Apply (Recommended)

We suggest using [](http://books.zkoss.org/zk-mvvm-book/8.0/shadow_elements/shadow_elements.html) instead of `Include`. Because comparing to `Include`, it has several advantages:

  1. Doesn’t consume extra memory.

    Because it’s a shadow element, it doesn’t create a corresponding component at the server side.

  2. Doesn’t render an extra <div> surrounding its child components at the client-side.

    Include renders a <div> to enclose its child components. Sometimes the outer <div> breaks the layout.

  3. Doesn’t create an ID space.

    Include itself is an ID space owner which affects you when locating a component with ZK selector syntax.

  4. It can render its child components upon parameters dynamically.

    You can pass a parameter with data binding and bind to the parameter. When the parameter’s value changes, the content will change accordingly.

Include

Include allows you to include a zul page, an HTML, zhtml, JSP page, or a URL mapped to a servlet. For example,

<include src="another.zul"/>
<include src="another.jsp"/>

When including a ZUML page, the components specified in the ZUML page will become the child components of the org.zkoss.zul.Include component.

For example, suppose we have two ZUL pages as follows:

<!-- first.zul -->
<include src="second.zul"/>

and

<!-- second.zul -->
<listbox>
    <listitem label="foo"/>
</listbox>

Then, listbox in second.zul will become the child of include in first.zul.

When including a non-ZUML page (such as JSP), the output of the page will be the content of the org.zkoss.zul.Include component. Thus, the output must be a valid HTML fragment without `

, , `. If you prefer to create an independent page ([org.zkoss.zk.ui.Page](https://www.zkoss.org/javadoc/latest/zk/org/zkoss/zk/ui/Page.html)), or want to include a page rendered by `Richlet` while the value of src ends with `.zul` or `.zhtml`, you could specify the mode with `defer` ([org.zkoss.zul.Include#setMode(java.lang.String)](https://www.zkoss.org/javadoc/latest/zk/org/zkoss/zul/Include.html#setMode(java.lang.String))). Then, `include` won't have any child. Rather, an instance of [org.zkoss.zk.ui.Page](https://www.zkoss.org/javadoc/latest/zk/org/zkoss/zk/ui/Page.html) will be created to hold the content of `second.zul` or the content generated by Richlet. For more information, please refer to [ZK Component Reference: include](/zk_component_ref/include). # Classpath Web Resource Path ZK provides a special path URL starting with **`~./`**, it looks for a file under a folder starting with **`web`** in a web application's classpath, e.g. - `my-module.jar/web/`. - WEB-INF/classes/web So it will get a file under the path among all included jars. You can specify such URL in a component path-related attribute like: ```xml apply templateURI: component directive: image src: ``` ## Modular Resource Sharing The `~./` path simplifies sharing resources across projects. For example, when creating a sub-module project, you can store reusable assets such as CSS files, images, JavaScript, or ZUL templates in this path. By packaging the sub-module as a JAR and including it in your main project, the main project can easily access these resources using the `~./` path. This approach makes it convenient to manage and reuse static resources without duplicating files across projects. However, since files under the `~./` path are publicly accessible, avoid placing sensitive or confidential data in these folders. # Application-wide Named If you prefer an application-wide named [](http://books.zkoss.org/zk-mvvm-book/8.0/syntax/apply.html) element with a predefined templateURI and default parameters, you could specify it in [a language addon](/zk_client_side_ref/language_definition). For example, we could prepare a file called `WEB-INF/lang-addon.xml` with the following content: ```xml myapp xul/html mytemplatecomp ~./template/mytemplate.zul ``` Next, we could specify this file by adding the following content to `WEB-INF/zk.xml`: ```xml /WEB-INF/lang-addon.xml ``` Then, we can use it with a custom tag name: ```xml ``` For more information, please refer to [ZK Configuration Reference](/zk_config_ref/the_language_config_element).