/// <summary>
/// Handles shifting of the pool when scrolling.
/// </summary>
/// <param name="direction"></param>
private void HandlePoolShifting(Direction direction)
{
switch (direction)
{
case Direction.Forward:
// If there are no available mapsets then there's no need to do anything.
if (Screen.AvailableMapsets.ElementAtOrDefault(PoolStartingIndex) == null ||
Screen.AvailableMapsets.ElementAtOrDefault(PoolStartingIndex + MAX_MAPSETS_SHOWN) == null)
{
return;
}
var firstMapset = MapsetBuffer.First();
// Check if the object is in the rect of the ScrollContainer.
// If it is, then there's no updating that needs to happen.
if (!Rectangle.Intersect(firstMapset.ScreenRectangle, ScreenRectangle).IsEmpty)
{
return;
}
// Update the mapset's information and y position.
firstMapset.Y = (PoolStartingIndex + MAX_MAPSETS_SHOWN) * DrawableMapset.HEIGHT +
(PoolStartingIndex + MAX_MAPSETS_SHOWN) * YSpacing + YSpaceBeforeFirstSet;
lock (Screen.AvailableMapsets)
firstMapset.UpdateWithNewMapset(Screen.AvailableMapsets[PoolStartingIndex + MAX_MAPSETS_SHOWN],
PoolStartingIndex + MAX_MAPSETS_SHOWN);
// Circuluarly Shift the list forward one.
MapsetBuffer.Remove(firstMapset);
MapsetBuffer.Add(firstMapset);
// Make sure the set is corrected selected/deselected
if (PoolStartingIndex + MAX_MAPSETS_SHOWN == SelectedMapsetIndex)
{
firstMapset.DisplayAsSelected(MapManager.Selected.Value);
}
else
{
firstMapset.DisplayAsDeselected();
}
PoolStartingIndex++;
break;
case Direction.Backward:
// If there are no previous available user then there's no need to shift.
if (Screen.AvailableMapsets.ElementAtOrDefault(PoolStartingIndex - 1) == null)
{
return;
}
var lastMapset = MapsetBuffer.Last();
// Check if the object is in the rect of the ScrollContainer.
// If it is, then there's no updating that needs to happen.
if (!Rectangle.Intersect(lastMapset.ScreenRectangle, ScreenRectangle).IsEmpty)
{
return;
}
lastMapset.Y = (PoolStartingIndex - 1) * DrawableMapset.HEIGHT + (PoolStartingIndex - 1) * YSpacing + YSpaceBeforeFirstSet;
lock (Screen.AvailableMapsets)
lastMapset.UpdateWithNewMapset(Screen.AvailableMapsets[PoolStartingIndex - 1], PoolStartingIndex - 1);
MapsetBuffer.Remove(lastMapset);
MapsetBuffer.Insert(0, lastMapset);
// Make sure the set is correctly selected/deselected.
if (PoolStartingIndex - 1 == SelectedMapsetIndex)
{
lastMapset.DisplayAsSelected(MapManager.Selected.Value);
}
else
{
lastMapset.DisplayAsDeselected();
}
PoolStartingIndex--;
break;
default:
throw new ArgumentOutOfRangeException(nameof(direction), direction, null);
}
}