headliner:headline

For a record object: {record} in fluid_styled_content, {data} in a Content Block, a card of a collection.

Give it the record and it does the rest. The text comes from the label field of the record's table, so the record is written once:

<html xmlns:f="http://typo3.org/ns/TYPO3/CMS/Fluid/ViewHelpers"
      xmlns:headliner="http://typo3.org/ns/Twtgroup/Headliner/ViewHelpers"
      data-namespace-typo3-fluid="true">

<headliner:headline record="{record}" />
<headliner:headline record="{record}" subheader="1" />

<f:for each="{data.cards}" as="card">
    <headliner:headline record="{card}" />
</f:for>

The label field is the field the backend uses as the name of a record (ctrl.label in the TCA): the header of a content element, the title of a card. In a Content Block it is the labelField of the collection, or else the first text field. If another field is to be the text, name it with textField. Or put the text between the tags, which wins over the field. That is the way if you need something around the text (a link) or want to output it yourself:

<headliner:headline record="{record}">{record -> f:render.text(field: 'header')}</headliner:headline>

The text from a field is output with f:render.text, the one the namespace f has in your template: with visual_editor that is its own ViewHelper, so what an editor can change in the frontend is marked as it is with {record -> f:render.text(...)} in the template (checked with visual_editor in the edit mode: the same ve-editable-text with the table, the uid and the field). A field the record does not have gives no heading, not an empty one, and neither does a label field that is no plain text (a select, a number).

A heading is for a plain text field (input or text without rich text). A rich text field works too, and visual_editor marks it as it does in the template (ve-editable-rich-text), but its paragraphs end up inside the heading, which HTML does not allow: the page module reads such a heading as empty. Use a plain text field for the title, and output a rich text next to the heading. With a header and a rich text field, a template of your own looks like this. The heading is the ViewHelper, the rich text is output as it is, with f:render.text (or f:format.html), and needs nothing else:

<article>
    <headliner:headline record="{record}" />
    {record -> f:render.text(field: 'bodytext')}
</article>

The headings the editor wrote in bodytext (<h3> in the text) are found by the page module as well: they have the badge RTE and, with the site setting headliner.editRteHeadings, a select. Nothing in the template says so. The record names itself in every heading of its rich text fields when it is created for the page module (the listener MarkRichTextHeadings), so it does not matter how the text is output. The same works for a card in a collection: {card -> f:render.text(field: 'text')} next to headliner:headline record="{card}".

The tag comes from the field of the record (header_tag, subheader_tag, or for a card the one field of its table that is a select of tags), the layout class from header_layout, and the page module gets the record, its uid (in a translation the uid of the translation) and the field. A card without a tag of its own is one level below the header of the content element, which is the variable data. The headings in the rich text of a record are marked when the record is created, so they need nothing in the template.

Only record is required. Everything else has a value that is right in most cases; pass it only for the case in the second column.

Argument	Required	When you need it	Without it
`record`	yes	Always. It takes record objects only (`RecordInterface`): an array, such as `{data}` in a template of `fluid_styled_content`, is refused with an error. Use `{record}` there, or `headliner:headline.values`.	(required)
`textField`	no	Only if the text is not in the label field of the table, and there is no content between the tags: `textField="description"`. The text is output with `f:render.text`, so `visual_editor` still marks it.	The label field of the table (the `header` of a content element, the title of a card), `subheader` with `subheader`; content between the tags wins
`subheader`	no	A switch, written `subheader="1"` (or `subheader="true"`): the heading is the subheader of the element and not its header. You write nothing else for it, the text, the tag and the layout follow (see the example below).	The header
`tag`	no	Only to force a tag that the record does not say: `h1` to `h6` or `div` (anything else becomes a `div`). It wins over the record. With `subheader` it is the tag of the subheader.	The tag from the field of the record
`tagField`	no	Only if the table has several fields that are a select of tags, or none of the usual name. Name the one that is meant: `tagField="tag"`.	`header_tag` (`subheader_tag` with `subheader`) if the record has that field, else the one field of the table that is a select with tags and nothing else. If there is none, or several, the heading gets the default tag and no mark, so the page module cannot change it.
`parent`	no	Only for a heading in a record of another table (a card) if the content element is not the variable `data`, or for a subheader that is to be counted from another header. A record object or the array of one; any other type is refused.	The variable `data` of the template, for a record of another table than `tt_content`
`default`	no	Only to say the tag of a heading that has no tag and no layout (an editor chose none, the record has no layout from 1 to 6): a tag (`default="h2"`, `default="div"`) or a layout number from 1 to 6. The tag of the record and its layout win over it.	The setting `defaultHeaderType` of the content element, else `h2`
`offset`	no	Only for another distance than one level below the header of the parent. A negative number goes up (never above `h1`; below `h6` and below a `div` it is a `div`).	1

The default tag, for content without a tag and without a layout, is the setting defaultHeaderType of the content element ({settings.defaultHeaderType} in fluid_styled_content), and h2 if there is none. Name another one with default, for example when a component has a standard tag that applies unless the editor chose one:

<headliner:headline record="{data}" default="{headlineTag}">{headline}</headliner:headline>

The subheader. subheader="1" makes the heading the subheader of the same record. The text comes from the field subheader, the layout class is that of the header, and the tag is, in this order:

the tag you give with tag,
else the field subheader_tag of the record (the choice of the editor),
else one level below the header (offset levels): below its tag h2 an h3, below h6 or a div a div.

<header>
    <headliner:headline record="{record}" />
    <headliner:headline record="{record}" subheader="1" />
</header>

<headliner:headline record="{record}" subheader="1" tag="h4" />

The first pair is the header and its subheader, the tag of the subheader following that of the header unless the editor chose one. The last line forces h4. A subheader the record has no text for (the field subheader is empty) gives no heading.