gecko-dev/layout/base/nsFrameManager.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim:cindent:ts=2:et:sw=2:
*
* 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/.
*
* This Original Code has been modified by IBM Corporation. Modifications made
* by IBM described herein are Copyright (c) International Business Machines
* Corporation, 2000. Modifications to Mozilla code or documentation identified
* per MPL Section 3.3
*
* Date Modified by Description of modification
* 04/20/2000 IBM Corp. OS/2 VisualAge build.
*/
/* storage of the frame tree and information about it */
#ifndef _nsFrameManager_h_
#define _nsFrameManager_h_
#include "nsFrameManagerBase.h"
#include "nsFrameList.h"
#include "nsIContent.h"
#include "nsStyleContext.h"
class nsContainerFrame;
class nsPlaceholderFrame;
namespace mozilla {
/**
* Node in a linked list, containing the style for an element that
* does not have a frame but whose parent does have a frame.
*/
struct UndisplayedNode {
UndisplayedNode(nsIContent* aContent, nsStyleContext* aStyle)
: mContent(aContent),
mStyle(aStyle),
mNext(nullptr)
{
MOZ_COUNT_CTOR(mozilla::UndisplayedNode);
}
~UndisplayedNode()
{
MOZ_COUNT_DTOR(mozilla::UndisplayedNode);
// Delete mNext iteratively to avoid blowing up the stack (bug 460461).
UndisplayedNode* cur = mNext;
while (cur) {
UndisplayedNode* next = cur->mNext;
cur->mNext = nullptr;
delete cur;
cur = next;
}
}
nsCOMPtr<nsIContent> mContent;
RefPtr<nsStyleContext> mStyle;
UndisplayedNode* mNext;
};
} // namespace mozilla
/**
* Frame manager interface. The frame manager serves two purposes:
* <li>provides a service for mapping from content to frame and from
* out-of-flow frame to placeholder frame.
* <li>handles structural modifications to the frame model. If the frame model
* lock can be acquired, then the changes are processed immediately; otherwise,
* they're queued and processed later.
*
* Do not add virtual methods (a vtable pointer) or members to this class, or
* else you'll break the validity of the reinterpret_cast in nsIPresShell's
* FrameManager() method.
*/
class nsFrameManager : public nsFrameManagerBase
{
typedef mozilla::layout::FrameChildListID ChildListID;
public:
explicit nsFrameManager(nsIPresShell* aPresShell) {
mPresShell = aPresShell;
MOZ_ASSERT(mPresShell, "need a pres shell");
}
~nsFrameManager();
/*
* After Destroy is called, it is an error to call any FrameManager methods.
* Destroy should be called when the frame tree managed by the frame
* manager is no longer being displayed.
*/
void Destroy();
// Placeholder frame functions
nsPlaceholderFrame* GetPlaceholderFrameFor(const nsIFrame* aFrame);
nsresult
RegisterPlaceholderFrame(nsPlaceholderFrame* aPlaceholderFrame);
void
UnregisterPlaceholderFrame(nsPlaceholderFrame* aPlaceholderFrame);
void ClearPlaceholderFrameMap();
// Mapping undisplayed content
nsStyleContext* GetUndisplayedContent(nsIContent* aContent)
{
if (!mUndisplayedMap) {
return nullptr;
}
return GetStyleContextInMap(mUndisplayedMap, aContent);
}
mozilla::UndisplayedNode*
GetAllUndisplayedContentIn(nsIContent* aParentContent);
void SetUndisplayedContent(nsIContent* aContent,
nsStyleContext* aStyleContext);
void ChangeUndisplayedContent(nsIContent* aContent,
nsStyleContext* aStyleContext)
{
ChangeStyleContextInMap(mUndisplayedMap, aContent, aStyleContext);
}
void ClearUndisplayedContentIn(nsIContent* aContent,
nsIContent* aParentContent);
void ClearAllUndisplayedContentIn(nsIContent* aParentContent);
// display:contents related methods:
/**
* Return the registered display:contents style context for aContent, if any.
*/
nsStyleContext* GetDisplayContentsStyleFor(nsIContent* aContent)
{
if (!mDisplayContentsMap) {
return nullptr;
}
return GetStyleContextInMap(mDisplayContentsMap, aContent);
}
/**
* Return the linked list of UndisplayedNodes containing the registered
* display:contents children of aParentContent, if any.
*/
mozilla::UndisplayedNode* GetAllDisplayContentsIn(nsIContent* aParentContent);
/**
* Register aContent having a display:contents style context.
*/
void SetDisplayContents(nsIContent* aContent,
nsStyleContext* aStyleContext);
/**
* Change the registered style context for aContent to aStyleContext.
*/
void ChangeDisplayContents(nsIContent* aContent,
nsStyleContext* aStyleContext)
{
ChangeStyleContextInMap(mDisplayContentsMap, aContent, aStyleContext);
}
/**
* Unregister the display:contents style context for aContent, if any.
* If found, then also unregister any display:contents and display:none
* style contexts for its descendants.
*/
void ClearDisplayContentsIn(nsIContent* aContent,
nsIContent* aParentContent);
void ClearAllDisplayContentsIn(nsIContent* aParentContent);
// Functions for manipulating the frame model
void AppendFrames(nsContainerFrame* aParentFrame,
ChildListID aListID,
nsFrameList& aFrameList);
void InsertFrames(nsContainerFrame* aParentFrame,
ChildListID aListID,
nsIFrame* aPrevFrame,
nsFrameList& aFrameList);
void RemoveFrame(ChildListID aListID,
nsIFrame* aOldFrame);
/*
* Notification that a frame is about to be destroyed. This allows any
* outstanding references to the frame to be cleaned up.
*/
void NotifyDestroyingFrame(nsIFrame* aFrame);
/*
* Capture/restore frame state for the frame subtree rooted at aFrame.
* aState is the document state storage object onto which each frame
* stores its state. Callers of CaptureFrameState are responsible for
* traversing next continuations of special siblings of aFrame as
* needed; this method will only work with actual frametree descendants
* of aFrame.
*/
void CaptureFrameState(nsIFrame* aFrame,
nsILayoutHistoryState* aState);
void RestoreFrameState(nsIFrame* aFrame,
nsILayoutHistoryState* aState);
/*
* Add/restore state for one frame
*/
void CaptureFrameStateFor(nsIFrame* aFrame,
nsILayoutHistoryState* aState);
void RestoreFrameStateFor(nsIFrame* aFrame,
nsILayoutHistoryState* aState);
protected:
static nsStyleContext* GetStyleContextInMap(UndisplayedMap* aMap,
nsIContent* aContent);
static mozilla::UndisplayedNode*
GetAllUndisplayedNodesInMapFor(UndisplayedMap* aMap,
nsIContent* aParentContent);
static void SetStyleContextInMap(UndisplayedMap* aMap,
nsIContent* aContent,
nsStyleContext* aStyleContext);
static void ChangeStyleContextInMap(UndisplayedMap* aMap,
nsIContent* aContent,
nsStyleContext* aStyleContext);
};
#endif