The Tor Browser: layout/generic/nsPlaceholderFrame.cpp@b8a032363ba2

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

     2 /* This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 /*

     7  * rendering object for the point that anchors out-of-flow rendering

     8  * objects such as floats and absolutely positioned elements

     9  */

    11 #include "nsPlaceholderFrame.h"

    13 #include "nsDisplayList.h"

    14 #include "nsFrameManager.h"

    15 #include "nsLayoutUtils.h"

    16 #include "nsPresContext.h"

    17 #include "nsRenderingContext.h"

    18 #include "nsIFrameInlines.h"

    20 nsIFrame*

    21 NS_NewPlaceholderFrame(nsIPresShell* aPresShell, nsStyleContext* aContext,

    22                        nsFrameState aTypeBit)

    23 {

    24   return new (aPresShell) nsPlaceholderFrame(aContext, aTypeBit);

    25 }

    27 NS_IMPL_FRAMEARENA_HELPERS(nsPlaceholderFrame)

    29 #ifdef DEBUG

    30 NS_QUERYFRAME_HEAD(nsPlaceholderFrame)

    31   NS_QUERYFRAME_ENTRY(nsPlaceholderFrame)

    32 NS_QUERYFRAME_TAIL_INHERITING(nsFrame)

    33 #endif

    35 /* virtual */ nsSize

    36 nsPlaceholderFrame::GetMinSize(nsBoxLayoutState& aBoxLayoutState)

    37 {

    38   nsSize size(0, 0);

    39   DISPLAY_MIN_SIZE(this, size);

    40   return size;

    41 }

    43 /* virtual */ nsSize

    44 nsPlaceholderFrame::GetPrefSize(nsBoxLayoutState& aBoxLayoutState)

    45 {

    46   nsSize size(0, 0);

    47   DISPLAY_PREF_SIZE(this, size);

    48   return size;

    49 }

    51 /* virtual */ nsSize

    52 nsPlaceholderFrame::GetMaxSize(nsBoxLayoutState& aBoxLayoutState)

    53 {

    54   nsSize size(NS_INTRINSICSIZE, NS_INTRINSICSIZE);

    55   DISPLAY_MAX_SIZE(this, size);

    56   return size;

    57 }

    59 /* virtual */ void

    60 nsPlaceholderFrame::AddInlineMinWidth(nsRenderingContext* aRenderingContext,

    61                                       nsIFrame::InlineMinWidthData* aData)

    62 {

    63   // Override AddInlineMinWith so that *nothing* happens.  In

    64   // particular, we don't want to zero out |aData->trailingWhitespace|,

    65   // since nsLineLayout skips placeholders when trimming trailing

    66   // whitespace, and we don't want to set aData->skipWhitespace to

    67   // false.

    69   // ...but push floats onto the list

    70   if (mOutOfFlowFrame->IsFloating()) {

    71     nscoord floatWidth =

    72       nsLayoutUtils::IntrinsicForContainer(aRenderingContext,

    73                                            mOutOfFlowFrame,

    74                                            nsLayoutUtils::MIN_WIDTH);

    75     aData->floats.AppendElement(

    76       InlineIntrinsicWidthData::FloatInfo(mOutOfFlowFrame, floatWidth));

    77   }

    78 }

    80 /* virtual */ void

    81 nsPlaceholderFrame::AddInlinePrefWidth(nsRenderingContext* aRenderingContext,

    82                                        nsIFrame::InlinePrefWidthData* aData)

    83 {

    84   // Override AddInlinePrefWith so that *nothing* happens.  In

    85   // particular, we don't want to zero out |aData->trailingWhitespace|,

    86   // since nsLineLayout skips placeholders when trimming trailing

    87   // whitespace, and we don't want to set aData->skipWhitespace to

    88   // false.

    90   // ...but push floats onto the list

    91   if (mOutOfFlowFrame->IsFloating()) {

    92     nscoord floatWidth =

    93       nsLayoutUtils::IntrinsicForContainer(aRenderingContext,

    94                                            mOutOfFlowFrame,

    95                                            nsLayoutUtils::PREF_WIDTH);

    96     aData->floats.AppendElement(

    97       InlineIntrinsicWidthData::FloatInfo(mOutOfFlowFrame, floatWidth));

    98   }

    99 }

   101 nsresult

   102 nsPlaceholderFrame::Reflow(nsPresContext*           aPresContext,

   103                            nsHTMLReflowMetrics&     aDesiredSize,

   104                            const nsHTMLReflowState& aReflowState,

   105                            nsReflowStatus&          aStatus)

   106 {

   107 #ifdef DEBUG

   108   // We should be getting reflowed before our out-of-flow.

   109   // If this is our first reflow, and our out-of-flow has already received its

   110   // first reflow (before us), complain.

   111   // XXXdholbert This "look for a previous continuation or IB-split sibling"

   112   // code could use nsLayoutUtils::GetPrevContinuationOrIBSplitSibling(), if

   113   // we ever add a function like that. (We currently have a "Next" version.)

   114   if ((GetStateBits() & NS_FRAME_FIRST_REFLOW) &&

   115       !(mOutOfFlowFrame->GetStateBits() & NS_FRAME_FIRST_REFLOW)) {

   117     // Unfortunately, this can currently happen when the placeholder is in a

   118     // later continuation or later IB-split sibling than its out-of-flow (as

   119     // is the case in some of our existing unit tests). So for now, in that

   120     // case, we'll warn instead of asserting.

   121     bool isInContinuationOrIBSplit = false;

   122     nsIFrame* ancestor = this;

   123     while ((ancestor = ancestor->GetParent())) {

   124       if (ancestor->GetPrevContinuation() ||

   125           ancestor->Properties().Get(IBSplitPrevSibling())) {

   126         isInContinuationOrIBSplit = true;

   127         break;

   128       }

   129     }

   131     if (isInContinuationOrIBSplit) {

   132       NS_WARNING("Out-of-flow frame got reflowed before its placeholder");

   133     } else {

   134       NS_ERROR("Out-of-flow frame got reflowed before its placeholder");

   135     }

   136   }

   137 #endif

   139   DO_GLOBAL_REFLOW_COUNT("nsPlaceholderFrame");

   140   DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);

   141   aDesiredSize.Width() = 0;

   142   aDesiredSize.Height() = 0;

   144   aStatus = NS_FRAME_COMPLETE;

   145   NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);

   146   return NS_OK;

   147 }

   149 void

   150 nsPlaceholderFrame::DestroyFrom(nsIFrame* aDestructRoot)

   151 {

   152   nsIFrame* oof = mOutOfFlowFrame;

   153   if (oof) {

   154     // Unregister out-of-flow frame

   155     nsFrameManager* fm = PresContext()->GetPresShell()->FrameManager();

   156     fm->UnregisterPlaceholderFrame(this);

   157     mOutOfFlowFrame = nullptr;

   158     // If aDestructRoot is not an ancestor of the out-of-flow frame,

   159     // then call RemoveFrame on it here.

   160     // Also destroy it here if it's a popup frame. (Bug 96291)

   161     if ((GetStateBits() & PLACEHOLDER_FOR_POPUP) ||

   162         !nsLayoutUtils::IsProperAncestorFrame(aDestructRoot, oof)) {

   163       ChildListID listId = nsLayoutUtils::GetChildListNameFor(oof);

   164       fm->RemoveFrame(listId, oof);

   165     }

   166     // else oof will be destroyed by its parent

   167   }

   169   nsFrame::DestroyFrom(aDestructRoot);

   170 }

   172 nsIAtom*

   173 nsPlaceholderFrame::GetType() const

   174 {

   175   return nsGkAtoms::placeholderFrame;

   176 }

   178 /* virtual */ bool

   179 nsPlaceholderFrame::CanContinueTextRun() const

   180 {

   181   if (!mOutOfFlowFrame) {

   182     return false;

   183   }

   184   // first-letter frames can continue text runs, and placeholders for floated

   185   // first-letter frames can too

   186   return mOutOfFlowFrame->CanContinueTextRun();

   187 }

   189 nsIFrame*

   190 nsPlaceholderFrame::GetParentStyleContextFrame() const

   191 {

   192   NS_PRECONDITION(GetParent(), "How can we not have a parent here?");

   194   // Lie about our pseudo so we can step out of all anon boxes and

   195   // pseudo-elements.  The other option would be to reimplement the

   196   // {ib} split gunk here.

   197   return CorrectStyleParentFrame(GetParent(), nsGkAtoms::placeholderFrame);

   198 }

   201 #ifdef DEBUG

   202 static void

   203 PaintDebugPlaceholder(nsIFrame* aFrame, nsRenderingContext* aCtx,

   204                       const nsRect& aDirtyRect, nsPoint aPt)

   205 {

   206   aCtx->SetColor(NS_RGB(0, 255, 255));

   207   nscoord x = nsPresContext::CSSPixelsToAppUnits(-5);

   208   aCtx->FillRect(aPt.x + x, aPt.y,

   209                  nsPresContext::CSSPixelsToAppUnits(13),

   210                  nsPresContext::CSSPixelsToAppUnits(3));

   211   nscoord y = nsPresContext::CSSPixelsToAppUnits(-10);

   212   aCtx->FillRect(aPt.x, aPt.y + y,

   213                  nsPresContext::CSSPixelsToAppUnits(3),

   214                  nsPresContext::CSSPixelsToAppUnits(10));

   215 }

   216 #endif // DEBUG

   218 #if defined(DEBUG) || (defined(MOZ_REFLOW_PERF_DSP) && defined(MOZ_REFLOW_PERF))

   220 void

   221 nsPlaceholderFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,

   222                                      const nsRect&           aDirtyRect,

   223                                      const nsDisplayListSet& aLists)

   224 {

   225   DO_GLOBAL_REFLOW_COUNT_DSP("nsPlaceholderFrame");

   227 #ifdef DEBUG

   228   if (GetShowFrameBorders()) {

   229     aLists.Outlines()->AppendNewToTop(

   230       new (aBuilder) nsDisplayGeneric(aBuilder, this, PaintDebugPlaceholder,

   231                                       "DebugPlaceholder",

   232                                       nsDisplayItem::TYPE_DEBUG_PLACEHOLDER));

   233   }

   234 #endif

   235 }

   236 #endif // DEBUG || (MOZ_REFLOW_PERF_DSP && MOZ_REFLOW_PERF)

   238 #ifdef DEBUG_FRAME_DUMP

   239 nsresult

   240 nsPlaceholderFrame::GetFrameName(nsAString& aResult) const

   241 {

   242   return MakeFrameName(NS_LITERAL_STRING("Placeholder"), aResult);

   243 }

   245 void

   246 nsPlaceholderFrame::List(FILE* out, const char* aPrefix, uint32_t aFlags) const

   247 {

   248   nsCString str;

   249   ListGeneric(str, aPrefix, aFlags);

   251   if (mOutOfFlowFrame) {

   252     str += " outOfFlowFrame=";

   253     nsFrame::ListTag(str, mOutOfFlowFrame);

   254   }

   255   fprintf_stderr(out, "%s\n", str.get());

   256 }

   257 #endif

The Tor Browser / file revision

layout/generic/nsPlaceholderFrame.cpp@b8a032363ba2

layout/generic/nsPlaceholderFrame.cpp