static nsIFrame*
GetClosest(nsIFrame* aRoot, const nsPoint& aPointRelativeToRootFrame,
const nsRect& aTargetRect, const EventRadiusPrefs* aPrefs,
nsIFrame* aRestrictToDescendants, nsTArray<nsIFrame*>& aCandidates)
{
nsIFrame* bestTarget = nullptr;
// Lower is better; distance is in appunits
float bestDistance = 1e6f;
nsRegion exposedRegion(aTargetRect);
for (uint32_t i = 0; i < aCandidates.Length(); ++i) {
nsIFrame* f = aCandidates[i];
bool preservesAxisAlignedRectangles = false;
nsRect borderBox = nsLayoutUtils::TransformFrameRectToAncestor(f,
nsRect(nsPoint(0, 0), f->GetSize()), aRoot, &preservesAxisAlignedRectangles);
nsRegion region;
region.And(exposedRegion, borderBox);
if (region.IsEmpty()) {
continue;
}
if (preservesAxisAlignedRectangles) {
// Subtract from the exposed region if we have a transform that won't make
// the bounds include a bunch of area that we don't actually cover.
SubtractFromExposedRegion(&exposedRegion, region);
}
if (!IsElementClickable(f)) {
continue;
}
// If our current closest frame is a descendant of 'f', skip 'f' (prefer
// the nested frame).
if (bestTarget && nsLayoutUtils::IsProperAncestorFrameCrossDoc(f, bestTarget, aRoot)) {
continue;
}
if (!nsLayoutUtils::IsAncestorFrameCrossDoc(aRestrictToDescendants, f, aRoot)) {
continue;
}
// distance is in appunits
float distance = ComputeDistanceFromRegion(aPointRelativeToRootFrame, region);
nsIContent* content = f->GetContent();
if (content && content->IsElement() &&
content->AsElement()->State().HasState(
EventStates(NS_EVENT_STATE_VISITED))) {
distance *= aPrefs->mVisitedWeight / 100.0f;
}
if (distance < bestDistance) {
bestDistance = distance;
bestTarget = f;
}
}
return bestTarget;
}
nsIFrame*
FindFrameTargetedByInputEvent(const WidgetGUIEvent* aEvent,
nsIFrame* aRootFrame,
const nsPoint& aPointRelativeToRootFrame,
uint32_t aFlags)
{
uint32_t flags = (aFlags & INPUT_IGNORE_ROOT_SCROLL_FRAME) ?
nsLayoutUtils::IGNORE_ROOT_SCROLL_FRAME : 0;
nsIFrame* target =
nsLayoutUtils::GetFrameForPoint(aRootFrame, aPointRelativeToRootFrame, flags);
const EventRadiusPrefs* prefs = GetPrefsFor(aEvent->eventStructType);
if (!prefs || !prefs->mEnabled || (target && IsElementClickable(target, nsGkAtoms::body))) {
return target;
}
// Do not modify targeting for actual mouse hardware; only for mouse
// events generated by touch-screen hardware.
if (aEvent->eventStructType == NS_MOUSE_EVENT &&
prefs->mTouchOnly &&
aEvent->AsMouseEvent()->inputSource !=
nsIDOMMouseEvent::MOZ_SOURCE_TOUCH) {
return target;
}
// If the exact target is non-null, only consider candidate targets in the same
// document as the exact target. Otherwise, if an ancestor document has
// a mouse event handler for example, targets that are !IsElementClickable can
// never be targeted --- something nsSubDocumentFrame in an ancestor document
// would be targeted instead.
nsIFrame* restrictToDescendants = target ?
target->PresContext()->PresShell()->GetRootFrame() : aRootFrame;
nsRect targetRect = GetTargetRect(aRootFrame, aPointRelativeToRootFrame,
restrictToDescendants, prefs);
nsAutoTArray<nsIFrame*,8> candidates;
nsresult rv = nsLayoutUtils::GetFramesForArea(aRootFrame, targetRect, candidates, flags);
if (NS_FAILED(rv)) {
return target;
}
nsIFrame* closestClickable =
GetClosest(aRootFrame, aPointRelativeToRootFrame, targetRect, prefs,
restrictToDescendants, candidates);
return closestClickable ? closestClickable : target;
}
nsIFrame*
FindFrameTargetedByInputEvent(WidgetGUIEvent* aEvent,
nsIFrame* aRootFrame,
const nsPoint& aPointRelativeToRootFrame,
uint32_t aFlags)
{
uint32_t flags = (aFlags & INPUT_IGNORE_ROOT_SCROLL_FRAME) ?
nsLayoutUtils::IGNORE_ROOT_SCROLL_FRAME : 0;
nsIFrame* target =
nsLayoutUtils::GetFrameForPoint(aRootFrame, aPointRelativeToRootFrame, flags);
PET_LOG("Found initial target %p for event class %s point %s relative to root frame %p\n",
target, (aEvent->mClass == eMouseEventClass ? "mouse" :
(aEvent->mClass == eTouchEventClass ? "touch" : "other")),
mozilla::layers::Stringify(aPointRelativeToRootFrame).c_str(), aRootFrame);
const EventRadiusPrefs* prefs = GetPrefsFor(aEvent->mClass);
if (!prefs || !prefs->mEnabled) {
PET_LOG("Retargeting disabled\n");
return target;
}
if (target && IsElementClickable(target, nsGkAtoms::body)) {
if (!IsElementClickableAndReadable(target, aEvent, prefs)) {
aEvent->AsMouseEventBase()->hitCluster = true;
}
PET_LOG("Target %p is clickable\n", target);
return target;
}
// Do not modify targeting for actual mouse hardware; only for mouse
// events generated by touch-screen hardware.
if (aEvent->mClass == eMouseEventClass &&
prefs->mTouchOnly &&
aEvent->AsMouseEvent()->inputSource !=
nsIDOMMouseEvent::MOZ_SOURCE_TOUCH) {
PET_LOG("Mouse input event is not from a touch source\n");
return target;
}
// If the exact target is non-null, only consider candidate targets in the same
// document as the exact target. Otherwise, if an ancestor document has
// a mouse event handler for example, targets that are !IsElementClickable can
// never be targeted --- something nsSubDocumentFrame in an ancestor document
// would be targeted instead.
nsIFrame* restrictToDescendants = target ?
target->PresContext()->PresShell()->GetRootFrame() : aRootFrame;
nsRect targetRect = GetTargetRect(aRootFrame, aPointRelativeToRootFrame,
restrictToDescendants, prefs, aFlags);
PET_LOG("Expanded point to target rect %s\n",
mozilla::layers::Stringify(targetRect).c_str());
nsAutoTArray<nsIFrame*,8> candidates;
nsresult rv = nsLayoutUtils::GetFramesForArea(aRootFrame, targetRect, candidates, flags);
if (NS_FAILED(rv)) {
return target;
}
int32_t elementsInCluster = 0;
nsIFrame* closestClickable =
GetClosest(aRootFrame, aPointRelativeToRootFrame, targetRect, prefs,
restrictToDescendants, candidates, &elementsInCluster);
if (closestClickable) {
if ((!prefs->mTouchClusterDetectionDisabled && elementsInCluster > 1) ||
(!IsElementClickableAndReadable(closestClickable, aEvent, prefs))) {
if (aEvent->mClass == eMouseEventClass) {
WidgetMouseEventBase* mouseEventBase = aEvent->AsMouseEventBase();
mouseEventBase->hitCluster = true;
}
}
target = closestClickable;
}
PET_LOG("Final target is %p\n", target);
// Uncomment this to dump the frame tree to help with debugging.
// Note that dumping the frame tree at the top of the function may flood
// logcat on Android devices and cause the PET_LOGs to get dropped.
// aRootFrame->DumpFrameTree();
if (!target || !prefs->mRepositionEventCoords) {
// No repositioning required for this event
return target;
}
// Take the point relative to the root frame, make it relative to the target,
// clamp it to the bounds, and then make it relative to the root frame again.
nsPoint point = aPointRelativeToRootFrame;
if (nsLayoutUtils::TRANSFORM_SUCCEEDED != nsLayoutUtils::TransformPoint(aRootFrame, target, point)) {
return target;
}
point = target->GetRectRelativeToSelf().ClampPoint(point);
if (nsLayoutUtils::TRANSFORM_SUCCEEDED != nsLayoutUtils::TransformPoint(target, aRootFrame, point)) {
return target;
}
// Now we basically undo the operations in GetEventCoordinatesRelativeTo, to
// get back the (now-clamped) coordinates in the event's widget's space.
nsView* view = aRootFrame->GetView();
if (!view) {
return target;
}
LayoutDeviceIntPoint widgetPoint = nsLayoutUtils::TranslateViewToWidget(
aRootFrame->PresContext(), view, point, aEvent->widget);
if (widgetPoint.x != NS_UNCONSTRAINEDSIZE) {
// If that succeeded, we update the point in the event
aEvent->refPoint = widgetPoint;
}
return target;
}
static nsIFrame*
GetClosest(nsIFrame* aRoot, const nsPoint& aPointRelativeToRootFrame,
const nsRect& aTargetRect, const EventRadiusPrefs* aPrefs,
nsIFrame* aRestrictToDescendants, nsTArray<nsIFrame*>& aCandidates,
int32_t* aElementsInCluster)
{
nsIFrame* bestTarget = nullptr;
// Lower is better; distance is in appunits
float bestDistance = 1e6f;
nsRegion exposedRegion(aTargetRect);
for (uint32_t i = 0; i < aCandidates.Length(); ++i) {
nsIFrame* f = aCandidates[i];
PET_LOG("Checking candidate %p\n", f);
bool preservesAxisAlignedRectangles = false;
nsRect borderBox = nsLayoutUtils::TransformFrameRectToAncestor(f,
nsRect(nsPoint(0, 0), f->GetSize()), aRoot, &preservesAxisAlignedRectangles);
nsRegion region;
region.And(exposedRegion, borderBox);
if (region.IsEmpty()) {
PET_LOG(" candidate %p had empty hit region\n", f);
continue;
}
if (preservesAxisAlignedRectangles) {
// Subtract from the exposed region if we have a transform that won't make
// the bounds include a bunch of area that we don't actually cover.
SubtractFromExposedRegion(&exposedRegion, region);
}
nsAutoString labelTargetId;
if (!IsElementClickable(f, nsGkAtoms::body, &labelTargetId)) {
PET_LOG(" candidate %p was not clickable\n", f);
continue;
}
// If our current closest frame is a descendant of 'f', skip 'f' (prefer
// the nested frame).
if (bestTarget && nsLayoutUtils::IsProperAncestorFrameCrossDoc(f, bestTarget, aRoot)) {
PET_LOG(" candidate %p was ancestor for bestTarget %p\n", f, bestTarget);
continue;
}
if (!nsLayoutUtils::IsAncestorFrameCrossDoc(aRestrictToDescendants, f, aRoot)) {
PET_LOG(" candidate %p was not descendant of restrictroot %p\n", f, aRestrictToDescendants);
continue;
}
// If the first clickable ancestor of f is a label element
// and "for" attribute is present in label element, search the frame list for the "for" element
// If this element is present in the current list, do not count the frame in
// the cluster elements counter
if (labelTargetId.IsEmpty() || !IsElementPresent(aCandidates, labelTargetId)) {
(*aElementsInCluster)++;
}
// distance is in appunits
float distance = ComputeDistanceFromRegion(aPointRelativeToRootFrame, region);
nsIContent* content = f->GetContent();
if (content && content->IsElement() &&
content->AsElement()->State().HasState(
EventStates(NS_EVENT_STATE_VISITED))) {
distance *= aPrefs->mVisitedWeight / 100.0f;
}
if (distance < bestDistance) {
PET_LOG(" candidate %p is the new best\n", f);
bestDistance = distance;
bestTarget = f;
}
}
return bestTarget;
}
