Source/core/page/scrolling/ScrollCustomizationCallbacks.h

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef ScrollCustomizationCallbacks_h
#define ScrollCustomizationCallbacks_h

#include "core/CoreExport.h"
#include "core/dom/Element.h"
#include "platform/heap/Handle.h"
#include "wtf/HashMap.h"

namespace blink {

class ScrollStateCallback;

class CORE_EXPORT ScrollCustomizationCallbacks : public GarbageCollected<ScrollCustomizationCallbacks> {
    WTF_MAKE_NONCOPYABLE(ScrollCustomizationCallbacks);

public:
    ScrollCustomizationCallbacks() {}
    void setDistributeScroll(Element*, ScrollStateCallback*);
    ScrollStateCallback* getDistributeScroll(Element*);
    void setApplyScroll(Element*, ScrollStateCallback*);
    ScrollStateCallback* getApplyScroll(Element*);

    DEFINE_INLINE_TRACE()
    {
        visitor->trace(m_applyScrollCallbacks);
        visitor->trace(m_distributeScrollCallbacks);
    };

#if !ENABLE(OILPAN)
    void removeCallbacksForElement(Element*);
#endif

private:
    using ScrollStateCallbackList = HeapHashMap<RawPtrWillBeWeakMember<Element>, Member<ScrollStateCallback>>;
    ScrollStateCallbackList m_applyScrollCallbacks;
    ScrollStateCallbackList m_distributeScrollCallbacks;
};

} // namespace blink

#endif // ScrollCustomizationCallbacks_h