gecko-dev/layout/generic/nsFirstLetterFrame.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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* The contents of this file are subject to the Mozilla Public License Version
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*
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* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
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* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
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* Contributor(s):
*
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* either of the GNU General Public License Version 2 or later (the "GPL"),
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/* rendering object for CSS :first-letter pseudo-element */
#include "nsCOMPtr.h"
#include "nsFirstLetterFrame.h"
#include "nsPresContext.h"
#include "nsStyleContext.h"
#include "nsIContent.h"
#include "nsLineLayout.h"
#include "nsGkAtoms.h"
#include "nsAutoPtr.h"
#include "nsStyleSet.h"
#include "nsFrameManager.h"
#include "nsPlaceholderFrame.h"
#include "nsCSSFrameConstructor.h"
nsIFrame*
NS_NewFirstLetterFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
{
return new (aPresShell) nsFirstLetterFrame(aContext);
}
NS_IMPL_FRAMEARENA_HELPERS(nsFirstLetterFrame)
#ifdef NS_DEBUG
NS_IMETHODIMP
nsFirstLetterFrame::GetFrameName(nsAString& aResult) const
{
return MakeFrameName(NS_LITERAL_STRING("Letter"), aResult);
}
#endif
nsIAtom*
nsFirstLetterFrame::GetType() const
{
return nsGkAtoms::letterFrame;
}
PRIntn
nsFirstLetterFrame::GetSkipSides() const
{
return 0;
}
NS_IMETHODIMP
nsFirstLetterFrame::Init(nsIContent* aContent,
nsIFrame* aParent,
nsIFrame* aPrevInFlow)
{
nsRefPtr<nsStyleContext> newSC;
if (aPrevInFlow) {
// Get proper style context for ourselves. We're creating the frame
// that represents everything *except* the first letter, so just create
// a style context like we would for a text node.
nsStyleContext* parentStyleContext = mStyleContext->GetParent();
if (parentStyleContext) {
newSC = mStyleContext->GetRuleNode()->GetPresContext()->StyleSet()->
ResolveStyleForNonElement(parentStyleContext);
if (newSC)
SetStyleContextWithoutNotification(newSC);
}
}
return nsFirstLetterFrameSuper::Init(aContent, aParent, aPrevInFlow);
}
NS_IMETHODIMP
nsFirstLetterFrame::SetInitialChildList(nsIAtom* aListName,
nsFrameList& aChildList)
{
nsFrameManager *frameManager = PresContext()->FrameManager();
for (nsFrameList::Enumerator e(aChildList); !e.AtEnd(); e.Next()) {
NS_ASSERTION(e.get()->GetParent() == this, "Unexpected parent");
frameManager->ReparentStyleContext(e.get());
}
mFrames.SetFrames(aChildList);
return NS_OK;
}
NS_IMETHODIMP
nsFirstLetterFrame::GetChildFrameContainingOffset(PRInt32 inContentOffset,
PRBool inHint,
PRInt32* outFrameContentOffset,
nsIFrame **outChildFrame)
{
nsIFrame *kid = mFrames.FirstChild();
if (kid)
{
return kid->GetChildFrameContainingOffset(inContentOffset, inHint, outFrameContentOffset, outChildFrame);
}
else
return nsFrame::GetChildFrameContainingOffset(inContentOffset, inHint, outFrameContentOffset, outChildFrame);
}
// Needed for non-floating first-letter frames and for the continuations
// following the first-letter that we also use nsFirstLetterFrame for.
/* virtual */ void
nsFirstLetterFrame::AddInlineMinWidth(nsIRenderingContext *aRenderingContext,
nsIFrame::InlineMinWidthData *aData)
{
DoInlineIntrinsicWidth(aRenderingContext, aData, nsLayoutUtils::MIN_WIDTH);
}
// Needed for non-floating first-letter frames and for the continuations
// following the first-letter that we also use nsFirstLetterFrame for.
/* virtual */ void
nsFirstLetterFrame::AddInlinePrefWidth(nsIRenderingContext *aRenderingContext,
nsIFrame::InlinePrefWidthData *aData)
{
DoInlineIntrinsicWidth(aRenderingContext, aData, nsLayoutUtils::PREF_WIDTH);
}
// Needed for floating first-letter frames.
/* virtual */ nscoord
nsFirstLetterFrame::GetMinWidth(nsIRenderingContext *aRenderingContext)
{
return nsLayoutUtils::MinWidthFromInline(this, aRenderingContext);
}
// Needed for floating first-letter frames.
/* virtual */ nscoord
nsFirstLetterFrame::GetPrefWidth(nsIRenderingContext *aRenderingContext)
{
return nsLayoutUtils::PrefWidthFromInline(this, aRenderingContext);
}
/* virtual */ nsSize
nsFirstLetterFrame::ComputeSize(nsIRenderingContext *aRenderingContext,
nsSize aCBSize, nscoord aAvailableWidth,
nsSize aMargin, nsSize aBorder, nsSize aPadding,
PRBool aShrinkWrap)
{
if (GetPrevInFlow()) {
// We're wrapping the text *after* the first letter, so behave like an
// inline frame.
return nsSize(NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE);
}
return nsFirstLetterFrameSuper::ComputeSize(aRenderingContext,
aCBSize, aAvailableWidth, aMargin, aBorder, aPadding, aShrinkWrap);
}
NS_IMETHODIMP
nsFirstLetterFrame::Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aMetrics,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aReflowStatus)
{
DO_GLOBAL_REFLOW_COUNT("nsFirstLetterFrame");
DISPLAY_REFLOW(aPresContext, this, aReflowState, aMetrics, aReflowStatus);
nsresult rv = NS_OK;
// Grab overflow list
DrainOverflowFrames(aPresContext);
nsIFrame* kid = mFrames.FirstChild();
// Setup reflow state for our child
nsSize availSize(aReflowState.availableWidth, aReflowState.availableHeight);
const nsMargin& bp = aReflowState.mComputedBorderPadding;
nscoord lr = bp.left + bp.right;
nscoord tb = bp.top + bp.bottom;
NS_ASSERTION(availSize.width != NS_UNCONSTRAINEDSIZE,
"should no longer use unconstrained widths");
availSize.width -= lr;
if (NS_UNCONSTRAINEDSIZE != availSize.height) {
availSize.height -= tb;
}
// Reflow the child
if (!aReflowState.mLineLayout) {
// When there is no lineLayout provided, we provide our own. The
// only time that the first-letter-frame is not reflowing in a
// line context is when its floating.
nsHTMLReflowState rs(aPresContext, aReflowState, kid, availSize);
nsLineLayout ll(aPresContext, nsnull, &aReflowState, nsnull);
ll.BeginLineReflow(bp.left, bp.top, availSize.width, NS_UNCONSTRAINEDSIZE,
PR_FALSE, PR_TRUE);
rs.mLineLayout = &ll;
ll.SetInFirstLetter(PR_TRUE);
ll.SetFirstLetterStyleOK(PR_TRUE);
kid->WillReflow(aPresContext);
kid->Reflow(aPresContext, aMetrics, rs, aReflowStatus);
ll.EndLineReflow();
ll.SetInFirstLetter(PR_FALSE);
}
else {
// Pretend we are a span and reflow the child frame
nsLineLayout* ll = aReflowState.mLineLayout;
PRBool pushedFrame;
ll->SetInFirstLetter(
mStyleContext->GetPseudo() == nsCSSPseudoElements::firstLetter);
ll->BeginSpan(this, &aReflowState, bp.left, availSize.width);
ll->ReflowFrame(kid, aReflowStatus, &aMetrics, pushedFrame);
ll->EndSpan(this);
ll->SetInFirstLetter(PR_FALSE);
}
// Place and size the child and update the output metrics
kid->SetRect(nsRect(bp.left, bp.top, aMetrics.width, aMetrics.height));
kid->FinishAndStoreOverflow(&aMetrics);
kid->DidReflow(aPresContext, nsnull, NS_FRAME_REFLOW_FINISHED);
aMetrics.width += lr;
aMetrics.height += tb;
aMetrics.ascent += bp.top;
mBaseline = aMetrics.ascent;
// Ensure that the overflow rect contains the child textframe's overflow rect.
// Note that if this is floating, the overline/underline drawable area is in
// the overflow rect of the child textframe.
aMetrics.UnionOverflowAreasWithDesiredBounds();
ConsiderChildOverflow(aMetrics.mOverflowAreas, kid);
// Create a continuation or remove existing continuations based on
// the reflow completion status.
if (NS_FRAME_IS_COMPLETE(aReflowStatus)) {
if (aReflowState.mLineLayout) {
aReflowState.mLineLayout->SetFirstLetterStyleOK(PR_FALSE);
}
nsIFrame* kidNextInFlow = kid->GetNextInFlow();
if (kidNextInFlow) {
// Remove all of the childs next-in-flows
static_cast<nsContainerFrame*>(kidNextInFlow->GetParent())
->DeleteNextInFlowChild(aPresContext, kidNextInFlow, PR_TRUE);
}
}
else {
// Create a continuation for the child frame if it doesn't already
// have one.
if (!GetStyleDisplay()->IsFloating()) {
nsIFrame* nextInFlow;
rv = CreateNextInFlow(aPresContext, kid, nextInFlow);
if (NS_FAILED(rv)) {
return rv;
}
// And then push it to our overflow list
const nsFrameList& overflow = mFrames.RemoveFramesAfter(kid);
if (overflow.NotEmpty()) {
SetOverflowFrames(aPresContext, overflow);
}
} else if (!kid->GetNextInFlow()) {
// For floating first letter frames (if a continuation wasn't already
// created for us) we need to put the continuation with the rest of the
// text that the first letter frame was made out of.
nsIFrame* continuation;
rv = CreateContinuationForFloatingParent(aPresContext, kid,
&continuation, PR_TRUE);
}
}
FinishAndStoreOverflow(&aMetrics);
NS_FRAME_SET_TRUNCATION(aReflowStatus, aReflowState, aMetrics);
return rv;
}
/* virtual */ PRBool
nsFirstLetterFrame::CanContinueTextRun() const
{
// We can continue a text run through a first-letter frame.
return PR_TRUE;
}
nsresult
nsFirstLetterFrame::CreateContinuationForFloatingParent(nsPresContext* aPresContext,
nsIFrame* aChild,
nsIFrame** aContinuation,
PRBool aIsFluid)
{
NS_ASSERTION(GetStyleDisplay()->IsFloating(),
"can only call this on floating first letter frames");
NS_PRECONDITION(aContinuation, "bad args");
*aContinuation = nsnull;
nsresult rv = NS_OK;
nsIPresShell* presShell = aPresContext->PresShell();
nsPlaceholderFrame* placeholderFrame =
presShell->FrameManager()->GetPlaceholderFrameFor(this);
nsIFrame* parent = placeholderFrame->GetParent();
nsIFrame* continuation;
rv = presShell->FrameConstructor()->
CreateContinuingFrame(aPresContext, aChild, parent, &continuation, aIsFluid);
if (NS_FAILED(rv) || !continuation) {
return rv;
}
// The continuation will have gotten the first letter style from it's
// prev continuation, so we need to repair the style context so it
// doesn't have the first letter styling.
nsStyleContext* parentSC = this->GetStyleContext()->GetParent();
if (parentSC) {
nsRefPtr<nsStyleContext> newSC;
newSC = presShell->StyleSet()->ResolveStyleForNonElement(parentSC);
if (newSC) {
continuation->SetStyleContext(newSC);
}
}
//XXX Bidi may not be involved but we have to use the list name
// nsGkAtoms::nextBidi because this is just like creating a continuation
// except we have to insert it in a different place and we don't want a
// reflow command to try to be issued.
nsFrameList temp(continuation, continuation);
rv = parent->InsertFrames(nsGkAtoms::nextBidi, placeholderFrame, temp);
*aContinuation = continuation;
return rv;
}
void
nsFirstLetterFrame::DrainOverflowFrames(nsPresContext* aPresContext)
{
nsAutoPtr<nsFrameList> overflowFrames;
// Check for an overflow list with our prev-in-flow
nsFirstLetterFrame* prevInFlow = (nsFirstLetterFrame*)GetPrevInFlow();
if (nsnull != prevInFlow) {
overflowFrames = prevInFlow->StealOverflowFrames();
if (overflowFrames) {
NS_ASSERTION(mFrames.IsEmpty(), "bad overflow list");
// When pushing and pulling frames we need to check for whether any
// views need to be reparented.
nsHTMLContainerFrame::ReparentFrameViewList(aPresContext, *overflowFrames,
prevInFlow, this);
mFrames.InsertFrames(this, nsnull, *overflowFrames);
}
}
// It's also possible that we have an overflow list for ourselves
overflowFrames = StealOverflowFrames();
if (overflowFrames) {
NS_ASSERTION(mFrames.NotEmpty(), "overflow list w/o frames");
mFrames.AppendFrames(nsnull, *overflowFrames);
}
// Now repair our first frames style context (since we only reflow
// one frame there is no point in doing any other ones until they
// are reflowed)
nsIFrame* kid = mFrames.FirstChild();
if (kid) {
nsRefPtr<nsStyleContext> sc;
nsIContent* kidContent = kid->GetContent();
if (kidContent) {
NS_ASSERTION(kidContent->IsNodeOfType(nsINode::eTEXT),
"should contain only text nodes");
sc = aPresContext->StyleSet()->ResolveStyleForNonElement(mStyleContext);
if (sc) {
kid->SetStyleContext(sc);
}
}
}
}
nscoord
nsFirstLetterFrame::GetBaseline() const
{
return mBaseline;
}