/// <summary>Recycle the DragEvent, to be re-used by a later caller.</summary>
/// <remarks>
/// Recycle the DragEvent, to be re-used by a later caller. After calling
/// this function you must never touch the event again.
/// </remarks>
/// <hide></hide>
public void recycle()
{
// Ensure recycle is only called once!
if (mRecycled)
{
throw new java.lang.RuntimeException(ToString() + " recycled twice!");
}
mRecycled = true;
mClipData = null;
mClipDescription = null;
mLocalState = null;
lock (gRecyclerLock)
{
if (gRecyclerUsed < MAX_RECYCLED)
{
gRecyclerUsed++;
mNext = gRecyclerTop;
gRecyclerTop = this;
}
}
}
/// <hide></hide>
public static android.view.DragEvent obtain(int action, float x, float y, object
localState, android.content.ClipDescription description, android.content.ClipData
data, bool result)
{
android.view.DragEvent ev;
lock (gRecyclerLock)
{
if (gRecyclerTop == null)
{
ev = new android.view.DragEvent();
ev.init(action, x, y, description, data, localState, result);
return(ev);
}
ev = gRecyclerTop;
gRecyclerTop = ev.mNext;
gRecyclerUsed -= 1;
}
ev.mRecycledLocation = null;
ev.mRecycled = false;
ev.mNext = null;
ev.init(action, x, y, description, data, localState, result);
return(ev);
}
/// <hide></hide>
public static android.view.DragEvent obtain(android.view.DragEvent source)
{
return(obtain(source.mAction, source.mX, source.mY, source.mLocalState, source.mClipDescription
, source.mClipData, source.mDragResult));
}
internal override void dispatchDetachedFromWindow()
{
// If we still have a touch target, we are still in the process of
// dispatching motion events to a child; we need to get rid of that
// child to avoid dispatching events to it after the window is torn
// down. To make sure we keep the child in a consistent state, we
// first send it an ACTION_CANCEL motion event.
cancelAndClearTouchTargets(null);
// In case view is detached while transition is running
mLayoutSuppressed = false;
// Tear down our drag tracking
mDragNotifiedChildren = null;
if (mCurrentDrag != null)
{
mCurrentDrag.recycle();
mCurrentDrag = null;
}
int count = mChildrenCount;
android.view.View[] children = mChildren;
{
for (int i = 0; i < count; i++)
{
children[i].dispatchDetachedFromWindow();
}
}
base.dispatchDetachedFromWindow();
}
public override bool dispatchDragEvent(android.view.DragEvent @event)
{
bool retval = false;
float tx = @event.mX;
float ty = @event.mY;
android.view.ViewRootImpl root = getViewRootImpl();
switch (@event.mAction)
{
case android.view.DragEvent.ACTION_DRAG_STARTED:
{
// Dispatch down the view hierarchy
// clear state to recalculate which views we drag over
mCurrentDragView = null;
// Set up our tracking of drag-started notifications
mCurrentDrag = android.view.DragEvent.obtain(@event);
if (mDragNotifiedChildren == null)
{
mDragNotifiedChildren = new java.util.HashSet<android.view.View>();
}
else
{
mDragNotifiedChildren.clear();
}
// Now dispatch down to our children, caching the responses
mChildAcceptsDrag = false;
int count = mChildrenCount;
android.view.View[] children = mChildren;
{
for (int i = 0; i < count; i++)
{
android.view.View child = children[i];
child.mPrivateFlags2 &= ~android.view.View.DRAG_MASK;
if (child.getVisibility() == VISIBLE)
{
bool handled = notifyChildOfDrag(children[i]);
if (handled)
{
mChildAcceptsDrag = true;
}
}
}
}
// Return HANDLED if one of our children can accept the drag
if (mChildAcceptsDrag)
{
retval = true;
}
break;
}
case android.view.DragEvent.ACTION_DRAG_ENDED:
{
// Release the bookkeeping now that the drag lifecycle has ended
if (mDragNotifiedChildren != null)
{
foreach (android.view.View child in Sharpen.IterableProxy.Create(mDragNotifiedChildren
))
{
// If a child was notified about an ongoing drag, it's told that it's over
child.dispatchDragEvent(@event);
child.mPrivateFlags2 &= ~android.view.View.DRAG_MASK;
child.refreshDrawableState();
}
mDragNotifiedChildren.clear();
mCurrentDrag.recycle();
mCurrentDrag = null;
}
// We consider drag-ended to have been handled if one of our children
// had offered to handle the drag.
if (mChildAcceptsDrag)
{
retval = true;
}
break;
}
case android.view.DragEvent.ACTION_DRAG_LOCATION:
{
// Find the [possibly new] drag target
android.view.View target = findFrontmostDroppableChildAt(@event.mX, @event.mY, mLocalPoint
);
// If we've changed apparent drag target, tell the view root which view
// we're over now [for purposes of the eventual drag-recipient-changed
// notifications to the framework] and tell the new target that the drag
// has entered its bounds. The root will see setDragFocus() calls all
// the way down to the final leaf view that is handling the LOCATION event
// before reporting the new potential recipient to the framework.
if (mCurrentDragView != target)
{
root.setDragFocus(target);
int action = @event.mAction;
// If we've dragged off of a child view, send it the EXITED message
if (mCurrentDragView != null)
{
android.view.View view = mCurrentDragView;
@event.mAction = android.view.DragEvent.ACTION_DRAG_EXITED;
view.dispatchDragEvent(@event);
view.mPrivateFlags2 &= ~android.view.View.DRAG_HOVERED;
view.refreshDrawableState();
}
mCurrentDragView = target;
// If we've dragged over a new child view, send it the ENTERED message
if (target != null)
{
@event.mAction = android.view.DragEvent.ACTION_DRAG_ENTERED;
target.dispatchDragEvent(@event);
target.mPrivateFlags2 |= android.view.View.DRAG_HOVERED;
target.refreshDrawableState();
}
@event.mAction = action;
}
// restore the event's original state
// Dispatch the actual drag location notice, localized into its coordinates
if (target != null)
{
@event.mX = mLocalPoint.x;
@event.mY = mLocalPoint.y;
retval = target.dispatchDragEvent(@event);
@event.mX = tx;
@event.mY = ty;
}
break;
}
case android.view.DragEvent.ACTION_DRAG_EXITED:
{
if (mCurrentDragView != null)
{
android.view.View view = mCurrentDragView;
view.dispatchDragEvent(@event);
view.mPrivateFlags2 &= ~android.view.View.DRAG_HOVERED;
view.refreshDrawableState();
mCurrentDragView = null;
}
break;
}
case android.view.DragEvent.ACTION_DROP:
{
android.view.View target = findFrontmostDroppableChildAt(@event.mX, @event.mY, mLocalPoint
);
if (target != null)
{
@event.mX = mLocalPoint.x;
@event.mY = mLocalPoint.y;
retval = target.dispatchDragEvent(@event);
@event.mX = tx;
@event.mY = ty;
}
break;
}
}
// If none of our children could handle the event, try here
if (!retval)
{
// Call up to the View implementation that dispatches to installed listeners
retval = base.dispatchDragEvent(@event);
}
return retval;
}
public virtual bool onDragEvent(DragEvent @event)
{
return(false);
}
public override void dispatchDragEvent(android.view.DragEvent @event)
{
throw new System.NotImplementedException();
}
public abstract void dispatchDragEvent(android.view.DragEvent arg1);
