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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
use dom::bindings::codegen::InheritTypes::ElementCast;
use dom::bindings::codegen::InheritTypes::HTMLElementCast;
use dom::bindings::codegen::InheritTypes::HTMLIFrameElementCast;
use dom::bindings::codegen::InheritTypes::HTMLImageElementCast;
use dom::bindings::codegen::InheritTypes::HTMLObjectElementCast;
use dom::bindings::codegen::InheritTypes::HTMLStyleElementCast;
use dom::bindings::js::JSRef;
use dom::element::Element;
use dom::element::{ElementTypeId, HTMLImageElementTypeId};
use dom::element::{HTMLIFrameElementTypeId, HTMLObjectElementTypeId, HTMLStyleElementTypeId};
use dom::htmlelement::HTMLElement;
use dom::htmliframeelement::HTMLIFrameElement;
use dom::htmlimageelement::HTMLImageElement;
use dom::htmlobjectelement::HTMLObjectElement;
use dom::htmlstyleelement::HTMLStyleElement;
use dom::node::{Node, ElementNodeTypeId};
use servo_util::str::DOMString;
/// Trait to allow DOM nodes to opt-in to overriding (or adding to) common
/// behaviours. Replicates the effect of C++ virtual methods.
pub trait VirtualMethods {
/// Returns self as the superclass of the implementation for this trait,
/// if any.
fn super_type(&self) -> Option<~VirtualMethods:>;
/// Called when changing or adding attributes, after the attribute's value
/// has been updated.
fn after_set_attr(&mut self, name: DOMString, value: DOMString) {
match self.super_type() {
Some(ref mut s) => s.after_set_attr(name, value),
_ => (),
}
}
/// Called when changing or removing attributes, before any modification
/// has taken place.
fn before_remove_attr(&mut self, name: DOMString, value: DOMString) {
match self.super_type() {
Some(ref mut s) => s.before_remove_attr(name, value),
_ => (),
}
}
/// Called when a Node is appended to a tree that is part of a Document.
fn bind_to_tree(&mut self) {
match self.super_type() {
Some(ref mut s) => s.bind_to_tree(),
_ => (),
}
}
/// Called when a Node is removed from a tree that is part of a Document.
fn unbind_from_tree(&mut self) {
match self.super_type() {
Some(ref mut s) => s.unbind_from_tree(),
_ => (),
}
}
/// Called on the parent when a node is added to its child list.
fn child_inserted(&mut self, child: &JSRef<Node>) {
match self.super_type() {
Some(ref mut s) => s.child_inserted(child),
_ => (),
}
}
}
/// Obtain a VirtualMethods instance for a given Node-derived object. Any
/// method call on the trait object will invoke the corresponding method on the
/// concrete type, propagating up the parent hierarchy unless otherwise
/// interrupted.
pub fn vtable_for<'a>(node: &JSRef<Node>) -> ~VirtualMethods: {
match node.get().type_id {
ElementNodeTypeId(HTMLImageElementTypeId) => {
let element: &JSRef<HTMLImageElement> = HTMLImageElementCast::to_ref(node).unwrap();
~element.clone() as ~VirtualMethods:
}
ElementNodeTypeId(HTMLIFrameElementTypeId) => {
let element: &JSRef<HTMLIFrameElement> = HTMLIFrameElementCast::to_ref(node).unwrap();
~element.clone() as ~VirtualMethods:
}
ElementNodeTypeId(HTMLObjectElementTypeId) => {
let element: &JSRef<HTMLObjectElement> = HTMLObjectElementCast::to_ref(node).unwrap();
~element.clone() as ~VirtualMethods:
}
ElementNodeTypeId(HTMLStyleElementTypeId) => {
let element: &JSRef<HTMLStyleElement> = HTMLStyleElementCast::to_ref(node).unwrap();
~element.clone() as ~VirtualMethods:
}
ElementNodeTypeId(ElementTypeId) => {
let element: &JSRef<Element> = ElementCast::to_ref(node).unwrap();
~element.clone() as ~VirtualMethods:
}
ElementNodeTypeId(_) => {
let element: &JSRef<HTMLElement> = HTMLElementCast::to_ref(node).unwrap();
~element.clone() as ~VirtualMethods:
}
_ => {
~node.clone() as ~VirtualMethods:
}
}
}
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