Icons

This sections describes how to work with icons in Plone 6 Classic UI. Examples include the following.

• Bootstrap icons

• SVG inline icons

• Iconresolver

Bootstrap Icons

Twitter Bootstrap 5 is the default CSS framework in Plone 6. Plone uses its icons. Check out all the available Bootstrap icons at icons.getbootstrap.com.

Icons are shipped via plone.staticresources. See the file package.json of the package to get the actual version of the icons in Plone.

Registration

Icons are registered in Plone's registry. This provides an option to customize the content type and Plone UI icons by overriding icons via XML. Plone ships with the following icon registrations by default.

• Bootstrap

• Content Type

• MIME type

• Language Flags

• Country Flags

• Plone

• Toolbar

The icons above are made available as Plone resources. For example, the icon registered as lightning has the resource path of ++plone++bootstrap-icons/lightning.svg. In XML, with its prefix, its full name is plone.icon.lighting. One could register another icon set under a new name, for example ++plone++fontawesome-icons, and override the registrations above to use them.

Contextual Icons

Plone defines contextual icons which are used in specific places in a website. For example, we have an icon registered under the name plone.icon.plone-copy in https://github.com/plone/plone.staticresources/blob/master/src/plone/staticresources/profiles/default/registry/icons_plone.xml. It points to the bootstrap clipboard-plus icon ++plone++bootstrap-icons/clipboard-plus.svg. To use a different icon than the system default, you can override the registration for plone.icon.plone-copy with another icon path.

Icon expression

• The field icon_expr is used again to define icons for actions, content types, and other purposes.

• Use the icon name for icon expressions.

Example:

<property name="icon_expr">string:list-check</property>

Icon resolver

The icon resolver takes an icon's name without the plone.icon. prefix, such as plone-copy or align-center, and resolves it to the URL of an actual icon.

http://localhost:8080/Plone/@@iconresolver/plone-copy
http://localhost:8080/Plone/@@iconresolver/align-center

The icon resolver can be used to get an icon's URL or an inline icon (or tag) via a Python expression as shown in the sections Get an icon's URL via Python expression and Get an inline icon (tag) via Python expression.

Get an icon's URL via Python expression

The url method of the @@iconresolver view returns the actual URL to the SVG icon. The icon resolver view is globally available in templates under the name icons. This can be used in a template for an img tag:

<img class="custom-class"
    alt="foo"
    src="${python:icons.url('alarm')}" />

Get an inline icon (tag) via Python expression

The tag method is used with tal:replace. It returns an SVG image. Inline icons can be styled via CSS. tag_class and tag_alt are used to pass in custom classes and an alt text.

<tal:icon
  tal:replace="structure python:icons.tag('alarm')" />

<tal:icon
  tal:replace="structure python:icons.tag('archive', tag_class='custom-class', tag_alt='foobar')" />

Get inline icon (tag) in a template via traversal

<tal:icon tal:replace="structure icons/alarm" />

Get an inline icon (tag) in JavaScript

const baseUrl = $("body").attr("data-portal-url");
let icon = null;
if(baseUrl){
    const url = baseUrl + "/@@iconresolver";
    if (url) {
        const resp = await fetch(`${url}/${name}`);
        icon = await resp.text();
    }
}

Mockup provides an iconResolver function, defined in core/utils.js This function resolves icons the same way. It also has a fallback for demo and testing.

Fallback

There is a Plone icon defined as fallback if the name of the icon cannot be found in the registry.

Fallbacks are grouped, such as mimetype icons.

For example, the JPEG icon is in this group, as well as the mimetype group, and is named mimetype-image/jpeg. You can also register specific image icons. If there is no specific icon in that group, then mimetype-image is used as the fallback.