WebCore/accessibility/AccessibilityTableColumn.cpp

   1 /*
   2  * Copyright (C) 2008 Apple 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
   6  * are met:
   7  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  14  *     its contributors may be used to endorse or promote products derived
  15  *     from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "config.h"
  30 #include "AccessibilityTableColumn.h"
  31
  32 #include "AXObjectCache.h"
  33 #include "AccessibilityTableCell.h"
  34 #include "HTMLNames.h"
  35 #include "RenderTable.h"
  36 #include "RenderTableCell.h"
  37 #include "RenderTableSection.h"
  38
  39 using namespace std;
  40
  41 namespace WebCore {
  42
  43 using namespace HTMLNames;
  44
  45 AccessibilityTableColumn::AccessibilityTableColumn()
  46     : m_parentTable(0)
  47 {
  48 }
  49
  50 AccessibilityTableColumn::~AccessibilityTableColumn()
  51 {
  52 }
  53
  54 PassRefPtr<AccessibilityTableColumn> AccessibilityTableColumn::create()
  55 {
  56     return adoptRef(new AccessibilityTableColumn());
  57 }
  58
  59 void AccessibilityTableColumn::setParentTable(AccessibilityTable* table)
  60 {
  61     m_parentTable = table;
  62
  63     clearChildren();
  64 }
  65
  66 IntRect AccessibilityTableColumn::elementRect() const
  67 {
  68     // this will be filled in when addChildren is called
  69     return m_columnRect;
  70 }
  71
  72 IntSize AccessibilityTableColumn::size() const
  73 {
  74     return elementRect().size();
  75 }
  76
  77 const AccessibilityObject::AccessibilityChildrenVector& AccessibilityTableColumn::children()
  78 {
  79     if (!m_haveChildren)
  80         addChildren();
  81     return m_children;
  82 }
  83
  84 AccessibilityObject* AccessibilityTableColumn::headerObject()
  85 {
  86     if (!m_parentTable)
  87         return 0;
  88
  89     RenderObject* renderer = m_parentTable->renderer();
  90     if (!renderer)
  91         return 0;
  92
  93     if (m_parentTable->isAriaTable()) {
  94         AccessibilityChildrenVector rowChildren = children();
  95         unsigned childrenCount = rowChildren.size();
  96         for (unsigned i = 0; i < childrenCount; ++i) {
  97             AccessibilityObject* cell = rowChildren[i].get();
  98             if (cell->ariaRoleAttribute() == ColumnHeaderRole)
  99                 return cell;
 100         }
 101
 102         return 0;
 103     }
 104
 105     if (!renderer->isTable())
 106         return 0;
 107
 108     RenderTable* table = toRenderTable(renderer);
 109
 110     AccessibilityObject* headerObject = 0;
 111
 112     // try the <thead> section first. this doesn't require th tags
 113     headerObject = headerObjectForSection(table->header(), false);
 114
 115     if (headerObject)
 116         return headerObject;
 117
 118     // now try for <th> tags in the first body
 119     headerObject = headerObjectForSection(table->firstBody(), true);
 120
 121     return headerObject;
 122 }
 123
 124 AccessibilityObject* AccessibilityTableColumn::headerObjectForSection(RenderTableSection* section, bool thTagRequired)
 125 {
 126     if (!section)
 127         return 0;
 128
 129     int numCols = section->numColumns();
 130     if (m_columnIndex >= numCols)
 131         return 0;
 132
 133     RenderTableCell* cell = 0;
 134     // also account for cells that have a span
 135     for (int testCol = m_columnIndex; testCol >= 0; --testCol) {
 136         RenderTableCell* testCell = section->cellAt(0, testCol).cell;
 137         if (!testCell)
 138             continue;
 139
 140         // we've reached a cell that doesn't even overlap our column
 141         // it can't be our header
 142         if ((testCell->col() + (testCell->colSpan()-1)) < m_columnIndex)
 143             break;
 144
 145         Node* node = testCell->node();
 146         if (!node)
 147             continue;
 148
 149         if (thTagRequired && !node->hasTagName(thTag))
 150             continue;
 151
 152         cell = testCell;
 153     }
 154
 155     if (!cell)
 156         return 0;
 157
 158     return m_parentTable->axObjectCache()->getOrCreate(cell);
 159 }
 160
 161 void AccessibilityTableColumn::addChildren()
 162 {
 163     ASSERT(!m_haveChildren);
 164
 165     m_haveChildren = true;
 166     if (!m_parentTable)
 167         return;
 168
 169     int numRows = m_parentTable->rowCount();
 170
 171     for (int i = 0; i < numRows; i++) {
 172         AccessibilityTableCell* cell = m_parentTable->cellForColumnAndRow(m_columnIndex, i);
 173         if (!cell)
 174             continue;
 175
 176         // make sure the last one isn't the same as this one (rowspan cells)
 177         if (m_children.size() > 0 && m_children.last() == cell)
 178             continue;
 179
 180         m_children.append(cell);
 181         m_columnRect.unite(cell->elementRect());
 182     }
 183 }
 184
 185 } // namespace WebCore