third_party/WebKit/Source/core/layout/LayoutFlexibleBox.h

   1 /*
   2  * Copyright (C) 2011 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #ifndef LayoutFlexibleBox_h
  32 #define LayoutFlexibleBox_h
  33
  34 #include "core/CoreExport.h"
  35 #include "core/layout/LayoutBlock.h"
  36 #include "core/layout/OrderIterator.h"
  37
  38 namespace blink {
  39
  40 class CORE_EXPORT LayoutFlexibleBox : public LayoutBlock {
  41 public:
  42     LayoutFlexibleBox(Element*);
  43     ~LayoutFlexibleBox() override;
  44
  45     static LayoutFlexibleBox* createAnonymous(Document*);
  46
  47     const char* name() const override { return "LayoutFlexibleBox"; }
  48
  49     bool isFlexibleBox() const final { return true; }
  50     bool canCollapseAnonymousBlockChild() const override { return false; }
  51     void layoutBlock(bool relayoutChildren) final;
  52
  53     int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const override;
  54     int firstLineBoxBaseline() const override;
  55     int inlineBlockBaseline(LineDirectionMode) const override;
  56
  57     void paintChildren(const PaintInfo&, const LayoutPoint&) final;
  58
  59     bool isHorizontalFlow() const;
  60
  61     OrderIterator& orderIterator() { return m_orderIterator; }
  62
  63 protected:
  64     void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const override;
  65
  66     void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
  67     void removeChild(LayoutObject*) override;
  68
  69 private:
  70     enum FlexSign {
  71         PositiveFlexibility,
  72         NegativeFlexibility,
  73     };
  74
  75     enum PositionedLayoutMode {
  76         FlipForRowReverse,
  77         NoFlipForRowReverse,
  78     };
  79
  80     enum ChildLayoutType {
  81         LayoutIfNeeded,
  82         ForceLayout,
  83         NeverLayout
  84     };
  85
  86     typedef HashMap<const LayoutBox*, LayoutUnit> InflexibleFlexItemSize;
  87     typedef Vector<LayoutBox*> OrderedFlexItemList;
  88
  89     struct LineContext;
  90     struct Violation;
  91
  92     // Use an inline capacity of 8, since flexbox containers usually have less than 8 children.
  93     typedef Vector<LayoutRect, 8> ChildFrameRects;
  94
  95     bool hasOrthogonalFlow(LayoutBox& child) const;
  96     bool isColumnFlow() const;
  97     bool isLeftToRightFlow() const;
  98     bool isMultiline() const;
  99     Length flexBasisForChild(const LayoutBox& child) const;
 100     LayoutUnit crossAxisExtentForChild(LayoutBox& child) const;
 101     LayoutUnit crossAxisIntrinsicExtentForChild(LayoutBox& child) const;
 102     LayoutUnit childIntrinsicHeight(LayoutBox& child) const;
 103     LayoutUnit childIntrinsicWidth(LayoutBox& child) const;
 104     LayoutUnit mainAxisExtentForChild(LayoutBox& child) const;
 105     LayoutUnit crossAxisExtent() const;
 106     LayoutUnit mainAxisExtent() const;
 107     LayoutUnit crossAxisContentExtent() const;
 108     LayoutUnit mainAxisContentExtent(LayoutUnit contentLogicalHeight);
 109     LayoutUnit computeMainAxisExtentForChild(LayoutBox& child, SizeType, const Length& size);
 110     WritingMode transformedWritingMode() const;
 111     LayoutUnit flowAwareBorderStart() const;
 112     LayoutUnit flowAwareBorderEnd() const;
 113     LayoutUnit flowAwareBorderBefore() const;
 114     LayoutUnit flowAwareBorderAfter() const;
 115     LayoutUnit flowAwarePaddingStart() const;
 116     LayoutUnit flowAwarePaddingEnd() const;
 117     LayoutUnit flowAwarePaddingBefore() const;
 118     LayoutUnit flowAwarePaddingAfter() const;
 119     LayoutUnit flowAwareMarginStartForChild(LayoutBox& child) const;
 120     LayoutUnit flowAwareMarginEndForChild(LayoutBox& child) const;
 121     LayoutUnit flowAwareMarginBeforeForChild(LayoutBox& child) const;
 122     LayoutUnit crossAxisMarginExtentForChild(LayoutBox& child) const;
 123     LayoutUnit crossAxisScrollbarExtent() const;
 124     LayoutUnit crossAxisScrollbarExtentForChild(LayoutBox& child) const;
 125     LayoutPoint flowAwareLocationForChild(LayoutBox& child) const;
 126     // FIXME: Supporting layout deltas.
 127     void setFlowAwareLocationForChild(LayoutBox& child, const LayoutPoint&);
 128     void adjustAlignmentForChild(LayoutBox& child, LayoutUnit);
 129     ItemPosition alignmentForChild(LayoutBox& child) const;
 130     LayoutUnit mainAxisBorderAndPaddingExtentForChild(LayoutBox& child) const;
 131     LayoutUnit computeInnerFlexBaseSizeForChild(LayoutBox& child, ChildLayoutType = LayoutIfNeeded);
 132     bool mainAxisLengthIsDefinite(LayoutBox& child, const Length& flexBasis) const;
 133     bool childFlexBaseSizeRequiresLayout(LayoutBox& child) const;
 134     bool needToStretchChildLogicalHeight(LayoutBox& child) const;
 135     bool childHasIntrinsicMainAxisSize(const LayoutBox& child) const;
 136     EOverflow mainAxisOverflowForChild(LayoutBox& child) const;
 137     EOverflow crossAxisOverflowForChild(LayoutBox& child) const;
 138
 139     void layoutFlexItems(bool relayoutChildren, SubtreeLayoutScope&);
 140     LayoutUnit autoMarginOffsetInMainAxis(const OrderedFlexItemList&, LayoutUnit& availableFreeSpace);
 141     void updateAutoMarginsInMainAxis(LayoutBox& child, LayoutUnit autoMarginOffset);
 142     bool hasAutoMarginsInCrossAxis(LayoutBox& child) const;
 143     bool updateAutoMarginsInCrossAxis(LayoutBox& child, LayoutUnit availableAlignmentSpace);
 144     void repositionLogicalHeightDependentFlexItems(Vector<LineContext>&);
 145     LayoutUnit clientLogicalBottomAfterRepositioning();
 146
 147     LayoutUnit availableAlignmentSpaceForChild(LayoutUnit lineCrossAxisExtent, LayoutBox& child);
 148     LayoutUnit availableAlignmentSpaceForChildBeforeStretching(LayoutUnit lineCrossAxisExtent, LayoutBox& child);
 149     LayoutUnit marginBoxAscentForChild(LayoutBox& child);
 150
 151     LayoutUnit computeChildMarginValue(Length margin);
 152     void prepareOrderIteratorAndMargins();
 153     LayoutUnit adjustChildSizeForMinAndMax(LayoutBox& child, LayoutUnit childSize, bool childShrunk = false);
 154     // The hypothetical main size of an item is the flex base size clamped according to its min and max main size properties
 155     bool computeNextFlexLine(OrderedFlexItemList& orderedChildren, LayoutUnit& sumFlexBaseSize, double& totalFlexGrow, double& totalWeightedFlexShrink, LayoutUnit& sumHypotheticalMainSize, bool relayoutChildren);
 156
 157     bool resolveFlexibleLengths(FlexSign, const OrderedFlexItemList&, LayoutUnit& availableFreeSpace, double& totalFlexGrow, double& totalWeightedFlexShrink, InflexibleFlexItemSize&, Vector<LayoutUnit, 16>& childSizes);
 158     void freezeViolations(const Vector<Violation>&, LayoutUnit& availableFreeSpace, double& totalFlexGrow, double& totalWeightedFlexShrink, InflexibleFlexItemSize&);
 159
 160     void resetAutoMarginsAndLogicalTopInCrossAxis(LayoutBox& child);
 161     void setOverrideMainAxisSizeForChild(LayoutBox& child, LayoutUnit childPreferredSize);
 162     void prepareChildForPositionedLayout(LayoutBox& child, LayoutUnit mainAxisOffset, LayoutUnit crossAxisOffset, PositionedLayoutMode);
 163     size_t numberOfInFlowPositionedChildren(const OrderedFlexItemList&) const;
 164     void layoutAndPlaceChildren(LayoutUnit& crossAxisOffset, const OrderedFlexItemList&, const Vector<LayoutUnit, 16>& childSizes, LayoutUnit availableFreeSpace, bool relayoutChildren, SubtreeLayoutScope&, Vector<LineContext>&);
 165     void layoutColumnReverse(const OrderedFlexItemList&, LayoutUnit crossAxisOffset, LayoutUnit availableFreeSpace);
 166     void alignFlexLines(Vector<LineContext>&);
 167     void alignChildren(const Vector<LineContext>&);
 168     void applyStretchAlignmentToChild(LayoutBox& child, LayoutUnit lineCrossAxisExtent);
 169     void flipForRightToLeftColumn();
 170     void flipForWrapReverse(const Vector<LineContext>&, LayoutUnit crossAxisStartEdge);
 171
 172     float countIntrinsicSizeForAlgorithmChange(LayoutUnit maxPreferredWidth, LayoutBox* child, float previousMaxContentFlexFraction) const;
 173
 174     // This is used to cache the preferred size for orthogonal flow children so we don't have to relayout to get it
 175     HashMap<const LayoutObject*, LayoutUnit> m_intrinsicSizeAlongMainAxis;
 176
 177     mutable OrderIterator m_orderIterator;
 178     int m_numberOfInFlowChildrenOnFirstLine;
 179 };
 180
 181 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutFlexibleBox, isFlexibleBox());
 182
 183 } // namespace blink
 184
 185 #endif // LayoutFlexibleBox_h