wonder-slim element reference

Renders its content when the conditional just before it didn't: the "else" of an ERXWOConditional (<wo:if>). Written as <wo:else>.

<wo:if condition="$hasItems">…</wo:if>
<wo:else>No items</wo:else>

It must follow a conditional; used without one it throws.

The layout of the framework's error pages, for error pages of your own: a whole HTML page with a centered card, an icon, a heading, the content, and the application's name. ERXErrorPage, and the pages WebObjects shows when a session has expired, a page can't be restored or a session can't be created, are built on it.

<wo:ERXErrorLayout title="Not found" heading="That page doesn't exist">
	<p>The link may be old, or mistyped.</p>
	<p class="actions"><wo:link directActionName="default" class="button">Return to the front page</wo:link></p>
</wo:ERXErrorLayout>

It's self-contained (inline CSS and icon, no resources or scripts), so it renders even when what went wrong is the resources. Inside the content, class="muted" gives secondary text, class="actions" a paragraph of actions and class="button" a button.

Adds a script to the page: a <script> tag for a script resource (filename, optionally in a framework) or a URL (a filename that's a complete URL), rendered where the element is.

<wo:ERXJavaScript filename="app.js" defer />
<wo:ERXJavaScript filename="https://cdn.example/lib.js" integrity="sha384-…" crossorigin="anonymous" />

Every other attribute is rendered on the <script> tag. A bound type (such as module) replaces the default text/javascript. The element has no content: put inline script in a <script> tag.

Adds a stylesheet to the page: a <link> tag for a stylesheet resource (filename, optionally in a framework) or a URL (href). The tag goes before the page's </head>, or where the element is (see inline), and a stylesheet already added to the page isn't added again.

<wo:ERXStyleSheet filename="wonder-select.css" framework="AjaxSlim" />
<wo:ERXStyleSheet href="https://cdn.example/lib.css" integrity="sha384-…" crossorigin="anonymous" />

Every other attribute is rendered on the <link> tag. The element has no content: put inline CSS in a <style> tag.

Renders a <select> list (multiple choice with multiple), one option per item of list, and sets selections from the chosen options. Patch of WOBrowser, installed in its place, so it's what WOBrowser renders. Differences from WO's: list accepts any java.util.List or array (null renders no options), and anything else throws, where WO silently renders no options. selections receives a mutable array, and is always set: WO fails to set it, silently, when list is an immutable list such as List.of().

Every other attribute is rendered on the tag.

One case of an ERXWOSwitch: its content renders when the switch's value equals this case's case. Only valid as a direct child of ERXWOSwitch.

Renders a checkbox for each item of list, and sets selections from the checked ones. Patch of WOCheckBoxList, installed in its place, so it's what WOCheckBoxList renders. Differences from WO's: list accepts any java.util.List or array (null renders no options), and anything else throws, where WO silently renders no options. selections receives a mutable array, and is always set: WO fails to set it, silently, when list is an immutable list such as List.of().

Every other attribute is rendered on the tag.

Renders the content a component was given, like WOComponentContent, but can pick one named part of it. For wrapper components that take more than one piece of content: the parent passes named ERXWOTemplates, and each ERXWOComponentContent in the wrapper renders the one whose templateName matches.

<!-- in the wrapper -->
<header><wo:ERXWOComponentContent templateName="header">Default header</wo:ERXWOComponentContent></header>
<main><wo:ERXWOComponentContent /></main>

Without templateName it renders all of the given content except the ERXWOTemplates, so named parts aren't rendered twice. Its own content renders when the given content has no part with that name.

Embeds an already constructed component instance. Where <wo:MyComponent> (and WOSwitchComponent) construct the component themselves by name - leaving bindings as the only way to initialize it and giving you no handle to it - this element takes the instance from you: construct it (ERXComponentUtilities.instantiate(MyComponent.class, context())), configure it, keep a reference, call methods on it, and bind it to instance.

<wo:ERXWOComponentInstance instance="$inspector" selectedObject="$object">
  ...optional wrapped content, rendered by the instance's <wo:content />...
</wo:ERXWOComponentInstance>

Every other attribute is passed to the instance as a binding, exactly as on a normally embedded component. The instance is registered as a subcomponent of the page on first render, so it survives across requests (page cache, back button) like any embedded component. The binding is evaluated on every phase: bind a different instance and it is adopted immediately, the old one dropped from the page.

Rules, enforced with an exception: instance must not evaluate to null; the instance must not be stateless (stateless instances are pooled and shared); an instance already embedded in another parent is refused. Construct with ERXComponentUtilities.instantiate(), not pageWithName() - the latter awakens the instance and flags it as a page.

Renders its content when condition is true (negate flips it). Installed in place of WOConditional, so it's what <wo:if>, <wo:conditional> and WOConditional render. Unlike WO's, it records whether it rendered, so an ERXElse that follows it can render the alternative:

<wo:if condition="$hasItems">…</wo:if>
<wo:else>No items</wo:else>

Renders a <form>. Installed in place of WOForm, so it's what <wo:form> and WOForm render. Submits to its action, a direct action (directActionName/actionClass) or an href; without any of them, to the page's component action URL, where the submitted buttons decide the action. The method is post unless bound. As in WO's, a form inside another form is left out (browsers don't support nested forms), and an off-screen default submit button can be added (addDefaultSubmitButton), so pressing return submits. Differences from WO's:

- A nested form is left out with a logged warning, and not at all when it's embedded.
- Every form has a name, generated when name isn't bound (WO names only forms with a bound name), and publishes it to the context, for elements that need to refer to their form.
- disabled leaves the form's tags out, and fragmentIdentifier appends # + its value to the action.

Attributes prefixed with ? become query parameters. Every other attribute is rendered on the tag.

Renders an <input type="hidden"> and sets value from what's submitted. Patch of WOHiddenField, installed in its place, so it's what WOHiddenField renders. Differences from WO's: Adds a readonly binding: when true, the readonly attribute is rendered and the submitted value isn't taken.

Every other attribute is rendered on the tag.

Renders a link, <a>: to a URL (href), a component action (action), a page (pageName), or a direct action (directActionName/actionClass). Installed in place of WOHyperlink, so it's what <wo:link> and WOHyperlink render. Differences from WO's:

- A disabled link's action returns the current page, not an empty response.
- Actions of elements inside the link (such as an onclick element) are invoked.
- The invoked action is recorded for logging.
- With er.extensions.ERXHyperlink.defaultNoFollow, links with an action get rel="nofollow".

Attributes prefixed with ? become query parameters (?id="$item.id"). Every other attribute is rendered on the tag.

Renders an <img> tag for an image resource (filename, optionally in a framework) or a URL (src). Written as <wo:svg> for now. It's meant to become the one image element, for ng-objects as well.

<wo:svg filename="logo.svg" alt="Logo" />

Every other attribute is rendered on the tag (alt, width, height, loading, srcset, …). Unlike WOImage, it doesn't read the image to work out its dimensions: bind width/height if you want them.

Renders an <input type="password"> and sets value from what's submitted. Patch of WOPasswordField, installed in its place, so it's what WOPasswordField renders. Differences from WO's: Adds a readonly binding: when true, the readonly attribute is rendered and the submitted value isn't taken.

Every other attribute is rendered on the tag.

Renders a <select> with one option per item of list, and sets selection from the chosen option. Patch of WOPopUpButton, installed in its place, so it's what WOPopUpButton renders. Differences from WO's: list accepts any java.util.List or array (null renders no options), and anything else throws, where WO silently renders no options.

Every other attribute is rendered on the tag.

Renders its content once for every item of list, or count times. Installed in place of WORepetition, so it's what <wo:loop>, <wo:repetition> and WORepetition render.

<wo:loop list="$orders" item="$order" index="$i">…</wo:loop>
<wo:loop count="3" index="$i">…</wo:loop>

Unlike WO's, it also accepts object arrays (such as String[]), in addition to any java.util.List, and can put each item's hash code (or uniqueKey) in element IDs (checkHashCodes). An action then finds its own item even if the list changed between rendering the page and following the link, instead of acting on whatever item now sits at that position.

Renders a value as text, HTML-escaped by default, optionally formatted. Installed in place of WOString, so it's what <wo:str> and WOString render. Unlike WO's, it formats in the current locale (ERXLocale.current()), and formats java.time values, with dateformat or a DateTimeFormatter as formatter.

<wo:str value="$order.total" numberformat="#,##0.00" />
<wo:str value="$order.date" dateformat="%d.%m.%Y" />
<wo:str value="$order.shippedOn" dateformat="dd.MM.yyyy" valueWhenEmpty="Not shipped" />

At most one of dateformat, numberformat and formatter.

Renders the one ERXWOCase among its children whose case equals the value of case, a "multiple if".

<wo:ERXWOSwitch case="$status">
  <wo:ERXWOCase case="open">Open</wo:ERXWOCase>
  <wo:ERXWOCase case="closed">Closed</wo:ERXWOCase>
  <wo:ERXWOCase case="default">Unknown</wo:ERXWOCase>
</wo:ERXWOSwitch>

Its direct children must be ERXWOCase elements (whitespace between them is allowed). If no case matches, the case whose case is "default" renders, or nothing if there's none.

Renders the component (or dynamic element) named by WOComponentName, which can change from one render to the next. Installed in place of WOSwitchComponent. Unlike WO's, it identifies the chosen component in element IDs by a number instead of its name, which keeps component names out of URLs and makes them shorter.

Every other attribute is passed to the chosen component as a binding, and the content becomes its component content.

A named piece of content passed to a wrapper component, for wrappers that take more than one piece of content. Inside the wrapper, an ERXWOComponentContent with the same templateName renders it.

<wo:MyWrapper>
  <wo:ERXWOTemplate templateName="header">Title</wo:ERXWOTemplate>
  <wo:ERXWOTemplate templateName="body">…</wo:ERXWOTemplate>
</wo:MyWrapper>

A plain WOComponentContent in the wrapper renders all of the content, the templates included.

Renders an <textarea> and sets value from what's submitted. Patch of WOText, installed in its place, so it's what WOText renders. Differences from WO's: Adds a readonly binding: when true, the readonly attribute is rendered and the submitted value isn't taken.

Every other attribute is rendered on the tag.

Renders an <input> field and, when the form is submitted, parses its text back into value, optionally through a formatter. Installed in place of WOTextField.

<wo:WOTextField value="$price" numberformat="#,##0.00" />
<wo:WOTextField value="$email" type="email" blankIsNull="true" />

Numbers and dates are formatted and parsed in the current locale (ERXLocale.current()). With an Icelandic locale, for instance, 12.50 parses as 1250, so apps must only set a locale they mean. Every other attribute is rendered on the tag. At most one of dateformat, numberformat and formatter.

Content that can be collapsed and expanded with a clickable arrow and label. Each click is a component action that toggles visibility.

Carried over from JavaWOExtensions.

Renders an <iframe>. Its source is a URL (src), or a component action URL whose response is the page named by pageName, the element bound to value, or the element returned by the parent's binding named by actionName. The element's content renders inside the iframe tag, as fallback content.

Carried over from JavaWOExtensions.

Renders its content when the parent component's value for key equals value (compared with equals(); two nulls are equal). negate flips it.

Carried over from JavaWOExtensions.

Renders a <meta http-equiv="refresh"> tag that, after seconds, requests a component action URL. That action returns the page named by pageName, or the result of action.

Carried over from JavaWOExtensions.