml>
    <acl>
        <resources>
        </resources>
    </acl>
</adminhtml>

Within resource, each descending node represents a URI portion. So, this far down

在资源内部，每个降序节点代码代表一个URI 部分，所以一下的代码

<admin>
    <children>
        <system>
            <children>

gives us a URI of

给出了URI的一部分

admin/system

If you follow that all the way down, you get to the node for our config

如果继续往下看完所有，你可以看到我们设置的节点代码：

<helloworld_options>
    <title>Store Hello World Module Section</title>
</helloworld_options>

Title is what will show up in the Permissions admin.

title是现在后台 权限和角色设置下的名字。

With this in your config and your Magento cache cleared, you should now be able to view your config section. You may need to log out of the application and back into to see it. The Admin has some additional caching beyond the standard Magento cache that I haven’t been able to track down. If(typo) you log out, log back in, and navigate to your section you should now see a blank config page titled “Hello World Config Options”.

操作完上面的射中后并且清空Magento 缓存，你会看到你的设置的 小分类，你需要登出登录Magento 才能看到效果。因为Admin会有一些附加的缓存，超越了Magento 缓存里，作者找不到他们。如果你登出在登入，导航部分的你的小分类将会展示一个有着‘Hello World Config Options’标题的空白设置页面。

 

Adding Groups （添加分组）

So, we now have a blank config section. Our next step is adding a group.

到此，我们已经有了一个空白的设置小分类。我们的下一步是添加一个分组（就是点击小分类后，右侧栏位显示的不同设置的可以点击折叠或展开的，分组显示）

Groups are used to group together different configuration options, and are displayed in the Magento admin with a pop-open widget. For example, in a stock install the Advanced section has a single group named “Disable modules output”. Let’s create a group named “messages” by adding a <groups /> node to our config, nested within the <sections> node.

分组是用来分组聚集不用的配置选项，用来展示Magento 管理后台（admin不知道翻译的对不对）弹出展示的部件。举个例子，在后台设置 Advanced 章节只有有一个单独的分组叫做 ‘Disable modules output’（禁止模块输出）【用来控制插件的disabled或者enbale】，

让我们一起创建一个叫‘messages’的分组，用在config里添加一个<groups /> 的节点代码，把它嵌入<sections>的节点代码中（system.xml）。

Location: app/code/local/Alanstormdotcom/Helloworld/etc/system.xml
<config>
    <tabs>
        <helloconfig translate="label" module="helloworld">
            <label>Hello Config</label>
            <sort_order>99999</sort_order>
        </helloconfig>
    </tabs>    
    <sections>
        <helloworld_options translate="label" module="helloworld">
            <label>Hello World Config Options</label>
            <tab>helloconfig</tab>
            <frontend_type>text</frontend_type>
            <sort_order>1000</sort_order>
            <show_in_default>1</show_in_default>
            <show_in_website>1</show_in_website>
            <show_in_store>1</show_in_store>
            <groups>
                <messages translate="label">
                    <label>Demo Of Config Fields</label>
                    <frontend_type>text</frontend_type>
                    <sort_order>1</sort_order>
                    <show_in_default>1</show_in_default>
                    <show_in_website>1</show_in_website>
                    <show_in_store>1</show_in_store>                
                </messages>
            </groups>
        </helloworld_options>
    </sections>        
</config>

Each tag within this node is analogous（类似） to the tags from the top level <section /> node.

If you reload your page, you’ll now see an empty pop-open box with the title “Demo Of Config Fields”.

此节点代码每一个标记都类似于顶层<section /> 节点代码的标记。

如果你刷新你的设置页面，你将会看到一个空的弹出显示的窗口，标题是‘Demo Of Config Fields’

Adding Config Fields （设置项）

Finally, we need to add our individual configuration fields. You’ll do this by adding a <fields /> node to your <messages /> node. We’ll start with a field name “hello_message”.

最后我们需要为添加单个的设置项，需要添加一个<fields />到<messages /> 代码段。我们把hello_message最为设置项的名字。

<!-- ... -->
<messages translate="label">
    <label>Demo Of Config Fields</label>
    <frontend_type>text</frontend_type>
    <sort_order>1</sort_order>
    <show_in_default>1</show_in_default>
    <show_in_website>1</show_in_website>
    <show_in_store>1</show_in_store>                
    <fields>
        <hello_message>
            <label>Message</label>
            <frontend_type>text</frontend_type>
            <sort_order>1</sort_order>
            <show_in_default>1</show_in_default>
            <show_in_website>1</show_in_website>
            <show_in_store>1</show_in_store>                    
        </hello_message>
    </fields>                    
</messages>
<!-- ... -->    

Again, fields within your new <hello_message> node are analogous to the other nodes you’ve added so far. However, this time <frontend_type>text</frontend_type> actually does something useful by letting the system know what kind of form element you want. Reload your page, and you should now see an individual text field in the popup box.

同样的，我们新的<hello_message>代码段和其他已经添加的代码段是类似的。然而，这次的<frontend_type>text</frontend_type>实际上起到了一些作用：告诉system我们需要什么样的表格元素。刷新载入页面，我们可以看到一个新的文本设置醒在弹出的页面【应该就是鼠标点击之后看到】

Once all this configuration information is in place, you’re done. No code is needed to save/load/update your config value. The system handles that all for you.

一旦这些设置信息准备就绪了，我们也就成功了。不要代码来保存/上传/更新我们的配置设定值。system会帮我们处理。

You’re not limited to text fields. Let’s add a field called <hello_time/>

我们不限于文本选项，让我添加一个选项叫做 <hello_time/>【还是在system.xml里】

<!-- ...-->
<fields>
    <hello_message>
        <label>Message</label>
        <frontend_type>text</frontend_type>
        <sort_order>1</sort_order>
        <show_in_default>1</show_in_default>
        <show_in_website>1</show_in_website>
        <show_in_store>1</show_in_store>                    
    </hello_message>
    <hello_time>
        <label>Time to Say Hello</label>
        <frontend_type>time</frontend_type>
        <sort_order>1</sort_order>
        <show_in_default>1</show_in_default>
        <show_in_website>1</show_in_website>
        <show_in_store>1</show_in_store>                    
    </hello_time>        
</fields>
<!-- ... -->

Notice that the main difference here is the

<frontend_type>time</frontend_type>

留意此处有一个不同的地方【frontend_tyoe】标签

Reload your page, and you’ve now got a config field for saving a time value.

刷新页面，这时候我们有了ige保存时间数值的选项。

Many, but not all, of the built in Varien data form classes (lib/Varien/Data/Form/Element) are supported. The <frontend_type /> tag acts as an identifier for a factory-ish pattern. Let’s try changing our hello message to a select field.

经常，但不是每一次，被来自(lib/Varien/Data/Form/Element)的Varien data的类是支持的【没看懂，先直译】，这些<frontend_type />的标签实际是一个工厂模式的标识符。让我尝试修改我们的 hello message变成一个select设置选项。

<!-- ... -->
<hello_message>
    <label>Message</label>
    <frontend_type>select</frontend_type>
    <sort_order>1</sort_order>
    <show_in_default>1</show_in_default>
    <show_in_website>1</show_in_website>
    <show_in_store>1</show_in_store>                    
</hello_message>
<!-- ... -->

If you reload your page you’ll see that you have an HTML select, but without any values. We’re going to need to add a source model to our field definition. Try this instead.

如果你刷新页面，你将可以看到一个html选择器，但是没有任何选项值。我们现在为选项定义【没翻译好】增加一个资源模型。尝试用一下代替上面代码

<hello_message>
    <label>Message</label>
    <frontend_type>select</frontend_type>
    <!-- adding a source model -->
    <source_model>helloworld/words</source_model> 
                           
    <sort_order>1</sort_order>
    <show_in_default>1</show_in_default>
    <show_in_website>1</show_in_website>
    <show_in_store>1</show_in_store>                    
</hello_message>    

The <source_model> element defines a URI for a Model class that we’ll use to provide default values for the select. This means we’ll need to make sure that our module config.xml has its models section setup

<source_model>元素定义了一个Model类的URI,那些我们用来给selec提供一个默认值。这一位置，我们要保证，我们的模型有一个models片段在config.xml

File: app/code/local/Alanstormdotcom/Helloworld/etc/config.xml
<config>    
    <!-- ... -->
    <global>
    <!-- ... -->
        <models>
            <!-- ... -->
            <helloworld>
                <class>Alanstormdotcom_Helloworld_Model</class>
            </helloworld>    
            <!-- ... -->
        </models>
    </global>
</config>

See the Magento Models and ORM Basics and the Class Instantiation Abstraction and Autoload article if you’re not sure what’s going on in that config.

有两篇帮助文章，用来搞懂config文件的作用

So, with that in place, if we reload our page after a cache clearing, we’ll end up with an Error something like

做到这一步，清空缓存重新加载页面，会看到下面这种的错误提示：

Warning: include(Alanstormdotcom/Helloworld/Model/Words.php)

That’s because we haven’t defined our source Model class. Let’s do that now.

这是因为我们还没有定义资源Model的类，让我们来添加它：

Note: If the warning you’re getting uses a Mage/Helloworld/... path, that means you haven’t setup your <model /> section correctly in config.xml.

注意：如果错误提示是Mage/Helloworld/... 的路径，这说明你还没有在config.xml里正确地配置<model />

To define our source Model, add the following file

为了定义我的资源Model，添加一下文件：

File: app/code/local/Alanstormdotcom/Helloworld/Model/Words.php
class Alanstormdotcom_Helloworld_Model_Words
{
    public function toOptionArray()
    {
        return array(
            array('value'=>1, 'label'=>Mage::helper('helloworld')->__('Hello')),
            array('value'=>2, 'label'=>Mage::helper('helloworld')->__('Goodbye')),
            array('value'=>3, 'label'=>Mage::helper('helloworld')->__('Yes')),            
            array('value'=>4, 'label'=>Mage::helper('helloworld')->__('No')),                        
        );
    }

}

Source Models are classes that respond to a method named toOptionsArray. This method should return an array of values that are used to populate the default values of our form elements (which descend from the Varien_Data_Form_Element_Abstract hierarchy). For a select element, this means defining a set of value/label pairs. In the above example, we’re passing our labels through the Helper’s translation method (__). While not necessary, this is always a good practice. You never know when you’re going to get big in Japan!

资源Model使用来回应叫做toOptionsArray这个方法的类。此方法是用来返回数组的值，哪些我们用来填充表格元素的默认值（继承于Varien_Data_Form_Element_Abstract 结构）。对一个select元素而言，这以为只定义了一对值/标签。在上面的例子中，我们传递我们的标签通过Helper的翻译方法  (__) 。虽然不是必要的，但仍然是一个好的经验。这句话不翻译了，没有实际意义。

Reload your page, and you should have a working select field.

刷新页面，我们可以看到select字段可以正常工作了。

For those interested in the Magento internals, the initFields method in the following class is where the source Model is used to set the field’s value

app/code/core/Mage/Adminhtml/Block/System/Config/Form.php

对此感兴趣的可以在下面文件可以了解Magento内部代码，initFields这个方法是我们资源Model用来设定字段值【待改进】。

Adding to Existing Config Sections/Groups（添加到已经存在的分类和分组）

In addition to setting up your own config Tabs and sections, you can add to an existing System Config section by adding appropriate sections to your own system.xml file.

除了设置我们自己的Tabs和小分类，我们还可以添加一个已经旬在的System Config的章节里去，做法是在system.xml里添加合适的代码段。

For example, if you add the following

File: app/code/local/Alanstormdotcom/Helloworld/etc/system.xml
<config>
    <!-- ... -->
    <sections>
        <!-- ... -->
        <general>
            <groups>
                <example>
                    <label>Example of Adding a Group</label>
                    <frontend_type>text</frontend_type>
                    <sort_order>1</sort_order>
                    <show_in_default>1</show_in_default>
                    <show_in_website>1</show_in_website>
                    <show_in_store>1</show_in_store>                    
                </example>
            </groups>
        </general>
        <!-- ... -->
    </section>
</config>

you’ll have a new group in the general Tab called “Example of Adding a Group”.

你讲会得到一个新的group的叫做Example of Adding a Group，在普通的Tab里。

Retrieving Values（检索值）

We’ve covered how to setup forms for creating configuration values. To retrieve values in our client applications and modules, we’ll use the getStoreConfig method on the global Mage object. For example, to grab the value of the select we created above, we’d use

我们已经了解如何去设置一个表格彬彬个创建设置的值。为了在客户程序和模块里索引值，我们将会全局Mage 对象在使用getStoreConfig 返回广发。例如，为了抓去我们上面创建select的值，我们应当如此操作：

Mage::getStoreConfig('helloworld_options/messages/hello_message');

The getStoreConfig method accepts a single parameter that’s a URI in the following format

getStoreConfig 发发接受一个单个的参数，所以URI会这样的格式

section_name/group_name/field_name

You can also grab an array of all your config values by specifying a partial path

你也可以用特定的部分路径去扎un去我们设置值的数组形式

Mage::getStoreConfig('helloworld_options/messages');
Mage::getStoreConfig('helloworld_options');

Finally, if you need to grab a value for a store that isn’t the store being used by the current session, getStoreConfig accepts a second parameter, the store ID

最后，如果抓取的store的值不是希望的，可以在getStoreConfig 添加第二个参数，store ID

Mage::getStoreConfig('helloworld_options',1);

Wrapup（提要）

We started off wanting to setup some System Config sections, and ended up exploring Helper classes, Access Control Lists, and the Varian Form hierarchy. In addition to what we covered above, it’s possible to create System Config options that use custom frontend and backend Models, which I’ll try to cover in a latter article.

我们从想在System Config添加一个Tba开始，讲到了 Helper 的类，访问控制列表ACL 和Varian的表格层次结构。此外我们上面所包括的，如何在System Config 选项里使用我们自定义的前台和后台的Modles，我们将在下一篇文章讲到。

You can download the complete module for this article here.