1 /* 2 * Copyright (c) 2010, Google 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 are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef ScrollAnimator_h 32 #define ScrollAnimator_h 33 34 #include "platform/PlatformExport.h" 35 #include "platform/PlatformWheelEvent.h" 36 #include "platform/geometry/FloatSize.h" 37 #include "platform/scroll/ScrollTypes.h" 38 #include "wtf/FastAllocBase.h" 39 #include "wtf/Forward.h" 40 #include "wtf/Noncopyable.h" 41 42 namespace WebCore { 43 44 class FloatPoint; 45 class ScrollableArea; 46 class Scrollbar; 47 48 class PLATFORM_EXPORT ScrollAnimator { 49 WTF_MAKE_FAST_ALLOCATED; WTF_MAKE_NONCOPYABLE(ScrollAnimator); 50 public: 51 static PassOwnPtr<ScrollAnimator> create(ScrollableArea*); 52 53 virtual ~ScrollAnimator(); 54 55 // Computes a scroll destination for the given parameters. Returns false if 56 // already at the destination. Otherwise, starts scrolling towards the 57 // destination and returns true. Scrolling may be immediate or animated. 58 // The base class implementation always scrolls immediately, never animates. 59 virtual bool scroll(ScrollbarOrientation, ScrollGranularity, float step, float delta); 60 61 virtual void scrollToOffsetWithoutAnimation(const FloatPoint&); 62 scrollableArea()63 ScrollableArea* scrollableArea() const { return m_scrollableArea; } 64 setIsActive()65 virtual void setIsActive() { } 66 67 virtual bool handleWheelEvent(const PlatformWheelEvent&); 68 69 #if OS(MACOSX) handleWheelEventPhase(PlatformWheelEventPhase)70 virtual void handleWheelEventPhase(PlatformWheelEventPhase) { } 71 #endif 72 73 void setCurrentPosition(const FloatPoint&); 74 FloatPoint currentPosition() const; 75 cancelAnimations()76 virtual void cancelAnimations() { } serviceScrollAnimations()77 virtual void serviceScrollAnimations() { } 78 contentAreaWillPaint()79 virtual void contentAreaWillPaint() const { } mouseEnteredContentArea()80 virtual void mouseEnteredContentArea() const { } mouseExitedContentArea()81 virtual void mouseExitedContentArea() const { } mouseMovedInContentArea()82 virtual void mouseMovedInContentArea() const { } mouseEnteredScrollbar(Scrollbar *)83 virtual void mouseEnteredScrollbar(Scrollbar*) const { } mouseExitedScrollbar(Scrollbar *)84 virtual void mouseExitedScrollbar(Scrollbar*) const { } willStartLiveResize()85 virtual void willStartLiveResize() { } contentsResized()86 virtual void contentsResized() const { } willEndLiveResize()87 virtual void willEndLiveResize() { } contentAreaDidShow()88 virtual void contentAreaDidShow() const { } contentAreaDidHide()89 virtual void contentAreaDidHide() const { } 90 finishCurrentScrollAnimations()91 virtual void finishCurrentScrollAnimations() { } 92 didAddVerticalScrollbar(Scrollbar *)93 virtual void didAddVerticalScrollbar(Scrollbar*) { } willRemoveVerticalScrollbar(Scrollbar *)94 virtual void willRemoveVerticalScrollbar(Scrollbar*) { } didAddHorizontalScrollbar(Scrollbar *)95 virtual void didAddHorizontalScrollbar(Scrollbar*) { } willRemoveHorizontalScrollbar(Scrollbar *)96 virtual void willRemoveHorizontalScrollbar(Scrollbar*) { } 97 shouldScrollbarParticipateInHitTesting(Scrollbar *)98 virtual bool shouldScrollbarParticipateInHitTesting(Scrollbar*) { return true; } 99 notifyContentAreaScrolled(const FloatSize &)100 virtual void notifyContentAreaScrolled(const FloatSize&) { } 101 isRubberBandInProgress()102 virtual bool isRubberBandInProgress() const { return false; } 103 104 protected: 105 explicit ScrollAnimator(ScrollableArea*); 106 107 virtual void notifyPositionChanged(); 108 109 ScrollableArea* m_scrollableArea; 110 float m_currentPosX; // We avoid using a FloatPoint in order to reduce 111 float m_currentPosY; // subclass code complexity. 112 113 private: 114 float clampScrollPosition(ScrollbarOrientation, float); 115 }; 116 117 } // namespace WebCore 118 119 #endif // ScrollAnimator_h 120