/// <summary>
/// When dragging is occurring this will be called every time the cursor is moved.
/// </summary>
/// <param name="eventData">Current event data.</param>
public virtual void OnDrag(PointerEventData eventData)
{
if (!IsDragged)
{
return;
}
oldTarget = currentTarget;
currentTarget = FindTarget(eventData);
if ((oldTarget != null) && (currentTarget != oldTarget))
{
oldTarget.DropCanceled(Data, eventData);
}
if (currentTarget != null)
{
// set cursor can drop
Cursor.SetCursor(AllowDropCursor, AllowDropCursorHotSpot, Compatibility.GetCursorMode());
}
else
{
// set cursor fail drop
Cursor.SetCursor(DeniedDropCursor, DeniedDropCursorHotSpot, Compatibility.GetCursorMode());
}
Vector2 point;
if (!RectTransformUtility.ScreenPointToLocalPointInRectangle(CanvasTransform as RectTransform, Input.mousePosition, eventData.pressEventCamera, out point))
{
return;
}
DragPoint.localPosition = point;
}
/// <summary>
/// Find current target.
/// </summary>
/// <param name="eventData">Event data.</param>
protected virtual void FindCurrentTarget(PointerEventData eventData)
{
var new_target = FindTarget(eventData);
if (new_target != CurrentTarget)
{
if (CurrentTarget != null)
{
CurrentTarget.DropCanceled(Data, eventData);
}
OnTargetChanged(CurrentTarget, new_target);
}
if (new_target != null)
{
// set cursor can drop
Cursor.SetCursor(AllowDropCursor, AllowDropCursorHotSpot, Compatibility.GetCursorMode());
}
else
{
// set cursor fail drop
Cursor.SetCursor(DeniedDropCursor, DeniedDropCursorHotSpot, Compatibility.GetCursorMode());
}
CurrentTarget = new_target;
}
/// <summary>
/// Check if target can receive drop.
/// </summary>
/// <param name="target">Target.</param>
/// <param name="eventData">Event data.</param>
/// <returns>true if target can receive drop; otherwise false.</returns>
protected override bool CheckTarget(IDropSupport <TData> target, PointerEventData eventData)
{
var track_bg = CurrentTarget as TrackBackgroundBase <TData, TPoint>;
if (track_bg != null)
{
track_bg.DragPositionPadding = DragPositionPadding;
}
return(base.CheckTarget(target, eventData));
}
/// <summary>
/// Check if target can receive drop.
/// </summary>
/// <param name="target">Target.</param>
/// <param name="eventData">Event data.</param>
/// <returns>true if target can receive drop; otherwise false.</returns>
protected virtual bool CheckTarget(IDropSupport <T> target, PointerEventData eventData)
{
return(target.CanReceiveDrop(Data, eventData));
}
/// <summary>
/// Process current drop target changed event.
/// </summary>
/// <param name="old">Previous drop target.</param>
/// <param name="current">Current drop target.</param>
protected virtual void OnTargetChanged(IDropSupport <T> old, IDropSupport <T> current)
{
}
/// <summary>
/// Process OnInitializePotentialDrag event.
/// </summary>
/// <param name="eventData">Current event data.</param>
protected virtual void OnInitializePotentialDrag(PointerEventData eventData)
{
CurrentTarget = null;
}
