Home | History | Annotate | Download | only in dom 
      1 /*
      2  * Copyright (C) 2013 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
      6  * are met:
      7  *  * Redistributions of source code must retain the above copyright
      8  *    notice, this list of conditions and the following disclaimer.
      9  *  * 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 THE COPYRIGHT HOLDERS ``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 THE COPYRIGHT OWNER 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 "core/dom/WheelController.h"
     28 
     29 #include "core/dom/Document.h"
     30 #include "core/events/ThreadLocalEventNames.h"
     31 #include "core/events/WheelEvent.h"
     32 #include "core/frame/Frame.h"
     33 #include "core/page/Page.h"
     34 #include "core/page/scrolling/ScrollingCoordinator.h"
     35 
     36 namespace WebCore {
     37 
     38 WheelController::WheelController(Document* document)
     39     : DOMWindowLifecycleObserver(document->domWindow())
     40     , m_wheelEventHandlerCount(0)
     41 {
     42 }
     43 
     44 WheelController::~WheelController()
     45 {
     46 }
     47 
     48 const char* WheelController::supplementName()
     49 {
     50     return "WheelController";
     51 }
     52 
     53 WheelController* WheelController::from(Document* document)
     54 {
     55     WheelController* controller = static_cast<WheelController*>(DocumentSupplement::from(document, supplementName()));
     56     if (!controller) {
     57         controller = new WheelController(document);
     58         DocumentSupplement::provideTo(document, supplementName(), adoptPtr(controller));
     59     }
     60     return controller;
     61 }
     62 
     63 static void wheelEventHandlerCountChanged(Document* document)
     64 {
     65     Page* page = document->page();
     66     if (!page)
     67         return;
     68 
     69     ScrollingCoordinator* scrollingCoordinator = page->scrollingCoordinator();
     70     if (!scrollingCoordinator)
     71         return;
     72 
     73     FrameView* frameView = document->view();
     74     if (!frameView)
     75         return;
     76 
     77     scrollingCoordinator->frameViewWheelEventHandlerCountChanged(frameView);
     78 }
     79 
     80 void WheelController::didAddWheelEventHandler(Document* document)
     81 {
     82     ++m_wheelEventHandlerCount;
     83     Page* page = document->page();
     84     Frame* mainFrame = page ? page->mainFrame() : 0;
     85     if (mainFrame)
     86         mainFrame->notifyChromeClientWheelEventHandlerCountChanged();
     87 
     88     wheelEventHandlerCountChanged(document);
     89 }
     90 
     91 void WheelController::didRemoveWheelEventHandler(Document* document)
     92 {
     93     ASSERT(m_wheelEventHandlerCount > 0);
     94     --m_wheelEventHandlerCount;
     95     Page* page = document->page();
     96     Frame* mainFrame = page ? page->mainFrame() : 0;
     97     if (mainFrame)
     98         mainFrame->notifyChromeClientWheelEventHandlerCountChanged();
     99 
    100     wheelEventHandlerCountChanged(document);
    101 }
    102 
    103 void WheelController::didAddEventListener(DOMWindow* window, const AtomicString& eventType)
    104 {
    105     if (eventType != EventTypeNames::wheel && eventType != EventTypeNames::mousewheel)
    106         return;
    107 
    108     Document* document = window->document();
    109     didAddWheelEventHandler(document);
    110 }
    111 
    112 void WheelController::didRemoveEventListener(DOMWindow* window, const AtomicString& eventType)
    113 {
    114     if (eventType != EventTypeNames::wheel && eventType != EventTypeNames::mousewheel)
    115         return;
    116 
    117     Document* document = window->document();
    118     didRemoveWheelEventHandler(document);
    119 }
    120 
    121 } // namespace WebCore
    122