public void OnBeginDrag(PointerEventData eventData)
{
this.startParent = transform.GetComponentInParent <ProjectCardDropTarget>();
this.startIndex = transform.GetSiblingIndex();
// reparent this to the root Canvas so it isn't clipped.
this.transform.SetParent(GetComponentInParent <Canvas>().transform, false);
GetComponent <LayoutElement>().ignoreLayout = true;
this.startParent.OnCardRemoved(GetComponent <ProjectCard>());
}
public void OnDrag(PointerEventData eventData)
{
transform.position = eventData.position;
ProjectCardDropTarget nextHovered = GetHoveredDropTarget(eventData);
// Update the hovered container.
if (nextHovered != currentHovered)
{
Destroy(cardSurrogate);
currentHovered = nextHovered;
if (currentHovered != null)
{
cardSurrogate = Instantiate(cardSurrogatePrefab);
cardSurrogate.transform.SetParent(currentHovered.CardContainer, false);
// We need fresh position data when we are determining the surrogate's child index later.
LayoutRebuilder.ForceRebuildLayoutImmediate(currentHovered.CardContainer);
}
}
if (currentHovered == null)
{
return;
}
// Move the surrogate to the index of the closest object within the hovered container.
// There is guaranteed to be at least one child - the surrogate - which simplifies the loop a bit.
int minDistanceIndex = 0;
for (int i = 1; i < currentHovered.CardContainer.childCount; i++)
{
float childDistance = (currentHovered.CardContainer.GetChild(i).transform.position - transform.position)
.sqrMagnitude;
float minDistance = (currentHovered.CardContainer.GetChild(minDistanceIndex).transform.position - transform.position)
.sqrMagnitude;
if (childDistance < minDistance)
{
minDistanceIndex = i;
}
}
cardSurrogate.transform.SetSiblingIndex(minDistanceIndex);
}
public void OnEndDrag(PointerEventData eventData)
{
if (currentHovered != null)
{
// Complete the drag, inserting into the current target.
transform.SetParent(currentHovered.CardContainer, false);
transform.SetSiblingIndex(cardSurrogate.transform.GetSiblingIndex());
Destroy(cardSurrogate);
currentHovered = null;
}
else
{
// Revert the drag if we were not dropped onto a target.
transform.SetParent(startParent.CardContainer, false);
transform.SetSiblingIndex(startIndex);
}
GetComponentInParent <ProjectCardDropTarget>().OnCardAdded(GetComponent <ProjectCard>());
GetComponent <LayoutElement>().ignoreLayout = false;
}
