// The hovered child view.
// The next target in the target list.
public static android.view.ViewGroup.HoverTarget obtain(android.view.View child)
{
android.view.ViewGroup.HoverTarget target;
lock (sRecycleLock)
{
if (sRecycleBin == null)
{
target = new android.view.ViewGroup.HoverTarget();
}
else
{
target = sRecycleBin;
sRecycleBin = target.next;
sRecycledCount--;
target.next = null;
}
}
target.child = child;
return target;
}
public void recycle()
{
lock (sRecycleLock)
{
if (sRecycledCount < MAX_RECYCLED)
{
next = sRecycleBin;
sRecycleBin = this;
sRecycledCount += 1;
}
else
{
next = null;
}
child = null;
}
}
protected internal override bool dispatchHoverEvent(android.view.MotionEvent @event
)
{
int action = @event.getAction();
// First check whether the view group wants to intercept the hover event.
bool interceptHover = onInterceptHoverEvent(@event);
@event.setAction(action);
// restore action in case it was changed
android.view.MotionEvent eventNoHistory = @event;
bool handled = false;
// Send events to the hovered children and build a new list of hover targets until
// one is found that handles the event.
android.view.ViewGroup.HoverTarget firstOldHoverTarget = mFirstHoverTarget;
mFirstHoverTarget = null;
if (!interceptHover && action != android.view.MotionEvent.ACTION_HOVER_EXIT)
{
float x = @event.getX();
float y = @event.getY();
int childrenCount = mChildrenCount;
if (childrenCount != 0)
{
android.view.View[] children = mChildren;
android.view.ViewGroup.HoverTarget lastHoverTarget = null;
{
for (int i = childrenCount - 1; i >= 0; i--)
{
android.view.View child = children[i];
if (!canViewReceivePointerEvents(child) || !isTransformedTouchPointInView(x, y, child
, null))
{
continue;
}
// Obtain a hover target for this child. Dequeue it from the
// old hover target list if the child was previously hovered.
android.view.ViewGroup.HoverTarget hoverTarget = firstOldHoverTarget;
bool wasHovered;
{
for (android.view.ViewGroup.HoverTarget predecessor = null; ; )
{
if (hoverTarget == null)
{
hoverTarget = android.view.ViewGroup.HoverTarget.obtain(child);
wasHovered = false;
break;
}
if (hoverTarget.child == child)
{
if (predecessor != null)
{
predecessor.next = hoverTarget.next;
}
else
{
firstOldHoverTarget = hoverTarget.next;
}
hoverTarget.next = null;
wasHovered = true;
break;
}
predecessor = hoverTarget;
hoverTarget = hoverTarget.next;
}
}
// Enqueue the hover target onto the new hover target list.
if (lastHoverTarget != null)
{
lastHoverTarget.next = hoverTarget;
}
else
{
lastHoverTarget = hoverTarget;
mFirstHoverTarget = hoverTarget;
}
// Dispatch the event to the child.
if (action == android.view.MotionEvent.ACTION_HOVER_ENTER)
{
if (!wasHovered)
{
// Send the enter as is.
handled |= dispatchTransformedGenericPointerEvent(@event, child);
}
}
else
{
// enter
if (action == android.view.MotionEvent.ACTION_HOVER_MOVE)
{
if (!wasHovered)
{
// Synthesize an enter from a move.
eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory);
eventNoHistory.setAction(android.view.MotionEvent.ACTION_HOVER_ENTER);
handled |= dispatchTransformedGenericPointerEvent(eventNoHistory, child);
// enter
eventNoHistory.setAction(action);
handled |= dispatchTransformedGenericPointerEvent(eventNoHistory, child);
}
else
{
// move
// Send the move as is.
handled |= dispatchTransformedGenericPointerEvent(@event, child);
}
}
}
if (handled)
{
break;
}
}
}
}
}
// Send exit events to all previously hovered children that are no longer hovered.
while (firstOldHoverTarget != null)
{
android.view.View child = firstOldHoverTarget.child;
// Exit the old hovered child.
if (action == android.view.MotionEvent.ACTION_HOVER_EXIT)
{
// Send the exit as is.
handled |= dispatchTransformedGenericPointerEvent(@event, child);
}
else
{
// exit
// Synthesize an exit from a move or enter.
// Ignore the result because hover focus has moved to a different view.
if (action == android.view.MotionEvent.ACTION_HOVER_MOVE)
{
dispatchTransformedGenericPointerEvent(@event, child);
}
// move
eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory);
eventNoHistory.setAction(android.view.MotionEvent.ACTION_HOVER_EXIT);
dispatchTransformedGenericPointerEvent(eventNoHistory, child);
// exit
eventNoHistory.setAction(action);
}
android.view.ViewGroup.HoverTarget nextOldHoverTarget = firstOldHoverTarget.next;
firstOldHoverTarget.recycle();
firstOldHoverTarget = nextOldHoverTarget;
}
// Send events to the view group itself if no children have handled it.
bool newHoveredSelf = !handled;
if (newHoveredSelf == mHoveredSelf)
{
if (newHoveredSelf)
{
// Send event to the view group as before.
handled |= base.dispatchHoverEvent(@event);
}
}
else
{
if (mHoveredSelf)
{
// Exit the view group.
if (action == android.view.MotionEvent.ACTION_HOVER_EXIT)
{
// Send the exit as is.
handled |= base.dispatchHoverEvent(@event);
}
else
{
// exit
// Synthesize an exit from a move or enter.
// Ignore the result because hover focus is moving to a different view.
if (action == android.view.MotionEvent.ACTION_HOVER_MOVE)
{
base.dispatchHoverEvent(@event);
}
// move
eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory);
eventNoHistory.setAction(android.view.MotionEvent.ACTION_HOVER_EXIT);
base.dispatchHoverEvent(eventNoHistory);
// exit
eventNoHistory.setAction(action);
}
mHoveredSelf = false;
}
if (newHoveredSelf)
{
// Enter the view group.
if (action == android.view.MotionEvent.ACTION_HOVER_ENTER)
{
// Send the enter as is.
handled |= base.dispatchHoverEvent(@event);
// enter
mHoveredSelf = true;
}
else
{
if (action == android.view.MotionEvent.ACTION_HOVER_MOVE)
{
// Synthesize an enter from a move.
eventNoHistory = obtainMotionEventNoHistoryOrSelf(eventNoHistory);
eventNoHistory.setAction(android.view.MotionEvent.ACTION_HOVER_ENTER);
handled |= base.dispatchHoverEvent(eventNoHistory);
// enter
eventNoHistory.setAction(action);
handled |= base.dispatchHoverEvent(eventNoHistory);
// move
mHoveredSelf = true;
}
}
}
}
// Recycle the copy of the event that we made.
if (eventNoHistory != @event)
{
eventNoHistory.recycle();
}
// Done.
return handled;
}