summaryrefslogtreecommitdiff
path: root/layout/generic/nsPlaceholderFrame.cpp
blob: f8678dcbdfd565aef259dfc867cf99b26871cdaa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
/* -*- 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/. */

/*
 * rendering object for the point that anchors out-of-flow rendering
 * objects such as floats and absolutely positioned elements
 */

#include "nsPlaceholderFrame.h"

#include "gfxUtils.h"
#include "mozilla/gfx/2D.h"
#include "nsDisplayList.h"
#include "nsFrameManager.h"
#include "nsLayoutUtils.h"
#include "nsPresContext.h"
#include "nsRenderingContext.h"
#include "nsIFrameInlines.h"
#include "nsIContentInlines.h"

using namespace mozilla;
using namespace mozilla::gfx;

nsIFrame*
NS_NewPlaceholderFrame(nsIPresShell* aPresShell, nsStyleContext* aContext,
                       nsFrameState aTypeBit)
{
  return new (aPresShell) nsPlaceholderFrame(aContext, aTypeBit);
}

NS_IMPL_FRAMEARENA_HELPERS(nsPlaceholderFrame)

#ifdef DEBUG
NS_QUERYFRAME_HEAD(nsPlaceholderFrame)
  NS_QUERYFRAME_ENTRY(nsPlaceholderFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsFrame)
#endif

/* virtual */ nsSize
nsPlaceholderFrame::GetXULMinSize(nsBoxLayoutState& aBoxLayoutState)
{
  nsSize size(0, 0);
  DISPLAY_MIN_SIZE(this, size);
  return size;
}

/* virtual */ nsSize
nsPlaceholderFrame::GetXULPrefSize(nsBoxLayoutState& aBoxLayoutState)
{
  nsSize size(0, 0);
  DISPLAY_PREF_SIZE(this, size);
  return size;
}

/* virtual */ nsSize
nsPlaceholderFrame::GetXULMaxSize(nsBoxLayoutState& aBoxLayoutState)
{
  nsSize size(NS_INTRINSICSIZE, NS_INTRINSICSIZE);
  DISPLAY_MAX_SIZE(this, size);
  return size;
}

/* virtual */ void
nsPlaceholderFrame::AddInlineMinISize(nsRenderingContext* aRenderingContext,
                                      nsIFrame::InlineMinISizeData* aData)
{
  // Override AddInlineMinWith so that *nothing* happens.  In
  // particular, we don't want to zero out |aData->mTrailingWhitespace|,
  // since nsLineLayout skips placeholders when trimming trailing
  // whitespace, and we don't want to set aData->mSkipWhitespace to
  // false.

  // ...but push floats onto the list
  if (mOutOfFlowFrame->IsFloating()) {
    nscoord floatWidth =
      nsLayoutUtils::IntrinsicForContainer(aRenderingContext,
                                           mOutOfFlowFrame,
                                           nsLayoutUtils::MIN_ISIZE);
    aData->mFloats.AppendElement(
      InlineIntrinsicISizeData::FloatInfo(mOutOfFlowFrame, floatWidth));
  }
}

/* virtual */ void
nsPlaceholderFrame::AddInlinePrefISize(nsRenderingContext* aRenderingContext,
                                       nsIFrame::InlinePrefISizeData* aData)
{
  // Override AddInlinePrefWith so that *nothing* happens.  In
  // particular, we don't want to zero out |aData->mTrailingWhitespace|,
  // since nsLineLayout skips placeholders when trimming trailing
  // whitespace, and we don't want to set aData->mSkipWhitespace to
  // false.

  // ...but push floats onto the list
  if (mOutOfFlowFrame->IsFloating()) {
    nscoord floatWidth =
      nsLayoutUtils::IntrinsicForContainer(aRenderingContext,
                                           mOutOfFlowFrame,
                                           nsLayoutUtils::PREF_ISIZE);
    aData->mFloats.AppendElement(
      InlineIntrinsicISizeData::FloatInfo(mOutOfFlowFrame, floatWidth));
  }
}

void
nsPlaceholderFrame::Reflow(nsPresContext*           aPresContext,
                           ReflowOutput&     aDesiredSize,
                           const ReflowInput& aReflowInput,
                           nsReflowStatus&          aStatus)
{
#ifdef DEBUG
  // We should be getting reflowed before our out-of-flow.
  // If this is our first reflow, and our out-of-flow has already received its
  // first reflow (before us), complain.
  // XXXdholbert This "look for a previous continuation or IB-split sibling"
  // code could use nsLayoutUtils::GetPrevContinuationOrIBSplitSibling(), if
  // we ever add a function like that. (We currently have a "Next" version.)
  if ((GetStateBits() & NS_FRAME_FIRST_REFLOW) &&
      !(mOutOfFlowFrame->GetStateBits() & NS_FRAME_FIRST_REFLOW)) {

    // Unfortunately, this can currently happen when the placeholder is in a
    // later continuation or later IB-split sibling than its out-of-flow (as
    // is the case in some of our existing unit tests). So for now, in that
    // case, we'll warn instead of asserting.
    bool isInContinuationOrIBSplit = false;
    nsIFrame* ancestor = this;
    while ((ancestor = ancestor->GetParent())) {
      if (ancestor->GetPrevContinuation() ||
          ancestor->GetProperty(IBSplitPrevSibling())) {
        isInContinuationOrIBSplit = true;
        break;
      }
    }

    if (isInContinuationOrIBSplit) {
      NS_WARNING("Out-of-flow frame got reflowed before its placeholder");
    } else {
      NS_ERROR("Out-of-flow frame got reflowed before its placeholder");
    }
  }
#endif

  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsPlaceholderFrame");
  DISPLAY_REFLOW(aPresContext, this, aReflowInput, aDesiredSize, aStatus);
  aDesiredSize.ClearSize();

  aStatus = NS_FRAME_COMPLETE;
  NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aDesiredSize);
}

void
nsPlaceholderFrame::DestroyFrom(nsIFrame* aDestructRoot)
{
  nsIFrame* oof = mOutOfFlowFrame;
  if (oof) {
    mOutOfFlowFrame = nullptr;
    oof->DeleteProperty(nsIFrame::PlaceholderFrameProperty());
    // If aDestructRoot is not an ancestor of the out-of-flow frame,
    // then call RemoveFrame on it here.
    // Also destroy it here if it's a popup frame. (Bug 96291)
    if ((GetStateBits() & PLACEHOLDER_FOR_POPUP) ||
        !nsLayoutUtils::IsProperAncestorFrame(aDestructRoot, oof)) {
      ChildListID listId = nsLayoutUtils::GetChildListNameFor(oof);
      nsFrameManager* fm = PresContext()->GetPresShell()->FrameManager();
      fm->RemoveFrame(listId, oof);
    }
    // else oof will be destroyed by its parent
  }

  nsFrame::DestroyFrom(aDestructRoot);
}

nsIAtom*
nsPlaceholderFrame::GetType() const
{
  return nsGkAtoms::placeholderFrame;
}

/* virtual */ bool
nsPlaceholderFrame::CanContinueTextRun() const
{
  if (!mOutOfFlowFrame) {
    return false;
  }
  // first-letter frames can continue text runs, and placeholders for floated
  // first-letter frames can too
  return mOutOfFlowFrame->CanContinueTextRun();
}

nsStyleContext*
nsPlaceholderFrame::GetParentStyleContext(nsIFrame** aProviderFrame) const
{
  NS_PRECONDITION(GetParent(), "How can we not have a parent here?");

  nsIContent* parentContent = mContent ? mContent->GetFlattenedTreeParent() : nullptr;
  if (parentContent) {
    nsStyleContext* sc =
      PresContext()->FrameManager()->GetDisplayContentsStyleFor(parentContent);
    if (sc) {
      *aProviderFrame = nullptr;
      return sc;
    }
  }

  // Lie about our pseudo so we can step out of all anon boxes and
  // pseudo-elements.  The other option would be to reimplement the
  // {ib} split gunk here.
  *aProviderFrame = CorrectStyleParentFrame(GetParent(), nsGkAtoms::placeholderFrame);
  return *aProviderFrame ? (*aProviderFrame)->StyleContext() : nullptr;
}


#ifdef DEBUG
static void
PaintDebugPlaceholder(nsIFrame* aFrame, DrawTarget* aDrawTarget,
                      const nsRect& aDirtyRect, nsPoint aPt)
{
  ColorPattern cyan(ToDeviceColor(Color(0.f, 1.f, 1.f, 1.f)));
  int32_t appUnitsPerDevPixel = aFrame->PresContext()->AppUnitsPerDevPixel();

  nscoord x = nsPresContext::CSSPixelsToAppUnits(-5);
  nsRect r(aPt.x + x, aPt.y,
           nsPresContext::CSSPixelsToAppUnits(13),
           nsPresContext::CSSPixelsToAppUnits(3));
  aDrawTarget->FillRect(NSRectToRect(r, appUnitsPerDevPixel), cyan);

  nscoord y = nsPresContext::CSSPixelsToAppUnits(-10);
  r = nsRect(aPt.x, aPt.y + y,
             nsPresContext::CSSPixelsToAppUnits(3),
             nsPresContext::CSSPixelsToAppUnits(10));
  aDrawTarget->FillRect(NSRectToRect(r, appUnitsPerDevPixel), cyan);
}
#endif // DEBUG

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

void
nsPlaceholderFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                     const nsDisplayListSet& aLists)
{
  DO_GLOBAL_REFLOW_COUNT_DSP("nsPlaceholderFrame");
  
#ifdef DEBUG
  if (GetShowFrameBorders()) {
    aLists.Outlines()->AppendNewToTop(
      new (aBuilder) nsDisplayGeneric(aBuilder, this, PaintDebugPlaceholder,
                                      "DebugPlaceholder",
                                      nsDisplayItem::TYPE_DEBUG_PLACEHOLDER));
  }
#endif
}
#endif // DEBUG || (MOZ_REFLOW_PERF_DSP && MOZ_REFLOW_PERF)

#ifdef DEBUG_FRAME_DUMP
nsresult
nsPlaceholderFrame::GetFrameName(nsAString& aResult) const
{
  return MakeFrameName(NS_LITERAL_STRING("Placeholder"), aResult);
}

void
nsPlaceholderFrame::List(FILE* out, const char* aPrefix, uint32_t aFlags) const
{
  nsCString str;
  ListGeneric(str, aPrefix, aFlags);

  if (mOutOfFlowFrame) {
    str += " outOfFlowFrame=";
    nsFrame::ListTag(str, mOutOfFlowFrame);
  }
  fprintf_stderr(out, "%s\n", str.get());
}
#endif