third_party/WebKit/Source/core/layout/LayoutSliderContainer.cpp

   1 /*
   2  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
   3  * Copyright (C) 2010 Google Inc. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met:
   8  *
   9  *     * Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  *     * Redistributions in binary form must reproduce the above
  12  * copyright notice, this list of conditions and the following disclaimer
  13  * in the documentation and/or other materials provided with the
  14  * distribution.
  15  *     * Neither the name of Google Inc. nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include "config.h"
  33 #include "core/layout/LayoutSliderContainer.h"
  34
  35 #include "core/dom/shadow/ShadowRoot.h"
  36 #include "core/html/HTMLInputElement.h"
  37 #include "core/html/parser/HTMLParserIdioms.h"
  38 #include "core/html/shadow/ShadowElementNames.h"
  39 #include "core/html/shadow/SliderThumbElement.h"
  40 #include "core/layout/LayoutFlexibleBox.h"
  41 #include "core/layout/LayoutSlider.h"
  42 #include "core/layout/LayoutTheme.h"
  43
  44 namespace blink {
  45
  46 LayoutSliderContainer::LayoutSliderContainer(SliderContainerElement* element)
  47     : LayoutFlexibleBox(element)
  48 {
  49 }
  50
  51 inline static Decimal sliderPosition(HTMLInputElement* element)
  52 {
  53     const StepRange stepRange(element->createStepRange(RejectAny));
  54     const Decimal oldValue = parseToDecimalForNumberType(element->value(), stepRange.defaultValue());
  55     return stepRange.proportionFromValue(stepRange.clampValue(oldValue));
  56 }
  57
  58 inline static bool hasVerticalAppearance(HTMLInputElement* input)
  59 {
  60     ASSERT(input->layoutObject());
  61     const ComputedStyle& sliderStyle = input->layoutObject()->styleRef();
  62
  63     return sliderStyle.appearance() == SliderVerticalPart;
  64 }
  65
  66 void LayoutSliderContainer::computeLogicalHeight(LayoutUnit logicalHeight, LayoutUnit logicalTop, LogicalExtentComputedValues& computedValues) const
  67 {
  68     HTMLInputElement* input = toHTMLInputElement(node()->shadowHost());
  69     bool isVertical = hasVerticalAppearance(input);
  70
  71     if (input->layoutObject()->isSlider() && !isVertical && input->list()) {
  72         int offsetFromCenter = LayoutTheme::theme().sliderTickOffsetFromTrackCenter();
  73         LayoutUnit trackHeight = 0;
  74         if (offsetFromCenter < 0) {
  75             trackHeight = -2 * offsetFromCenter;
  76         } else {
  77             int tickLength = LayoutTheme::theme().sliderTickSize().height();
  78             trackHeight = 2 * (offsetFromCenter + tickLength);
  79         }
  80         float zoomFactor = style()->effectiveZoom();
  81         if (zoomFactor != 1.0)
  82             trackHeight *= zoomFactor;
  83
  84         // FIXME: The trackHeight should have been added before updateLogicalHeight was called to avoid this hack.
  85         setIntrinsicContentLogicalHeight(trackHeight);
  86
  87         LayoutBox::computeLogicalHeight(trackHeight, logicalTop, computedValues);
  88         return;
  89     }
  90     if (isVertical)
  91         logicalHeight = LayoutSlider::defaultTrackLength;
  92
  93     // FIXME: The trackHeight should have been added before updateLogicalHeight was called to avoid this hack.
  94     setIntrinsicContentLogicalHeight(logicalHeight);
  95
  96     LayoutBox::computeLogicalHeight(logicalHeight, logicalTop, computedValues);
  97 }
  98
  99 void LayoutSliderContainer::layout()
 100 {
 101     HTMLInputElement* input = toHTMLInputElement(node()->shadowHost());
 102     bool isVertical = hasVerticalAppearance(input);
 103     mutableStyleRef().setFlexDirection(isVertical ? FlowColumn : FlowRow);
 104     TextDirection oldTextDirection = style()->direction();
 105     if (isVertical) {
 106         // FIXME: Work around rounding issues in RTL vertical sliders. We want them to
 107         // render identically to LTR vertical sliders. We can remove this work around when
 108         // subpixel rendering is enabled on all ports.
 109         mutableStyleRef().setDirection(LTR);
 110     }
 111
 112     Element* thumbElement = input->userAgentShadowRoot()->getElementById(ShadowElementNames::sliderThumb());
 113     Element* trackElement = input->userAgentShadowRoot()->getElementById(ShadowElementNames::sliderTrack());
 114     LayoutBox* thumb = thumbElement ? thumbElement->layoutBox() : 0;
 115     LayoutBox* track = trackElement ? trackElement->layoutBox() : 0;
 116
 117     SubtreeLayoutScope layoutScope(*this);
 118     // Force a layout to reset the position of the thumb so the code below doesn't move the thumb to the wrong place.
 119     // FIXME: Make a custom layout class for the track and move the thumb positioning code there.
 120     if (track)
 121         layoutScope.setChildNeedsLayout(track);
 122
 123     LayoutFlexibleBox::layout();
 124
 125     mutableStyleRef().setDirection(oldTextDirection);
 126     // These should always exist, unless someone mutates the shadow DOM (e.g., in the inspector).
 127     if (!thumb || !track)
 128         return;
 129
 130     double percentageOffset = sliderPosition(input).toDouble();
 131     LayoutUnit availableExtent = isVertical ? track->contentHeight() : track->contentWidth();
 132     availableExtent -= isVertical ? thumb->size().height() : thumb->size().width();
 133     LayoutUnit offset = percentageOffset * availableExtent;
 134     LayoutPoint thumbLocation = thumb->location();
 135     if (isVertical)
 136         thumbLocation.setY(thumbLocation.y() + track->contentHeight() - thumb->size().height() - offset);
 137     else if (style()->isLeftToRightDirection())
 138         thumbLocation.setX(thumbLocation.x() + offset);
 139     else
 140         thumbLocation.setX(thumbLocation.x() - offset);
 141     thumb->setLocation(thumbLocation);
 142
 143     // We need one-off invalidation code here because painting of the timeline element does not go through style.
 144     // Instead it has a custom implementation in C++ code.
 145     // Therefore the style system cannot understand when it needs to be paint invalidated.
 146     setShouldDoFullPaintInvalidation();
 147 }
 148
 149 } // namespace blink