diff --git a/widget/xpwidgets/ContentHelper.cpp b/widget/xpwidgets/ContentHelper.cpp new file mode 100644 index 00000000000..f7c6698a280 --- /dev/null +++ b/widget/xpwidgets/ContentHelper.cpp @@ -0,0 +1,105 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "ContentHelper.h" +#include "nsQueryFrame.h" +#include "nsIContent.h" +#include "nsIScrollableFrame.h" +#include "nsLayoutUtils.h" +#include "nsStyleConsts.h" +#include "nsView.h" + +namespace mozilla { +namespace widget { + +uint32_t +ContentHelper::GetTouchActionFromFrame(nsIFrame* aFrame) +{ + if (!aFrame || !aFrame->GetContent() || !aFrame->GetContent()->GetPrimaryFrame()) { + // If frame is invalid or null then return default value. + return NS_STYLE_TOUCH_ACTION_AUTO; + } + + if (!aFrame->IsFrameOfType(nsIFrame::eSVG) && !aFrame->IsFrameOfType(nsIFrame::eBlockFrame)) { + // Since touch-action property can be applied to only svg and block-level + // elements we ignore frames of other types. + return NS_STYLE_TOUCH_ACTION_AUTO; + } + + return (aFrame->GetContent()->GetPrimaryFrame()->StyleDisplay()->mTouchAction); +} + +void +ContentHelper::UpdateAllowedBehavior(uint32_t aTouchActionValue, bool aConsiderPanning, TouchBehaviorFlags& aOutBehavior) +{ + if (aTouchActionValue != NS_STYLE_TOUCH_ACTION_AUTO) { + // Dropping zoom flag since zooming requires touch-action values of all touches + // to be AUTO. + aOutBehavior &= ~AllowedTouchBehavior::ZOOM; + } + + if (aConsiderPanning) { + if (aTouchActionValue == NS_STYLE_TOUCH_ACTION_NONE) { + aOutBehavior &= ~AllowedTouchBehavior::VERTICAL_PAN; + aOutBehavior &= ~AllowedTouchBehavior::HORIZONTAL_PAN; + } + + // Values pan-x and pan-y set at the same time to the same element do not affect panning constraints. + // Therefore we need to check whether pan-x is set without pan-y and the same for pan-y. + if ((aTouchActionValue & NS_STYLE_TOUCH_ACTION_PAN_X) && !(aTouchActionValue & NS_STYLE_TOUCH_ACTION_PAN_Y)) { + aOutBehavior &= ~AllowedTouchBehavior::VERTICAL_PAN; + } else if ((aTouchActionValue & NS_STYLE_TOUCH_ACTION_PAN_Y) && !(aTouchActionValue & NS_STYLE_TOUCH_ACTION_PAN_X)) { + aOutBehavior &= ~AllowedTouchBehavior::HORIZONTAL_PAN; + } + } +} + +ContentHelper::TouchBehaviorFlags +ContentHelper::GetAllowedTouchBehavior(nsIWidget* aWidget, const nsIntPoint& aPoint) +{ + nsView *view = nsView::GetViewFor(aWidget); + nsIFrame *viewFrame = view->GetFrame(); + + nsPoint relativePoint = nsLayoutUtils::GetEventCoordinatesRelativeTo(aWidget, aPoint, viewFrame); + + nsIFrame *target = nsLayoutUtils::GetFrameForPoint(viewFrame, relativePoint, nsLayoutUtils::IGNORE_ROOT_SCROLL_FRAME); + nsIScrollableFrame *nearestScrollableParent = nsLayoutUtils::GetNearestScrollableFrame(target, 0); + nsIFrame* nearestScrollableFrame = do_QueryFrame(nearestScrollableParent); + + // We're walking up the DOM tree until we meet the element with touch behavior and accumulating + // touch-action restrictions of all elements in this chain. + // The exact quote from the spec, that clarifies more: + // To determine the effect of a touch, find the nearest ancestor (starting from the element itself) + // that has a default touch behavior. Then examine the touch-action property of each element between + // the hit tested element and the element with the default touch behavior (including both the hit + // tested element and the element with the default touch behavior). If the touch-action property of + // any of those elements disallows the default touch behavior, do nothing. Otherwise allow the element + // to start considering the touch for the purposes of executing a default touch behavior. + + // Currently we support only two touch behaviors: panning and zooming. + // For panning we walk up until we meet the first scrollable element (the element that supports panning) + // or root element. + // For zooming we walk up until the root element since Firefox currently supports only zooming of the + // root frame but not the subframes. + + bool considerPanning = true; + TouchBehaviorFlags behavior = AllowedTouchBehavior::VERTICAL_PAN | AllowedTouchBehavior::HORIZONTAL_PAN | + AllowedTouchBehavior::ZOOM; + + for (nsIFrame *frame = target; frame && frame->GetContent() && behavior; frame = frame->GetParent()) { + UpdateAllowedBehavior(GetTouchActionFromFrame(frame), considerPanning, behavior); + + if (frame == nearestScrollableFrame) { + // We met the scrollable element, after it we shouldn't consider touch-action + // values for the purpose of panning but only for zooming. + considerPanning = false; + } + } + + return behavior; +} + +} +} \ No newline at end of file diff --git a/widget/xpwidgets/ContentHelper.h b/widget/xpwidgets/ContentHelper.h new file mode 100644 index 00000000000..6e818a3bc67 --- /dev/null +++ b/widget/xpwidgets/ContentHelper.h @@ -0,0 +1,40 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef __mozilla_widget_ContentHelper_h__ +#define __mozilla_widget_ContentHelper_h__ + +#include "nsIFrame.h" +#include "nsIWidget.h" +#include "mozilla/layers/APZCTreeManager.h" + +namespace mozilla { +namespace widget { + +/* + * Allow different platform widgets to access Content/DOM stuff. + */ +class ContentHelper +{ + typedef mozilla::layers::AllowedTouchBehavior AllowedTouchBehavior; + typedef uint32_t TouchBehaviorFlags; + +private: + static uint32_t GetTouchActionFromFrame(nsIFrame* aFrame); + static void UpdateAllowedBehavior(uint32_t aTouchActionValue, bool aConsiderPanning, TouchBehaviorFlags& aOutBehavior); + +public: + /* + * Performs hit testing on content, finds frame that corresponds to the aPoint and retrieves + * touch-action css property value from it according the rules specified in the spec: + * http://www.w3.org/TR/pointerevents/#the-touch-action-css-property. + */ + static TouchBehaviorFlags GetAllowedTouchBehavior(nsIWidget* aWidget, const nsIntPoint& aPoint); +}; + +} +} + +#endif /*__mozilla_widget_ContentHelper_h__ */ \ No newline at end of file diff --git a/widget/xpwidgets/moz.build b/widget/xpwidgets/moz.build index ad66c3c5b96..624fd0e8365 100644 --- a/widget/xpwidgets/moz.build +++ b/widget/xpwidgets/moz.build @@ -6,6 +6,7 @@ EXPORTS += [ 'APZCCallbackHelper.h', + 'ContentHelper.h', 'GfxDriverInfo.h', 'GfxInfoBase.h', 'GfxInfoCollector.h', @@ -13,6 +14,7 @@ EXPORTS += [ UNIFIED_SOURCES += [ 'APZCCallbackHelper.cpp', + 'ContentHelper.cpp', 'GfxDriverInfo.cpp', 'GfxInfoBase.cpp', 'GfxInfoCollector.cpp',