public override View GetViewForPositionAndType(RecyclerView.Recycler recycler, int position, int type)
{
UnoViewHolder result = null;
List <UnoViewHolder> views;
if (!_cachedViews.TryGetValue(type, out views))
{
return(null);
}
//Remove views that are animating out
views.RemoveAll(IsItemUnrecyclable);
foreach (var holder in views)
{
//Look for an exact match
if (holder.LayoutPosition == position)
{
result = holder;
views.Remove(result);
break;
}
}
if (result == null && views.Count > 0)
{
//Get any match of correct type
result = views[views.Count - 1];
views.RemoveAt(views.Count - 1);
}
if (result != null)
{
Layout.AttachView(result.ItemView);
recycler.BindViewToPosition(result.ItemView, position);
if (this.Log().IsEnabled(Uno.Foundation.Logging.LogLevel.Debug))
{
this.Log().Debug($"Returning cached view for position={position} and view type={type}. {views.Count} cached views remaining.");
}
return(result.ItemView);
}
return(null);
}
/// <summary>
/// Retrieve view for <paramref name="displayPosition"/> from intermediate cache.
/// </summary>
private View GetViewFromIntermediateCache(RecyclerView.Recycler recycler, int displayPosition)
{
if (_shouldBlockIntermediateCache)
{
return(null);
}
UnoViewHolder result = null;
List <UnoViewHolder> views;
var type = _owner.CurrentAdapter.GetItemViewType(displayPosition);
if (!_intermediateCache.TryGetValue(type, out views))
{
return(null);
}
//Remove views that are animating out
views.RemoveAll(RemoveUnrecyclable);
foreach (var holder in views)
{
//Look for an exact match
if (holder.LayoutPosition == displayPosition)
{
result = holder;
views.Remove(result);
_owner.CurrentAdapter.RegisterPhaseBinding(result); //Restart phase binding, since this won't be rebound by adapter
break;
}
}
if (result == null && views.Count > 0)
{
// Get any match of correct type except views that could be reused without rebinding
for (int i = views.Count - 1; i >= 0; i--)
{
var view = views[i];
if (!IsInTargetRange(view.LayoutPosition))
{
result = view;
views.RemoveAt(i);
break;
}
}
}
if (result != null)
{
recycler.BindViewToPosition(result.ItemView, displayPosition);
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug($"Returning cached view for position={displayPosition} and view type={type}. {views.Count} cached views remaining.");
}
return(result.ItemView);
}
return(null);
bool RemoveUnrecyclable(UnoViewHolder holderInner)
{
var isUnrecyclable = !holderInner.IsRecyclable;
if (isUnrecyclable)
{
Layout.RemoveAndRecycleView(holderInner.ItemView, recycler);
}
return(isUnrecyclable);
}
}