public override int FindTargetSnapPosition(RecyclerView.LayoutManager layoutManager, int velocityX, int velocityY)
{
//throw new NotImplementedException();
int target = RecyclerView.NoPosition;//.NO_POSITION;
Loge("findTargetSnapPosition, velocityX = " + velocityX + ", velocityY" + velocityY);
if (null != layoutManager && layoutManager is PagerGridLayoutManager)
{
PagerGridLayoutManager manager = (PagerGridLayoutManager)layoutManager;
if (manager.CanScrollHorizontally())
{
if (velocityX > PagerConfig.GetFlingThreshold())
{
target = manager.FindNextPageFirstPos();
}
else if (velocityX < -PagerConfig.GetFlingThreshold())
{
target = manager.FindPrePageFirstPos();
}
}
else if (manager.CanScrollVertically())
{
if (velocityY > PagerConfig.GetFlingThreshold())
{
target = manager.FindNextPageFirstPos();
}
else if (velocityY < -PagerConfig.GetFlingThreshold())
{
target = manager.FindPrePageFirstPos();
}
}
}
Loge("findTargetSnapPosition, target = " + target);
return(target);
}
public override View FindSnapView(RecyclerView.LayoutManager layoutManager)
{
//throw new NotImplementedException();
if (layoutManager is PagerGridLayoutManager)
{
PagerGridLayoutManager manager = (PagerGridLayoutManager)layoutManager;
return(manager.FindSnapView());
}
return(null);
}
public override int[] CalculateDistanceToFinalSnap(RecyclerView.LayoutManager layoutManager, View targetView)
{
//throw new NotImplementedException();
int pos = layoutManager.GetPosition(targetView);
Loge("findTargetSnapPosition, pos = " + pos);
int[] offset = new int[2];
if (layoutManager is PagerGridLayoutManager)
{
PagerGridLayoutManager manager = (PagerGridLayoutManager)layoutManager;
offset = manager.GetSnapOffset(pos);
}
return(offset);
}
protected override void OnTargetFound(View targetView, RecyclerView.State state, Action action)
{
RecyclerView.LayoutManager manager = mRecyclerView.GetLayoutManager();
if (null == manager)
{
return;
}
if (manager is PagerGridLayoutManager)
{
PagerGridLayoutManager layoutManager = (PagerGridLayoutManager)manager;
int pos = mRecyclerView.GetChildAdapterPosition(targetView);
int[] snapDistances = layoutManager.GetSnapOffset(pos);
int dx = snapDistances[0];
int dy = snapDistances[1];
Logi("dx = " + dx);
Logi("dy = " + dy);
int time = CalculateTimeForScrolling(Math.Max(Math.Abs(dx), Math.Abs(dy)));
if (time > 0)
{
action.Update(dx, dy, time, new DecelerateInterpolator());
}
}
}