зеркало из https://github.com/mozilla/gecko-dev.git
123 строки
4.6 KiB
C++
123 строки
4.6 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/. */
|
|
|
|
/*
|
|
* base class for rendering objects that can be split across lines,
|
|
* columns, or pages
|
|
*/
|
|
|
|
#ifndef nsSplittableFrame_h___
|
|
#define nsSplittableFrame_h___
|
|
|
|
#include "mozilla/Attributes.h"
|
|
#include "nsFrame.h"
|
|
|
|
// Derived class that allows splitting
|
|
class nsSplittableFrame : public nsFrame
|
|
{
|
|
public:
|
|
NS_DECL_ABSTRACT_FRAME(nsSplittableFrame)
|
|
|
|
virtual void Init(nsIContent* aContent,
|
|
nsContainerFrame* aParent,
|
|
nsIFrame* aPrevInFlow) override;
|
|
|
|
virtual nsSplittableType GetSplittableType() const override;
|
|
|
|
virtual void DestroyFrom(nsIFrame* aDestructRoot, PostDestroyData& aPostDestroyData) override;
|
|
|
|
/*
|
|
* Frame continuations can be either fluid or not:
|
|
* Fluid continuations ("in-flows") are the result of line breaking,
|
|
* column breaking, or page breaking.
|
|
* Other (non-fluid) continuations can be the result of BiDi frame splitting.
|
|
* A "flow" is a chain of fluid continuations.
|
|
*/
|
|
|
|
// Get the previous/next continuation, regardless of its type (fluid or non-fluid).
|
|
virtual nsIFrame* GetPrevContinuation() const override;
|
|
virtual nsIFrame* GetNextContinuation() const override;
|
|
|
|
// Set a previous/next non-fluid continuation.
|
|
virtual void SetPrevContinuation(nsIFrame*) override;
|
|
virtual void SetNextContinuation(nsIFrame*) override;
|
|
|
|
// Get the first/last continuation for this frame.
|
|
virtual nsIFrame* FirstContinuation() const override;
|
|
virtual nsIFrame* LastContinuation() const override;
|
|
|
|
#ifdef DEBUG
|
|
// Can aFrame2 be reached from aFrame1 by following prev/next continuations?
|
|
static bool IsInPrevContinuationChain(nsIFrame* aFrame1, nsIFrame* aFrame2);
|
|
static bool IsInNextContinuationChain(nsIFrame* aFrame1, nsIFrame* aFrame2);
|
|
#endif
|
|
|
|
// Get the previous/next continuation, only if it is fluid (an "in-flow").
|
|
nsIFrame* GetPrevInFlow() const;
|
|
nsIFrame* GetNextInFlow() const;
|
|
|
|
virtual nsIFrame* GetPrevInFlowVirtual() const override { return GetPrevInFlow(); }
|
|
virtual nsIFrame* GetNextInFlowVirtual() const override { return GetNextInFlow(); }
|
|
|
|
// Set a previous/next fluid continuation.
|
|
virtual void SetPrevInFlow(nsIFrame*) override;
|
|
virtual void SetNextInFlow(nsIFrame*) override;
|
|
|
|
// Get the first/last frame in the current flow.
|
|
virtual nsIFrame* FirstInFlow() const override;
|
|
virtual nsIFrame* LastInFlow() const override;
|
|
|
|
// Remove the frame from the flow. Connects the frame's prev-in-flow
|
|
// and its next-in-flow. This should only be called in frame Destroy() methods.
|
|
static void RemoveFromFlow(nsIFrame* aFrame);
|
|
|
|
protected:
|
|
nsSplittableFrame(ComputedStyle* aStyle, ClassID aID)
|
|
: nsFrame(aStyle, aID)
|
|
, mPrevContinuation(nullptr)
|
|
, mNextContinuation(nullptr)
|
|
{}
|
|
|
|
/**
|
|
* Return the sum of the block-axis content size of our prev-in-flows.
|
|
* @param aWM a writing-mode to determine the block-axis
|
|
*
|
|
* @note (bz) This makes laying out a splittable frame with N in-flows
|
|
* O(N^2)! So, use this function with caution and minimize the number
|
|
* of calls to this method.
|
|
*/
|
|
nscoord ConsumedBSize(mozilla::WritingMode aWM) const;
|
|
|
|
/**
|
|
* Retrieve the effective computed block size of this frame, which is the
|
|
* computed block size, minus the block size consumed by any previous in-flows.
|
|
*/
|
|
nscoord GetEffectiveComputedBSize(const ReflowInput& aReflowInput,
|
|
nscoord aConsumed = NS_INTRINSICSIZE) const;
|
|
|
|
/**
|
|
* @see nsIFrame::GetLogicalSkipSides()
|
|
*/
|
|
virtual LogicalSides GetLogicalSkipSides(const ReflowInput* aReflowInput = nullptr) const override;
|
|
|
|
/**
|
|
* A faster version of GetLogicalSkipSides() that is intended to be used
|
|
* inside Reflow before it's known if |this| frame will be COMPLETE or not.
|
|
* It returns a result that assumes this fragment is the last and thus
|
|
* should apply the block-end border/padding etc (except for "true" overflow
|
|
* containers which always skip block sides). You're then expected to
|
|
* recalculate the block-end side (as needed) when you know |this| frame's
|
|
* reflow status is INCOMPLETE.
|
|
* This method is intended for frames that breaks in the block axis.
|
|
*/
|
|
LogicalSides PreReflowBlockLevelLogicalSkipSides() const;
|
|
|
|
nsIFrame* mPrevContinuation;
|
|
nsIFrame* mNextContinuation;
|
|
};
|
|
|
|
#endif /* nsSplittableFrame_h___ */
|