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  * 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.

    12  *

    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 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. 

    24  */

    25 

    26 #include "config.h"

    27 #include "RenderScrollbarPart.h"

    28 #include "RenderScrollbar.h"

    29 #include "RenderScrollbarTheme.h"

    30 #include "RenderView.h"

    31 

    32 using namespace std;

    33 

    34 namespace WebCore {

    35 

    36 RenderScrollbarPart::RenderScrollbarPart(Node* node, RenderScrollbar* scrollbar, ScrollbarPart part)

    37     : RenderBlock(node)

    38     , m_scrollbar(scrollbar)

    39     , m_part(part)

    40 {

    41 }

    42 

    43 RenderScrollbarPart::~RenderScrollbarPart()

    44 {

    45 }

    46 

    47 void RenderScrollbarPart::layout()

    48 {

    49     setLocation(IntPoint()); // We don't worry about positioning ourselves.  We're just determining our minimum width/height.

    50     if (m_scrollbar->orientation() == HorizontalScrollbar)

    51         layoutHorizontalPart();

    52     else

    53         layoutVerticalPart();

    54 

    55     setNeedsLayout(false);

    56 }

    57 

    58 void RenderScrollbarPart::layoutHorizontalPart()

    59 {

    60     if (m_part == ScrollbarBGPart) {

    61         setWidth(m_scrollbar->width());

    62         computeScrollbarHeight();

    63     } else {

    64         computeScrollbarWidth();

    65         setHeight(m_scrollbar->height());

    66     }

    67 }

    68 

    69 void RenderScrollbarPart::layoutVerticalPart()

    70 {

    71     if (m_part == ScrollbarBGPart) {

    72         computeScrollbarWidth();

    73         setHeight(m_scrollbar->height());

    74     } else {

    75         setWidth(m_scrollbar->width());

    76         computeScrollbarHeight();

    77     } 

    78 }

    79 

    80 static int calcScrollbarThicknessUsing(const Length& l, int containingLength)

    81 {

    82     if (l.isIntrinsicOrAuto())

    83         return ScrollbarTheme::nativeTheme()->scrollbarThickness();

    84     return l.calcMinValue(containingLength);

    85 }

    86 

    87 void RenderScrollbarPart::computeScrollbarWidth()

    88 {

    89     int visibleSize = m_scrollbar->owningRenderer()->width() - m_scrollbar->owningRenderer()->borderLeft() - m_scrollbar->owningRenderer()->borderRight();

    90     int w = calcScrollbarThicknessUsing(style()->width(), visibleSize);

    91     int minWidth = calcScrollbarThicknessUsing(style()->minWidth(), visibleSize);

    92     int maxWidth = style()->maxWidth().isUndefined() ? w : calcScrollbarThicknessUsing(style()->maxWidth(), visibleSize);

    93     setWidth(max(minWidth, min(maxWidth, w)));

    94     

    95     // Buttons and track pieces can all have margins along the axis of the scrollbar. 

    96     m_marginLeft = style()->marginLeft().calcMinValue(visibleSize);

    97     m_marginRight = style()->marginRight().calcMinValue(visibleSize);

    98 }

    99 

   100 void RenderScrollbarPart::computeScrollbarHeight()

   101 {

   102     int visibleSize = m_scrollbar->owningRenderer()->height() -  m_scrollbar->owningRenderer()->borderTop() - m_scrollbar->owningRenderer()->borderBottom();

   103     int h = calcScrollbarThicknessUsing(style()->height(), visibleSize);

   104     int minHeight = calcScrollbarThicknessUsing(style()->minHeight(), visibleSize);

   105     int maxHeight = style()->maxHeight().isUndefined() ? h : calcScrollbarThicknessUsing(style()->maxHeight(), visibleSize);

   106     setHeight(max(minHeight, min(maxHeight, h)));

   107 

   108     // Buttons and track pieces can all have margins along the axis of the scrollbar. 

   109     m_marginTop = style()->marginTop().calcMinValue(visibleSize);

   110     m_marginBottom = style()->marginBottom().calcMinValue(visibleSize);

   111 }

   112 

   113 void RenderScrollbarPart::calcPrefWidths()

   114 {

   115     if (!prefWidthsDirty())

   116         return;

   117     

   118     m_minPrefWidth = m_maxPrefWidth = 0;

   119 

   120     setPrefWidthsDirty(false);

   121 }

   122 

   123 void RenderScrollbarPart::styleWillChange(StyleDifference diff, const RenderStyle* newStyle)

   124 {

   125     RenderBlock::styleWillChange(diff, newStyle);

   126     setInline(false);

   127 }

   128 

   129 void RenderScrollbarPart::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)

   130 {

   131     RenderBlock::styleDidChange(diff, oldStyle);

   132     setInline(false);

   133     setPositioned(false);

   134     setFloating(false);

   135     setHasOverflowClip(false);

   136     if (oldStyle && m_scrollbar && m_part != NoPart && diff >= StyleDifferenceRepaint)

   137         m_scrollbar->theme()->invalidatePart(m_scrollbar, m_part);

   138 }

   139 

   140 void RenderScrollbarPart::imageChanged(WrappedImagePtr image, const IntRect* rect)

   141 {

   142     if (m_scrollbar && m_part != NoPart)

   143         m_scrollbar->theme()->invalidatePart(m_scrollbar, m_part);

   144     else {

   145         if (FrameView* frameView = view()->frameView()) {

   146             if (frameView->isFrameViewScrollCorner(this)) {

   147                 frameView->invalidateScrollCorner();

   148                 return;

   149             }

   150         }

   151         

   152         RenderBlock::imageChanged(image, rect);

   153     }

   154 }

   155 

   156 void RenderScrollbarPart::paintIntoRect(GraphicsContext* graphicsContext, int tx, int ty, const IntRect& rect)

   157 {

   158     // Make sure our dimensions match the rect.

   159     setLocation(rect.x() - tx, rect.y() - ty);

   160     setWidth(rect.width());

   161     setHeight(rect.height());

   162 

   163     if (graphicsContext->paintingDisabled())

   164         return;

   165 

   166     // Now do the paint.

   167     PaintInfo paintInfo(graphicsContext, rect, PaintPhaseBlockBackground, false, 0, 0);

   168     paint(paintInfo, tx, ty);

   169     paintInfo.phase = PaintPhaseChildBlockBackgrounds;

   170     paint(paintInfo, tx, ty);

   171     paintInfo.phase = PaintPhaseFloat;

   172     paint(paintInfo, tx, ty);

   173     paintInfo.phase = PaintPhaseForeground;

   174     paint(paintInfo, tx, ty);

   175     paintInfo.phase = PaintPhaseOutline;

   176     paint(paintInfo, tx, ty);

   177 }

   178 

   179 }