mirror of
https://github.com/flutter/flutter.git
synced 2026-02-20 02:29:02 +08:00
d7daaf4c7d
We use pointer events now. R=esprehn@chromium.org Review URL: https://codereview.chromium.org/870073003
101 lines
3.4 KiB
C++
101 lines
3.4 KiB
C++
/*
|
|
* Copyright (c) 2010, Google Inc. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are
|
|
* met:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above
|
|
* copyright notice, this list of conditions and the following disclaimer
|
|
* in the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* * Neither the name of Google Inc. nor the names of its
|
|
* contributors may be used to endorse or promote products derived from
|
|
* this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include "sky/engine/config.h"
|
|
#include "sky/engine/platform/scroll/ScrollAnimator.h"
|
|
|
|
#include <algorithm>
|
|
#include "sky/engine/platform/geometry/FloatPoint.h"
|
|
#include "sky/engine/platform/scroll/ScrollableArea.h"
|
|
#include "sky/engine/wtf/PassOwnPtr.h"
|
|
|
|
namespace blink {
|
|
|
|
ScrollAnimator::ScrollAnimator(ScrollableArea* scrollableArea)
|
|
: m_scrollableArea(scrollableArea)
|
|
, m_currentPosX(0)
|
|
, m_currentPosY(0)
|
|
{
|
|
}
|
|
|
|
ScrollAnimator::~ScrollAnimator()
|
|
{
|
|
}
|
|
|
|
PassOwnPtr<ScrollAnimator> ScrollAnimator::create(ScrollableArea* scrollableArea)
|
|
{
|
|
return adoptPtr(new ScrollAnimator(scrollableArea));
|
|
}
|
|
|
|
bool ScrollAnimator::scroll(ScrollbarOrientation orientation, ScrollGranularity, float step, float delta)
|
|
{
|
|
float& currentPos = (orientation == HorizontalScrollbar) ? m_currentPosX : m_currentPosY;
|
|
float newPos = clampScrollPosition(orientation, currentPos + step * delta);
|
|
if (currentPos == newPos)
|
|
return false;
|
|
currentPos = newPos;
|
|
|
|
notifyPositionChanged();
|
|
|
|
return true;
|
|
}
|
|
|
|
void ScrollAnimator::scrollToOffsetWithoutAnimation(const FloatPoint& offset)
|
|
{
|
|
m_currentPosX = offset.x();
|
|
m_currentPosY = offset.y();
|
|
notifyPositionChanged();
|
|
}
|
|
|
|
void ScrollAnimator::setCurrentPosition(const FloatPoint& position)
|
|
{
|
|
m_currentPosX = position.x();
|
|
m_currentPosY = position.y();
|
|
}
|
|
|
|
FloatPoint ScrollAnimator::currentPosition() const
|
|
{
|
|
return FloatPoint(m_currentPosX, m_currentPosY);
|
|
}
|
|
|
|
void ScrollAnimator::notifyPositionChanged()
|
|
{
|
|
m_scrollableArea->setScrollOffsetFromAnimation(IntPoint(m_currentPosX, m_currentPosY));
|
|
}
|
|
|
|
float ScrollAnimator::clampScrollPosition(ScrollbarOrientation orientation, float pos)
|
|
{
|
|
float maxScrollPos = m_scrollableArea->maximumScrollPosition(orientation);
|
|
float minScrollPos = m_scrollableArea->minimumScrollPosition(orientation);
|
|
return std::max(std::min(pos, maxScrollPos), minScrollPos);
|
|
}
|
|
|
|
} // namespace blink
|