# Extension context information

## Introduction

XForms specifies some context information for events. Orbeon Forms adds further context information to events.

## All events

Orbeon Forms enhances the XML Events `event()` function to take a qualified name as parameter:

```
event($attribute-name as xs:QName) item()*
```

This allows namespacing attribute names, therefore better allowing for extension attributes.

On all events, the following extension attributes are supported:

| Context                   | Type         | Description                                                                                                                                |
| ------------------------- | ------------ | ------------------------------------------------------------------------------------------------------------------------------------------ |
| `xxf:type`                | `xs:string`  | event type (also known as event name), for example `DOMActivate`                                                                           |
| `xxf:targetid`            | `xs:string`  | static id of the event target (`event('xxf:target')` is supported for backward compatibility)                                              |
| `xxf:absolute-targetid`   | `xs:string`  | absolute id of the event target                                                                                                            |
| `xxf:observerid`          | `xs:string`  | static id of the event observer                                                                                                            |
| `xxf:absolute-observerid` | `xs:string`  | absolute id of the event observer                                                                                                          |
| `xxf:bubbles`             | `xs:boolean` | whether the event is allowed to bubble or not                                                                                              |
| `xxf:cancelable`          | `xs:boolean` | whether the event is cancelable or not                                                                                                     |
| `xxf:phase`               | `xs:string`  | current event phase: capture, target, or bubbling                                                                                          |
| `xxf:repeat-indexes`      | `xs:string*` | event target's current repeat indexes, if any, starting from the ancestor repeat                                                           |
| `xxf:repeat-ancestors`    | `xs:string*` | event target's ancestor repeat ids, if any                                                                                                 |
| `xxf:target-prefixes`     | `xs:string*` | event target's id prefixes, if any, starting from the ancestor components. This will be empty unless the target is within an XBL component |

## UI events

These are:

* `DOMActivate`
* `DOMFocusIn`
* `DOMFocusOut`
* `xforms-select`
* `xforms-deselect`
* `xforms-enabled`
* `xforms-disabled`
* `xforms-help`
* `xforms-hint`
* `xforms-valid`
* `xforms-invalid`
* `xforms-required`
* `xforms-optional`
* `xforms-readonly`
* `xforms-readwrite`
* `xforms-value-changed`

The following extension attributes are supported:

| Context                | Type         | Description                                                                                                                                  |
| ---------------------- | ------------ | -------------------------------------------------------------------------------------------------------------------------------------------- |
| `xxf:control-position` | `xs:integer` | event target's position in the user interface. This is the control's static position, i.e. this does not reflect  possible repeat iterations |
| `xxf:binding`          | `node()?`    | event target's single-node binding if any                                                                                                    |
| `xxf:label`            | `xs:string?` | event target's label value if any                                                                                                            |
| `xxf:hint`             | `xs:string?` | event target's hint value if any                                                                                                             |
| `xxf:help`             | `xs:string?` | event target's help value if any                                                                                                             |
| `xxf:alert`            | `xs:string?` | event target's alert value if any                                                                                                            |

On `xforms-value-changed`, the following extension attributes are supported:

* `event('xxf:value')`

  *\[SINCE Orbeon Forms 4.4]*

  The current value (that is, the value after the change) of the control.

On `xforms-select`, the following extension attributes are supported:

* `event('xxf:item-value')`

  When this event is dispatched to in response to a selection control item being selected, returns the value of the selected item.

## Other events

On `xforms-submit-serialize`, the following extension attributes are supported:

| Context             | Type        | Description                                                                                            |
| ------------------- | ----------- | ------------------------------------------------------------------------------------------------------ |
| `xxf:binding`       | `node()?`   | submission's single-node binding if any                                                                |
| `xxf:serialization` | `xs:string` | submission's requested serialization, e.g. `application/xml`, `application/x-www-form-urlencoded`, etc |