gecko-dev/dom/base/nsIContent.h
Nicholas Nethercote 2511b2c327 Bug 1267550 (part 2) - Rename MOZ_WARN_UNUSED_RESULT as MOZ_MUST_USE. r=froydnj.
It's an annotation that is used a lot, and should be used even more, so a
shorter name is better.

MozReview-Commit-ID: 1VS4Dney4WX

--HG--
extra : rebase_source : b26919c1b0fcb32e5339adeef5be5becae6032cf
2016-04-27 14:16:50 +10:00

1034 lines
38 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
#ifndef nsIContent_h___
#define nsIContent_h___
#include "mozilla/Attributes.h"
#include "nsCaseTreatment.h" // for enum, cannot be forward-declared
#include "nsINode.h"
// Forward declarations
class nsAString;
class nsIAtom;
class nsIURI;
class nsRuleWalker;
class nsAttrValue;
class nsAttrName;
class nsTextFragment;
class nsIFrame;
class nsXBLBinding;
namespace mozilla {
class EventChainPreVisitor;
namespace dom {
class ShadowRoot;
struct CustomElementData;
} // namespace dom
namespace widget {
struct IMEState;
} // namespace widget
} // namespace mozilla
enum nsLinkState {
eLinkState_Unvisited = 1,
eLinkState_Visited = 2,
eLinkState_NotLink = 3
};
// IID for the nsIContent interface
#define NS_ICONTENT_IID \
{ 0x8e1bab9d, 0x8815, 0x4d2c, \
{ 0xa2, 0x4d, 0x7a, 0xba, 0x52, 0x39, 0xdc, 0x22 } }
/**
* A node of content in a document's content model. This interface
* is supported by all content objects.
*/
class nsIContent : public nsINode {
public:
typedef mozilla::widget::IMEState IMEState;
#ifdef MOZILLA_INTERNAL_API
// If you're using the external API, the only thing you can know about
// nsIContent is that it exists with an IID
explicit nsIContent(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
: nsINode(aNodeInfo)
{
MOZ_ASSERT(mNodeInfo);
SetNodeIsContent();
}
#endif // MOZILLA_INTERNAL_API
NS_DECLARE_STATIC_IID_ACCESSOR(NS_ICONTENT_IID)
/**
* Bind this content node to a tree. If this method throws, the caller must
* call UnbindFromTree() on the node. In the typical case of a node being
* appended to a parent, this will be called after the node has been added to
* the parent's child list and before nsIDocumentObserver notifications for
* the addition are dispatched.
* @param aDocument The new document for the content node. May not be null
* if aParent is null. Must match the current document of
* aParent, if aParent is not null (note that
* aParent->GetUncomposedDoc() can be null, in which case
* this must also be null).
* @param aParent The new parent for the content node. May be null if the
* node is being bound as a direct child of the document.
* @param aBindingParent The new binding parent for the content node.
* This is must either be non-null if a particular
* binding parent is desired or match aParent's binding
* parent.
* @param aCompileEventHandlers whether to initialize the event handlers in
* the document (used by nsXULElement)
* @note either aDocument or aParent must be non-null. If both are null,
* this method _will_ crash.
* @note This method must not be called by consumers of nsIContent on a node
* that is already bound to a tree. Call UnbindFromTree first.
* @note This method will handle rebinding descendants appropriately (eg
* changing their binding parent as needed).
* @note This method does not add the content node to aParent's child list
* @throws NS_ERROR_OUT_OF_MEMORY if that happens
*/
virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
nsIContent* aBindingParent,
bool aCompileEventHandlers) = 0;
/**
* Unbind this content node from a tree. This will set its current document
* and binding parent to null. In the typical case of a node being removed
* from a parent, this will be called after it has been removed from the
* parent's child list and after the nsIDocumentObserver notifications for
* the removal have been dispatched.
* @param aDeep Whether to recursively unbind the entire subtree rooted at
* this node. The only time false should be passed is when the
* parent node of the content is being destroyed.
* @param aNullParent Whether to null out the parent pointer as well. This
* is usually desirable. This argument should only be false while
* recursively calling UnbindFromTree when a subtree is detached.
* @note This method is safe to call on nodes that are not bound to a tree.
*/
virtual void UnbindFromTree(bool aDeep = true,
bool aNullParent = true) = 0;
enum {
/**
* All XBL flattened tree children of the node, as well as :before and
* :after anonymous content and native anonymous children.
*
* @note the result children order is
* 1. :before generated node
* 2. XBL flattened tree children of this node
* 3. native anonymous nodes
* 4. :after generated node
*/
eAllChildren = 0,
/**
* All XBL explicit children of the node (see
* http://www.w3.org/TR/xbl/#explicit3 ), as well as :before and :after
* anonymous content and native anonymous children.
*
* @note the result children order is
* 1. :before generated node
* 2. XBL explicit children of the node
* 3. native anonymous nodes
* 4. :after generated node
*/
eAllButXBL = 1,
/**
* Skip native anonymous content created for placeholder of HTML input,
* used in conjunction with eAllChildren or eAllButXBL.
*/
eSkipPlaceholderContent = 2
};
/**
* Return either the XBL explicit children of the node or the XBL flattened
* tree children of the node, depending on the filter, as well as
* native anonymous children.
*
* @note calling this method with eAllButXBL will return children that are
* also in the eAllButXBL and eAllChildren child lists of other descendants
* of this node in the tree, but those other nodes cannot be reached from the
* eAllButXBL child list.
*/
virtual already_AddRefed<nsINodeList> GetChildren(uint32_t aFilter) = 0;
/**
* Get whether this content is C++-generated anonymous content
* @see nsIAnonymousContentCreator
* @return whether this content is anonymous
*/
bool IsRootOfNativeAnonymousSubtree() const
{
NS_ASSERTION(!HasFlag(NODE_IS_NATIVE_ANONYMOUS_ROOT) ||
(HasFlag(NODE_IS_ANONYMOUS_ROOT) &&
HasFlag(NODE_IS_IN_NATIVE_ANONYMOUS_SUBTREE)),
"Some flags seem to be missing!");
return HasFlag(NODE_IS_NATIVE_ANONYMOUS_ROOT);
}
bool IsRootOfChromeAccessOnlySubtree() const
{
return HasFlag(NODE_IS_NATIVE_ANONYMOUS_ROOT |
NODE_IS_ROOT_OF_CHROME_ONLY_ACCESS);
}
/**
* Makes this content anonymous
* @see nsIAnonymousContentCreator
*/
void SetIsNativeAnonymousRoot()
{
SetFlags(NODE_IS_ANONYMOUS_ROOT | NODE_IS_IN_NATIVE_ANONYMOUS_SUBTREE |
NODE_IS_NATIVE_ANONYMOUS_ROOT);
}
/**
* Returns |this| if it is not chrome-only/native anonymous, otherwise
* first non chrome-only/native anonymous ancestor.
*/
virtual nsIContent* FindFirstNonChromeOnlyAccessContent() const;
/**
* Returns true if and only if this node has a parent, but is not in
* its parent's child list.
*/
bool IsRootOfAnonymousSubtree() const
{
NS_ASSERTION(!IsRootOfNativeAnonymousSubtree() ||
(GetParent() && GetBindingParent() == GetParent()),
"root of native anonymous subtree must have parent equal "
"to binding parent");
NS_ASSERTION(!GetParent() ||
((GetBindingParent() == GetParent()) ==
HasFlag(NODE_IS_ANONYMOUS_ROOT)) ||
// Unfortunately default content for XBL insertion points is
// anonymous content that is bound with the parent of the
// insertion point as the parent but the bound element for the
// binding as the binding parent. So we have to complicate
// the assert a bit here.
(GetBindingParent() &&
(GetBindingParent() == GetParent()->GetBindingParent()) ==
HasFlag(NODE_IS_ANONYMOUS_ROOT)),
"For nodes with parent, flag and GetBindingParent() check "
"should match");
return HasFlag(NODE_IS_ANONYMOUS_ROOT);
}
/**
* Returns true if there is NOT a path through child lists
* from the top of this node's parent chain back to this node or
* if the node is in native anonymous subtree without a parent.
*/
bool IsInAnonymousSubtree() const
{
NS_ASSERTION(!IsInNativeAnonymousSubtree() || GetBindingParent() ||
(!IsInUncomposedDoc() &&
static_cast<nsIContent*>(SubtreeRoot())->IsInNativeAnonymousSubtree()),
"Must have binding parent when in native anonymous subtree which is in document.\n"
"Native anonymous subtree which is not in document must have native anonymous root.");
return IsInNativeAnonymousSubtree() || (!IsInShadowTree() && GetBindingParent() != nullptr);
}
/**
* Return true iff this node is in an HTML document (in the HTML5 sense of
* the term, i.e. not in an XHTML/XML document).
*/
inline bool IsInHTMLDocument() const;
/**
* Get the namespace that this element's tag is defined in
* @return the namespace
*/
inline int32_t GetNameSpaceID() const
{
return mNodeInfo->NamespaceID();
}
inline bool IsHTMLElement() const
{
return IsInNamespace(kNameSpaceID_XHTML);
}
inline bool IsHTMLElement(nsIAtom* aTag) const
{
return mNodeInfo->Equals(aTag, kNameSpaceID_XHTML);
}
template<typename First, typename... Args>
inline bool IsAnyOfHTMLElements(First aFirst, Args... aArgs) const
{
return IsHTMLElement() && IsNodeInternal(aFirst, aArgs...);
}
inline bool IsSVGElement() const
{
return IsInNamespace(kNameSpaceID_SVG);
}
inline bool IsSVGElement(nsIAtom* aTag) const
{
return mNodeInfo->Equals(aTag, kNameSpaceID_SVG);
}
template<typename First, typename... Args>
inline bool IsAnyOfSVGElements(First aFirst, Args... aArgs) const
{
return IsSVGElement() && IsNodeInternal(aFirst, aArgs...);
}
inline bool IsXULElement() const
{
return IsInNamespace(kNameSpaceID_XUL);
}
inline bool IsXULElement(nsIAtom* aTag) const
{
return mNodeInfo->Equals(aTag, kNameSpaceID_XUL);
}
template<typename First, typename... Args>
inline bool IsAnyOfXULElements(First aFirst, Args... aArgs) const
{
return IsXULElement() && IsNodeInternal(aFirst, aArgs...);
}
inline bool IsMathMLElement() const
{
return IsInNamespace(kNameSpaceID_MathML);
}
inline bool IsMathMLElement(nsIAtom* aTag) const
{
return mNodeInfo->Equals(aTag, kNameSpaceID_MathML);
}
template<typename First, typename... Args>
inline bool IsAnyOfMathMLElements(First aFirst, Args... aArgs) const
{
return IsMathMLElement() && IsNodeInternal(aFirst, aArgs...);
}
inline bool IsActiveChildrenElement() const
{
return mNodeInfo->Equals(nsGkAtoms::children, kNameSpaceID_XBL) &&
GetBindingParent();
}
/**
* Set attribute values. All attribute values are assumed to have a
* canonical string representation that can be used for these
* methods. The SetAttr method is assumed to perform a translation
* of the canonical form into the underlying content specific
* form.
*
* @param aNameSpaceID the namespace of the attribute
* @param aName the name of the attribute
* @param aValue the value to set
* @param aNotify specifies how whether or not the document should be
* notified of the attribute change.
*/
nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
const nsAString& aValue, bool aNotify)
{
return SetAttr(aNameSpaceID, aName, nullptr, aValue, aNotify);
}
/**
* Set attribute values. All attribute values are assumed to have a
* canonical String representation that can be used for these
* methods. The SetAttr method is assumed to perform a translation
* of the canonical form into the underlying content specific
* form.
*
* @param aNameSpaceID the namespace of the attribute
* @param aName the name of the attribute
* @param aPrefix the prefix of the attribute
* @param aValue the value to set
* @param aNotify specifies how whether or not the document should be
* notified of the attribute change.
*/
virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
nsIAtom* aPrefix, const nsAString& aValue,
bool aNotify) = 0;
/**
* Get the current value of the attribute. This returns a form that is
* suitable for passing back into SetAttr.
*
* @param aNameSpaceID the namespace of the attr
* @param aName the name of the attr
* @param aResult the value (may legitimately be the empty string) [OUT]
* @returns true if the attribute was set (even when set to empty string)
* false when not set.
*/
bool GetAttr(int32_t aNameSpaceID, nsIAtom* aName,
nsAString& aResult) const;
/**
* Determine if an attribute has been set (empty string or otherwise).
*
* @param aNameSpaceId the namespace id of the attribute
* @param aAttr the attribute name
* @return whether an attribute exists
*/
bool HasAttr(int32_t aNameSpaceID, nsIAtom* aName) const;
/**
* Test whether this content node's given attribute has the given value. If
* the attribute is not set at all, this will return false.
*
* @param aNameSpaceID The namespace ID of the attribute. Must not
* be kNameSpaceID_Unknown.
* @param aName The name atom of the attribute. Must not be null.
* @param aValue The value to compare to.
* @param aCaseSensitive Whether to do a case-sensitive compare on the value.
*/
bool AttrValueIs(int32_t aNameSpaceID,
nsIAtom* aName,
const nsAString& aValue,
nsCaseTreatment aCaseSensitive) const;
/**
* Test whether this content node's given attribute has the given value. If
* the attribute is not set at all, this will return false.
*
* @param aNameSpaceID The namespace ID of the attribute. Must not
* be kNameSpaceID_Unknown.
* @param aName The name atom of the attribute. Must not be null.
* @param aValue The value to compare to. Must not be null.
* @param aCaseSensitive Whether to do a case-sensitive compare on the value.
*/
bool AttrValueIs(int32_t aNameSpaceID,
nsIAtom* aName,
nsIAtom* aValue,
nsCaseTreatment aCaseSensitive) const;
enum {
ATTR_MISSING = -1,
ATTR_VALUE_NO_MATCH = -2
};
/**
* Check whether this content node's given attribute has one of a given
* list of values. If there is a match, we return the index in the list
* of the first matching value. If there was no attribute at all, then
* we return ATTR_MISSING. If there was an attribute but it didn't
* match, we return ATTR_VALUE_NO_MATCH. A non-negative result always
* indicates a match.
*
* @param aNameSpaceID The namespace ID of the attribute. Must not
* be kNameSpaceID_Unknown.
* @param aName The name atom of the attribute. Must not be null.
* @param aValues a nullptr-terminated array of pointers to atom values to test
* against.
* @param aCaseSensitive Whether to do a case-sensitive compare on the values.
* @return ATTR_MISSING, ATTR_VALUE_NO_MATCH or the non-negative index
* indicating the first value of aValues that matched
*/
typedef nsIAtom* const* const AttrValuesArray;
virtual int32_t FindAttrValueIn(int32_t aNameSpaceID,
nsIAtom* aName,
AttrValuesArray* aValues,
nsCaseTreatment aCaseSensitive) const
{
return ATTR_MISSING;
}
/**
* Remove an attribute so that it is no longer explicitly specified.
*
* @param aNameSpaceID the namespace id of the attribute
* @param aAttr the name of the attribute to unset
* @param aNotify specifies whether or not the document should be
* notified of the attribute change
*/
virtual nsresult UnsetAttr(int32_t aNameSpaceID, nsIAtom* aAttr,
bool aNotify) = 0;
/**
* Get the namespace / name / prefix of a given attribute.
*
* @param aIndex the index of the attribute name
* @returns The name at the given index, or null if the index is
* out-of-bounds.
* @note The document returned by NodeInfo()->GetDocument() (if one is
* present) is *not* necessarily the owner document of the element.
* @note The pointer returned by this function is only valid until the
* next call of either GetAttrNameAt or SetAttr on the element.
*/
virtual const nsAttrName* GetAttrNameAt(uint32_t aIndex) const = 0;
/**
* Get the number of all specified attributes.
*
* @return the number of attributes
*/
virtual uint32_t GetAttrCount() const = 0;
/**
* Get direct access (but read only) to the text in the text content.
* NOTE: For elements this is *not* the concatenation of all text children,
* it is simply null;
*/
virtual const nsTextFragment *GetText() = 0;
/**
* Get the length of the text content.
* NOTE: This should not be called on elements.
*/
virtual uint32_t TextLength() const = 0;
/**
* Determines if an event attribute name (such as onclick) is valid for
* a given element type.
* @note calls nsContentUtils::IsEventAttributeName with right flag
* @note overridden by subclasses as needed
* @param aName the event name to look up
*/
virtual bool IsEventAttributeName(nsIAtom* aName)
{
return false;
}
/**
* Set the text to the given value. If aNotify is true then
* the document is notified of the content change.
* NOTE: For elements this always ASSERTS and returns NS_ERROR_FAILURE
*/
virtual nsresult SetText(const char16_t* aBuffer, uint32_t aLength,
bool aNotify) = 0;
/**
* Append the given value to the current text. If aNotify is true then
* the document is notified of the content change.
* NOTE: For elements this always ASSERTS and returns NS_ERROR_FAILURE
*/
virtual nsresult AppendText(const char16_t* aBuffer, uint32_t aLength,
bool aNotify) = 0;
/**
* Set the text to the given value. If aNotify is true then
* the document is notified of the content change.
* NOTE: For elements this always asserts and returns NS_ERROR_FAILURE
*/
nsresult SetText(const nsAString& aStr, bool aNotify)
{
return SetText(aStr.BeginReading(), aStr.Length(), aNotify);
}
/**
* Query method to see if the frame is nothing but whitespace
* NOTE: Always returns false for elements
*/
virtual bool TextIsOnlyWhitespace() = 0;
/**
* Method to see if the text node contains data that is useful
* for a translation: i.e., it consists of more than just whitespace,
* digits and punctuation.
* NOTE: Always returns false for elements.
*/
virtual bool HasTextForTranslation() = 0;
/**
* Append the text content to aResult.
* NOTE: This asserts and returns for elements
*/
virtual void AppendTextTo(nsAString& aResult) = 0;
/**
* Append the text content to aResult.
* NOTE: This asserts and returns for elements
*/
MOZ_MUST_USE
virtual bool AppendTextTo(nsAString& aResult, const mozilla::fallible_t&) = 0;
/**
* Check if this content is focusable and in the current tab order.
* Note: most callers should use nsIFrame::IsFocusable() instead as it
* checks visibility and other layout factors as well.
* Tabbable is indicated by a nonnegative tabindex & is a subset of focusable.
* For example, only the selected radio button in a group is in the
* tab order, unless the radio group has no selection in which case
* all of the visible, non-disabled radio buttons in the group are
* in the tab order. On the other hand, all of the visible, non-disabled
* radio buttons are always focusable via clicking or script.
* Also, depending on either the accessibility.tabfocus pref or
* a system setting (nowadays: Full keyboard access, mac only)
* some widgets may be focusable but removed from the tab order.
* @param [inout, optional] aTabIndex the computed tab index
* In: default tabindex for element (-1 nonfocusable, == 0 focusable)
* Out: computed tabindex
* @param [optional] aTabIndex the computed tab index
* < 0 if not tabbable
* == 0 if in normal tab order
* > 0 can be tabbed to in the order specified by this value
* @return whether the content is focusable via mouse, kbd or script.
*/
bool IsFocusable(int32_t* aTabIndex = nullptr, bool aWithMouse = false);
virtual bool IsFocusableInternal(int32_t* aTabIndex, bool aWithMouse);
/**
* The method focuses (or activates) element that accesskey is bound to. It is
* called when accesskey is activated.
*
* @param aKeyCausesActivation - if true then element should be activated
* @param aIsTrustedEvent - if true then event that is cause of accesskey
* execution is trusted.
* @return true if the focus was changed.
*/
virtual bool PerformAccesskey(bool aKeyCausesActivation,
bool aIsTrustedEvent)
{
return false;
}
/*
* Get desired IME state for the content.
*
* @return The desired IME status for the content.
* This is a combination of an IME enabled value and
* an IME open value of widget::IMEState.
* If you return DISABLED, you should not set the OPEN and CLOSE
* value.
* PASSWORD should be returned only from password editor, this value
* has a special meaning. It is used as alternative of DISABLED.
* PLUGIN should be returned only when plug-in has focus. When a
* plug-in is focused content, we should send native events directly.
* Because we don't process some native events, but they may be needed
* by the plug-in.
*/
virtual IMEState GetDesiredIMEState();
/**
* Gets content node with the binding (or native code, possibly on the
* frame) responsible for our construction (and existence). Used by
* anonymous content (both XBL-generated and native-anonymous).
*
* null for all explicit content (i.e., content reachable from the top
* of its GetParent() chain via child lists).
*
* @return the binding parent
*/
virtual nsIContent *GetBindingParent() const = 0;
/**
* Gets the current XBL binding that is bound to this element.
*
* @return the current binding.
*/
virtual nsXBLBinding *GetXBLBinding() const = 0;
/**
* Sets or unsets an XBL binding for this element. Setting a
* binding on an element that already has a binding will remove the
* old binding.
*
* @param aBinding The binding to bind to this content. If nullptr is
* provided as the argument, then existing binding will be
* removed.
*
* @param aOldBindingManager The old binding manager that contains
* this content if this content was adopted
* to another document.
*/
virtual void SetXBLBinding(nsXBLBinding* aBinding,
nsBindingManager* aOldBindingManager = nullptr) = 0;
/**
* Sets the ShadowRoot binding for this element. The contents of the
* binding is rendered in place of this node's children.
*
* @param aShadowRoot The ShadowRoot to be bound to this element.
*/
virtual void SetShadowRoot(mozilla::dom::ShadowRoot* aShadowRoot) = 0;
/**
* Gets the ShadowRoot binding for this element.
*
* @return The ShadowRoot currently bound to this element.
*/
virtual mozilla::dom::ShadowRoot *GetShadowRoot() const = 0;
/**
* Gets the root of the node tree for this content if it is in a shadow tree.
* This method is called |GetContainingShadow| instead of |GetRootShadowRoot|
* to avoid confusion with |GetShadowRoot|.
*
* @return The ShadowRoot that is the root of the node tree.
*/
virtual mozilla::dom::ShadowRoot *GetContainingShadow() const = 0;
/**
* Gets an array of destination insertion points where this content
* is distributed by web component distribution algorithms.
* The array is created if it does not already exist.
*/
virtual nsTArray<nsIContent*> &DestInsertionPoints() = 0;
/**
* Same as DestInsertionPoints except that this method will return
* null if the array of destination insertion points does not already
* exist.
*/
virtual nsTArray<nsIContent*> *GetExistingDestInsertionPoints() const = 0;
/**
* Gets the insertion parent element of the XBL binding.
* The insertion parent is our one true parent in the transformed DOM.
*
* @return the insertion parent element.
*/
virtual nsIContent *GetXBLInsertionParent() const = 0;
/**
* Sets the insertion parent element of the XBL binding.
*
* @param aContent The insertion parent element.
*/
virtual void SetXBLInsertionParent(nsIContent* aContent) = 0;
/**
* Returns the content node that is the parent of this node in the flattened
* tree. For nodes that are not filtered into an insertion point, this
* simply returns their DOM parent in the original DOM tree.
*
* @return the flattened tree parent
*/
nsIContent *GetFlattenedTreeParent() const;
/**
* Gets the custom element data used by web components custom element.
* Custom element data is created at the first attempt to enqueue a callback.
*
* @return The custom element data or null if none.
*/
virtual mozilla::dom::CustomElementData *GetCustomElementData() const = 0;
/**
* Sets the custom element data, ownership of the
* callback data is taken by this content.
*
* @param aCallbackData The custom element data.
*/
virtual void SetCustomElementData(mozilla::dom::CustomElementData* aData) = 0;
/**
* API to check if this is a link that's traversed in response to user input
* (e.g. a click event). Specializations for HTML/SVG/generic XML allow for
* different types of link in different types of content.
*
* @param aURI Required out param. If this content is a link, a new nsIURI
* set to this link's URI will be passed out.
*
* @note The out param, aURI, is guaranteed to be set to a non-null pointer
* when the return value is true.
*
* XXXjwatt: IMO IsInteractiveLink would be a better name.
*/
virtual bool IsLink(nsIURI** aURI) const = 0;
/**
* Get a pointer to the full href URI (fully resolved and canonicalized,
* since it's an nsIURI object) for link elements.
*
* @return A pointer to the URI or null if the element is not a link or it
* has no HREF attribute.
*/
virtual already_AddRefed<nsIURI> GetHrefURI() const
{
return nullptr;
}
/**
* This method is called when the parser finishes creating the element. This
* particularly means that it has done everything you would expect it to have
* done after it encounters the > at the end of the tag (for HTML or XML).
* This includes setting the attributes, setting the document / form, and
* placing the element into the tree at its proper place.
*
* For container elements, this is called *before* any of the children are
* created or added into the tree.
*
* NOTE: this is currently only called for input and button, in the HTML
* content sink. If you want to call it on your element, modify the content
* sink of your choice to do so. This is an efficiency measure.
*
* If you also need to determine whether the parser is the one creating your
* element (through createElement() or cloneNode() generally) then add a
* uint32_t aFromParser to the NS_NewXXX() constructor for your element and
* have the parser pass the appropriate flags. See HTMLInputElement.cpp and
* nsHTMLContentSink::MakeContentObject().
*
* DO NOT USE THIS METHOD to get around the fact that it's hard to deal with
* attributes dynamically. If you make attributes affect your element from
* this method, it will only happen on initialization and JavaScript will not
* be able to create elements (which requires them to first create the
* element and then call setAttribute() directly, at which point
* DoneCreatingElement() has already been called and is out of the picture).
*/
virtual void DoneCreatingElement()
{
}
/**
* This method is called when the parser begins creating the element's
* children, if any are present.
*
* This is only called for XTF elements currently.
*/
virtual void BeginAddingChildren()
{
}
/**
* This method is called when the parser finishes creating the element's children,
* if any are present.
*
* NOTE: this is currently only called for textarea, select, applet, and
* object elements in the HTML content sink. If you want
* to call it on your element, modify the content sink of your
* choice to do so. This is an efficiency measure.
*
* If you also need to determine whether the parser is the one creating your
* element (through createElement() or cloneNode() generally) then add a
* boolean aFromParser to the NS_NewXXX() constructor for your element and
* have the parser pass true. See HTMLInputElement.cpp and
* nsHTMLContentSink::MakeContentObject().
*
* @param aHaveNotified Whether there has been a
* ContentInserted/ContentAppended notification for this content node
* yet.
*/
virtual void DoneAddingChildren(bool aHaveNotified)
{
}
/**
* For HTML textarea, select, applet, and object elements, returns
* true if all children have been added OR if the element was not
* created by the parser. Returns true for all other elements.
* @returns false if the element was created by the parser and
* it is an HTML textarea, select, applet, or object
* element and not all children have been added.
* @returns true otherwise.
*/
virtual bool IsDoneAddingChildren()
{
return true;
}
/**
* Get the ID of this content node (the atom corresponding to the
* value of the id attribute). This may be null if there is no ID.
*/
nsIAtom* GetID() const {
if (HasID()) {
return DoGetID();
}
return nullptr;
}
/**
* Get the class list of this content node (this corresponds to the
* value of the class attribute). This may be null if there are no
* classes, but that's not guaranteed.
*/
const nsAttrValue* GetClasses() const {
if (HasFlag(NODE_MAY_HAVE_CLASS)) {
return DoGetClasses();
}
return nullptr;
}
/**
* Walk aRuleWalker over the content style rules (presentational
* hint rules) for this content node.
*/
NS_IMETHOD WalkContentStyleRules(nsRuleWalker* aRuleWalker) = 0;
/**
* Should be called when the node can become editable or when it can stop
* being editable (for example when its contentEditable attribute changes,
* when it is moved into an editable parent, ...). If aNotify is true and
* the node is an element, this will notify the state change.
*/
virtual void UpdateEditableState(bool aNotify);
/**
* Destroy this node and its children. Ideally this shouldn't be needed
* but for now we need to do it to break cycles.
*/
virtual void DestroyContent()
{
}
/**
* Saves the form state of this node and its children.
*/
virtual void SaveSubtreeState() = 0;
/**
* Getter and setter for our primary frame pointer. This is the frame that
* is most closely associated with the content. A frame is more closely
* associated with the content than another frame if the one frame contains
* directly or indirectly the other frame (e.g., when a frame is scrolled
* there is a scroll frame that contains the frame being scrolled). This
* frame is always the first continuation.
*
* In the case of absolutely positioned elements and floated elements, this
* frame is the out of flow frame, not the placeholder.
*/
nsIFrame* GetPrimaryFrame() const
{
return (IsInUncomposedDoc() || IsInShadowTree()) ? mPrimaryFrame : nullptr;
}
void SetPrimaryFrame(nsIFrame* aFrame) {
MOZ_ASSERT(IsInUncomposedDoc() || IsInShadowTree(), "This will end badly!");
NS_PRECONDITION(!aFrame || !mPrimaryFrame || aFrame == mPrimaryFrame,
"Losing track of existing primary frame");
mPrimaryFrame = aFrame;
}
nsresult LookupNamespaceURIInternal(const nsAString& aNamespacePrefix,
nsAString& aNamespaceURI) const;
/**
* If this content has independent selection, e.g., if this is input field
* or textarea, this return TRUE. Otherwise, false.
*/
bool HasIndependentSelection();
/**
* If the content is a part of HTML editor, this returns editing
* host content. When the content is in designMode, this returns its body
* element. Also, when the content isn't editable, this returns null.
*/
mozilla::dom::Element* GetEditingHost();
/**
* Determining language. Look at the nearest ancestor element that has a lang
* attribute in the XML namespace or is an HTML/SVG element and has a lang in
* no namespace attribute. Returns false if no language was specified.
*/
bool GetLang(nsAString& aResult) const {
for (const nsIContent* content = this; content; content = content->GetParent()) {
if (content->GetAttrCount() > 0) {
// xml:lang has precedence over lang on HTML elements (see
// XHTML1 section C.7).
bool hasAttr = content->GetAttr(kNameSpaceID_XML, nsGkAtoms::lang,
aResult);
if (!hasAttr && (content->IsHTMLElement() || content->IsSVGElement() ||
content->IsXULElement())) {
hasAttr = content->GetAttr(kNameSpaceID_None, nsGkAtoms::lang,
aResult);
}
NS_ASSERTION(hasAttr || aResult.IsEmpty(),
"GetAttr that returns false should not make string non-empty");
if (hasAttr) {
return true;
}
}
}
return false;
}
// Overloaded from nsINode
virtual already_AddRefed<nsIURI> GetBaseURI(bool aTryUseXHRDocBaseURI = false) const override;
virtual nsresult PreHandleEvent(
mozilla::EventChainPreVisitor& aVisitor) override;
virtual bool IsPurple() = 0;
virtual void RemovePurple() = 0;
virtual bool OwnedOnlyByTheDOMTree() { return false; }
protected:
/**
* Hook for implementing GetID. This is guaranteed to only be
* called if HasID() is true.
*/
nsIAtom* DoGetID() const;
private:
/**
* Hook for implementing GetClasses. This is guaranteed to only be
* called if the NODE_MAY_HAVE_CLASS flag is set.
*/
const nsAttrValue* DoGetClasses() const;
public:
#ifdef DEBUG
/**
* List the content (and anything it contains) out to the given
* file stream. Use aIndent as the base indent during formatting.
*/
virtual void List(FILE* out = stdout, int32_t aIndent = 0) const = 0;
/**
* Dump the content (and anything it contains) out to the given
* file stream. Use aIndent as the base indent during formatting.
*/
virtual void DumpContent(FILE* out = stdout, int32_t aIndent = 0,
bool aDumpAll = true) const = 0;
#endif
/**
* Append to aOutDescription a short (preferably one line) string
* describing the content.
* Currently implemented for elements only.
*/
virtual void Describe(nsAString& aOutDescription) const {
aOutDescription = NS_LITERAL_STRING("(not an element)");
}
enum ETabFocusType {
//eTabFocus_textControlsMask = (1<<0), // unused - textboxes always tabbable
eTabFocus_formElementsMask = (1<<1), // non-text form elements
eTabFocus_linksMask = (1<<2), // links
eTabFocus_any = 1 + (1<<1) + (1<<2) // everything that can be focused
};
// Tab focus model bit field:
static int32_t sTabFocusModel;
// accessibility.tabfocus_applies_to_xul pref - if it is set to true,
// the tabfocus bit field applies to xul elements.
static bool sTabFocusModelAppliesToXUL;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsIContent, NS_ICONTENT_IID)
inline nsIContent* nsINode::AsContent()
{
MOZ_ASSERT(IsContent());
return static_cast<nsIContent*>(this);
}
#define NS_IMPL_FROMCONTENT_HELPER(_class, _check) \
static _class* FromContent(nsIContent* aContent) \
{ \
return aContent->_check ? static_cast<_class*>(aContent) : nullptr; \
} \
static _class* FromContentOrNull(nsIContent* aContent) \
{ \
return aContent ? FromContent(aContent) : nullptr; \
}
#define NS_IMPL_FROMCONTENT(_class, _nsid) \
NS_IMPL_FROMCONTENT_HELPER(_class, IsInNamespace(_nsid))
#define NS_IMPL_FROMCONTENT_WITH_TAG(_class, _nsid, _tag) \
NS_IMPL_FROMCONTENT_HELPER(_class, NodeInfo()->Equals(nsGkAtoms::_tag, _nsid))
#define NS_IMPL_FROMCONTENT_HTML_WITH_TAG(_class, _tag) \
NS_IMPL_FROMCONTENT_WITH_TAG(_class, kNameSpaceID_XHTML, _tag)
#endif /* nsIContent_h___ */