bool ScrollingCoordinator::requestScrollPositionUpdate(FrameView* frameView, const IntPoint& scrollPosition)
{
ASSERT(isMainThread());
ASSERT(m_page);
if (!coordinatesScrollingForFrameView(frameView))
return false;
#if ENABLE(THREADED_SCROLLING)
// Update the main frame scroll position locally before asking the scrolling thread to scroll,
// since FrameView expects scroll position updates to happen synchronously.
updateMainFrameScrollPosition(scrollPosition);
if (frameView->frame()->document()->inPageCache()) {
// If this frame view's document is being put into the page cache, we don't want to update our
// main frame scroll position.
return true;
}
m_scrollingTreeState->setRequestedScrollPosition(scrollPosition);
scheduleTreeStateCommit();
return true;
#else
UNUSED_PARAM(scrollPosition);
return false;
#endif
}
void ScrollingCoordinator::scheduleUpdateMainFrameScrollPosition(const IntPoint& scrollPosition, bool programmaticScroll, SetOrSyncScrollingLayerPosition scrollingLayerPositionAction)
{
if (m_updateMainFrameScrollPositionTimer.isActive()) {
if (m_scheduledUpdateIsProgrammaticScroll == programmaticScroll
&& m_scheduledScrollingLayerPositionAction == scrollingLayerPositionAction) {
m_scheduledUpdateScrollPosition = scrollPosition;
return;
}
// If the parameters don't match what was previosly scheduled, dispatch immediately.
m_updateMainFrameScrollPositionTimer.stop();
updateMainFrameScrollPosition(m_scheduledUpdateScrollPosition, m_scheduledUpdateIsProgrammaticScroll, m_scheduledScrollingLayerPositionAction);
updateMainFrameScrollPosition(scrollPosition, programmaticScroll, scrollingLayerPositionAction);
return;
}
m_scheduledUpdateScrollPosition = scrollPosition;
m_scheduledUpdateIsProgrammaticScroll = programmaticScroll;
m_scheduledScrollingLayerPositionAction = scrollingLayerPositionAction;
m_updateMainFrameScrollPositionTimer.startOneShot(0);
}
void ScrollingCoordinator::updateMainFrameScrollPositionTimerFired(Timer<ScrollingCoordinator>*)
{
updateMainFrameScrollPosition(m_scheduledUpdateScrollPosition, m_scheduledUpdateIsProgrammaticScroll, m_scheduledScrollingLayerPositionAction);
}
