2 * Copyright (C) 2012 Apple Inc. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #ifndef RenderMultiColumnBlock_h
28 #define RenderMultiColumnBlock_h
30 #include "core/rendering/RenderBlockFlow.h"
34 class RenderMultiColumnFlowThread;
36 class RenderMultiColumnBlock FINAL : public RenderBlockFlow {
38 RenderMultiColumnBlock(Element*);
40 LayoutUnit columnHeightAvailable() const { return m_columnHeightAvailable; }
42 LayoutUnit columnWidth() const { return m_columnWidth; }
43 unsigned columnCount() const { return m_columnCount; }
45 RenderMultiColumnFlowThread* flowThread() const { return m_flowThread; }
47 bool requiresBalancing() const { return !m_columnHeightAvailable || style()->columnFill() == ColumnFillBalance; }
49 bool shouldRelayoutMultiColumnBlock();
52 virtual bool isRenderMultiColumnBlock() const OVERRIDE { return true; }
54 virtual const char* renderName() const OVERRIDE;
56 virtual RenderObject* layoutSpecialExcludedChild(bool relayoutChildren, SubtreeLayoutScope&) OVERRIDE;
58 virtual void styleDidChange(StyleDifference, const RenderStyle*) OVERRIDE;
60 virtual bool updateLogicalWidthAndColumnWidth() OVERRIDE;
61 virtual void checkForPaginationLogicalHeightChange(LayoutUnit&, bool&, bool&) OVERRIDE;
63 virtual bool supportsPartialLayout() const OVERRIDE { return false; }
65 virtual void addChild(RenderObject* newChild, RenderObject* beforeChild = 0) OVERRIDE;
67 void computeColumnCountAndWidth();
69 void ensureColumnSets();
71 RenderMultiColumnFlowThread* m_flowThread;
72 unsigned m_columnCount; // The default column count/width that are based off our containing block width. These values represent only the default,
73 LayoutUnit m_columnWidth; // since a multi-column block that is split across variable width pages or regions will have different column counts and widths in each.
74 // These values will be cached (eventually) for multi-column blocks.
75 LayoutUnit m_columnHeightAvailable; // Total height available to columns, or 0 if auto.
76 bool m_inBalancingPass; // Set when relayouting for column balancing.
77 bool m_needsRebalancing;
80 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderMultiColumnBlock, isRenderMultiColumnBlock());
82 } // namespace WebCore
84 #endif // RenderMultiColumnBlock_h