gecko-dev/layout/generic/nsPageContentFrame.cpp
Ting-Yu Lin 2e869d8f3d Bug 1341009 - Add nsReflowStatus::IsEmpty() assertions to all nsIFrame::Reflow() methods and some reflow helpers, and remove unneeded Reset(). r=dholbert
nsReflowStatus::IsEmpty() assertions are added after DISPLAY_REFLOW in the
beginning of the Reflow().

A few Reflow() implementations have Reset() calls at the end which are left
in place by this patch (with an explanatory comment added to each). These
ending Reset()s are only needed for cases where a non-splittable frame
passes its own nsReflowStatus to a child's reflow method. Just in case the
child leaves a "not fully complete" value in the nsReflowStatus, the
non-splittable parent frame must clear out the nsReflowStatus before
returning, so that its own parent doesn't then try to split it.

MozReview-Commit-ID: 6Jj3jfMAqj4

--HG--
extra : rebase_source : e1fe6a775ad97e16a6d7cc224634ff962ccb0fbf
2017-09-13 18:00:25 +08:00

127 lines
4.8 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 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/. */
#include "nsPageContentFrame.h"
#include "nsCSSFrameConstructor.h"
#include "nsPresContext.h"
#include "nsGkAtoms.h"
#include "nsIPresShell.h"
#include "nsSimplePageSequenceFrame.h"
using namespace mozilla;
nsPageContentFrame*
NS_NewPageContentFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
{
return new (aPresShell) nsPageContentFrame(aContext);
}
NS_IMPL_FRAMEARENA_HELPERS(nsPageContentFrame)
void
nsPageContentFrame::Reflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus)
{
MarkInReflow();
DO_GLOBAL_REFLOW_COUNT("nsPageContentFrame");
DISPLAY_REFLOW(aPresContext, this, aReflowInput, aDesiredSize, aStatus);
MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
if (GetPrevInFlow() && (GetStateBits() & NS_FRAME_FIRST_REFLOW)) {
nsresult rv = aPresContext->PresShell()->FrameConstructor()
->ReplicateFixedFrames(this);
if (NS_FAILED(rv)) {
return;
}
}
// Set our size up front, since some parts of reflow depend on it
// being already set. Note that the computed height may be
// unconstrained; that's ok. Consumers should watch out for that.
nsSize maxSize(aReflowInput.ComputedWidth(),
aReflowInput.ComputedHeight());
SetSize(maxSize);
// A PageContentFrame must always have one child: the canvas frame.
// Resize our frame allowing it only to be as big as we are
// XXX Pay attention to the page's border and padding...
if (mFrames.NotEmpty()) {
nsIFrame* frame = mFrames.FirstChild();
WritingMode wm = frame->GetWritingMode();
LogicalSize logicalSize(wm, maxSize);
ReflowInput kidReflowInput(aPresContext, aReflowInput,
frame, logicalSize);
kidReflowInput.SetComputedBSize(logicalSize.BSize(wm));
// Reflow the page content area
ReflowChild(frame, aPresContext, aDesiredSize, kidReflowInput, 0, 0, 0, aStatus);
// The document element's background should cover the entire canvas, so
// take into account the combined area and any space taken up by
// absolutely positioned elements
nsMargin padding(0,0,0,0);
// XXXbz this screws up percentage padding (sets padding to zero
// in the percentage padding case)
kidReflowInput.mStylePadding->GetPadding(padding);
// This is for shrink-to-fit, and therefore we want to use the
// scrollable overflow, since the purpose of shrink to fit is to
// make the content that ought to be reachable (represented by the
// scrollable overflow) fit in the page.
if (frame->HasOverflowAreas()) {
// The background covers the content area and padding area, so check
// for children sticking outside the child frame's padding edge
nscoord xmost = aDesiredSize.ScrollableOverflow().XMost();
if (xmost > aDesiredSize.Width()) {
nscoord widthToFit = xmost + padding.right +
kidReflowInput.mStyleBorder->GetComputedBorderWidth(eSideRight);
float ratio = float(maxSize.width) / widthToFit;
NS_ASSERTION(ratio >= 0.0 && ratio < 1.0, "invalid shrink-to-fit ratio");
mPD->mShrinkToFitRatio = std::min(mPD->mShrinkToFitRatio, ratio);
}
}
// Place and size the child
FinishReflowChild(frame, aPresContext, aDesiredSize, &kidReflowInput, 0, 0, 0);
NS_ASSERTION(aPresContext->IsDynamic() || !aStatus.IsFullyComplete() ||
!frame->GetNextInFlow(), "bad child flow list");
}
// Reflow our fixed frames
nsReflowStatus fixedStatus;
ReflowAbsoluteFrames(aPresContext, aDesiredSize, aReflowInput, fixedStatus);
NS_ASSERTION(fixedStatus.IsComplete(), "fixed frames can be truncated, but not incomplete");
// Return our desired size
WritingMode wm = aReflowInput.GetWritingMode();
aDesiredSize.ISize(wm) = aReflowInput.ComputedISize();
if (aReflowInput.ComputedBSize() != NS_UNCONSTRAINEDSIZE) {
aDesiredSize.BSize(wm) = aReflowInput.ComputedBSize();
}
FinishAndStoreOverflow(&aDesiredSize);
NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aDesiredSize);
}
void
nsPageContentFrame::AppendDirectlyOwnedAnonBoxes(
nsTArray<OwnedAnonBox>& aResult)
{
MOZ_ASSERT(mFrames.FirstChild(),
"pageContentFrame must have a canvasFrame child");
aResult.AppendElement(mFrames.FirstChild());
}
#ifdef DEBUG_FRAME_DUMP
nsresult
nsPageContentFrame::GetFrameName(nsAString& aResult) const
{
return MakeFrameName(NS_LITERAL_STRING("PageContent"), aResult);
}
#endif