internal RvAdapter(Context context, IVirtualListViewAdapter adapter)
{
Context = context;
this.adapter = adapter;
templates = new List <Xamarin.Forms.DataTemplate>();
}
public (int realSectionIndex, int realItemIndex) GetRealIndexPath(IVirtualListViewAdapter adapter, int sectionIndex, int itemIndex)
{
var realSectionIndex = sectionIndex;
if (HasGlobalHeader)
{
if (sectionIndex == 0)
{
return(-1, -1);
}
// Global header takes up a section, real adapter is 1 less
realSectionIndex--;
}
var realNumberOfSections = adapter.Sections;
if (HasGlobalFooter)
{
if (realSectionIndex >= realNumberOfSections)
{
return(-1, -1);
}
}
var realItemsInSection = adapter.ItemsForSection(realSectionIndex);
var realItemIndex = itemIndex;
if (HasSectionHeader)
{
realItemIndex--;
if (itemIndex == 0)
{
return(-1, -1);
}
}
if (HasSectionFooter)
{
if (realItemIndex >= realItemsInSection)
{
return(-1, -1);
}
}
return(realSectionIndex, realItemIndex);
}
protected override void OnElementChanged(ElementChangedEventArgs <VirtualListView> e)
{
base.OnElementChanged(e);
// Clean up old
if (e.OldElement != null)
{
}
// Setup new
if (e.NewElement != null)
{
TemplateSelector = CreateTemplateSelector();
Adapter = e.NewElement.Adapter;
// Create the native control
if (Control == null)
{
layout = new CvLayout();
layout.EstimatedItemSize = UICollectionViewFlowLayout.AutomaticSize;
layout.SectionInset = new UIEdgeInsets(0, 0, 0, 0);
layout.MinimumInteritemSpacing = 0f;
layout.MinimumLineSpacing = 0f;
DataSource = new CvDataSource(this);
DataSource.IsSelectedHandler = (realSection, realIndex) =>
e?.NewElement?.IsItemSelected(realSection, realIndex) ?? false;
cvdelegate = new CvDelegate(this);
collectionView = new UICollectionView(this.Frame, layout);
collectionView.AllowsSelection = e.NewElement.SelectionMode != SelectionMode.None;
collectionView.AllowsMultipleSelection = e.NewElement.SelectionMode == SelectionMode.Multiple;
collectionView.DataSource = DataSource;
collectionView.ContentInset = new UIEdgeInsets(0, 0, 0, 0);
collectionView.Delegate = cvdelegate;
SetNativeControl(collectionView);
collectionView.ReloadData();
}
}
}
public int GetTotalCount(IVirtualListViewAdapter adapter)
{
if (adapter == null)
{
return(0);
}
var sum = 0;
if (HeaderTemplate != null)
{
sum += 1;
}
if (adapter != null)
{
for (int i = 0; i < adapter.Sections; i++)
{
if (SectionHeaderTemplate != null || SectionHeaderTemplateSelector != null)
{
sum += 1;
}
sum += adapter.ItemsForSection(i);
if (SectionFooterTemplate != null || SectionFooterTemplateSelector != null)
{
sum += 1;
}
}
}
if (FooterTemplate != null)
{
sum += 1;
}
return(sum);
}
public override DataTemplate SelectItemTemplate(IVirtualListViewAdapter adapter, int sectionIndex, int itemIndex)
{
var item = adapter.Item(sectionIndex, itemIndex);
if (item is TrackInfo trackInfo)
{
var genreId = trackInfo.GenreId;
if (genreId == 9)
{
return(PopTemplate);
}
//if (genreId == 1 || genreId == 3 || genreId == 4 || genreId == 5 || genreId == 13)
// return HeavyTemplate;
else if (genreId == 10 || genreId == 19 || genreId == 18 || genreId == 21 || genreId == 22)
{
return(FilmTemplate);
}
}
return(GenericTemplate);
}
public PositionInfo GetInfo(IVirtualListViewAdapter adapter, int position)
{
if (adapter == null)
{
return(null);
}
var linear = 0;
var numberSections = adapter.Sections;
if (HeaderTemplate != null)
{
if (position == 0)
{
return new PositionInfo
{
Position = position,
Kind = PositionKind.Header
}
}
;
linear++;
}
for (int s = 0; s < numberSections; s++)
{
if (SectionHeaderTemplate != null || SectionHeaderTemplateSelector != null)
{
if (position == linear)
{
return new PositionInfo
{
SectionIndex = s,
Position = position,
BindingContext = adapter.Section(s),
Kind = PositionKind.SectionHeader
}
}
;
linear++;
}
var itemsInSection = adapter.ItemsForSection(s);
// It's an item in the section, return it for this item
if (position < linear + itemsInSection)
{
var itemIndex = position - linear;
return(new PositionInfo
{
SectionIndex = s,
NumberOfSections = numberSections,
ItemIndex = itemIndex,
ItemsInSection = itemsInSection,
Position = position,
BindingContext = adapter.Item(s, itemIndex),
Kind = PositionKind.Item
});
}
linear += itemsInSection;
if (SectionFooterTemplate != null || SectionFooterTemplateSelector != null)
{
if (position == linear)
{
return new PositionInfo
{
SectionIndex = s,
Position = position,
BindingContext = adapter.Section(s),
Kind = PositionKind.SectionFooter
}
}
;
linear++;
}
}
return(new PositionInfo
{
Position = position,
Kind = PositionKind.Footer
});
}
public DataTemplate GetTemplate(IVirtualListViewAdapter adapter, int position)
{
if (position == 0)
{
if (HeaderTemplate != null)
{
return(HeaderTemplate);
}
if (SectionHeaderTemplateSelector != null)
{
return(SectionHeaderTemplateSelector.SelectGroupTemplate(adapter, 0));
}
if (SectionHeaderTemplate != null)
{
return(SectionHeaderTemplate);
}
}
var linear = 0;
if (HeaderTemplate != null)
{
linear++;
}
for (int s = 0; s < adapter.Sections; s++)
{
if (HasSectionHeader)
{
if (position == linear)
{
return(SectionHeaderTemplateSelector?.SelectGroupTemplate(adapter, s)
?? SectionHeaderTemplate);
}
linear++;
}
var itemsInSection = adapter.ItemsForSection(s);
// It's an item in the section, return it for this item
if (position < linear + itemsInSection)
{
var itemIndex = position - linear;
return(ItemTemplateSelector?.SelectItemTemplate(adapter, s, itemIndex) ?? ItemTemplate);
}
linear += itemsInSection;
if (HasSectionFooter)
{
if (position == linear)
{
return(SectionFooterTemplateSelector?.SelectGroupTemplate(adapter, s)
?? SectionFooterTemplate);
}
linear++;
}
}
return(FooterTemplate);
}
public (DataTemplate template, PositionInfo info) GetTemplateAndInfo(IVirtualListViewAdapter adapter, int sectionIndex, int itemIndex)
{
var realSectionIndex = sectionIndex;
if (HasGlobalHeader)
{
if (sectionIndex == 0)
{
return(HeaderTemplate, new PositionInfo
{
Kind = PositionKind.Header
});
}
// Global header takes up a section, real adapter is 1 less
realSectionIndex--;
}
var realNumberOfSections = adapter.Sections;
if (HasGlobalFooter)
{
if (realSectionIndex >= realNumberOfSections)
{
return(FooterTemplate, new PositionInfo
{
Kind = PositionKind.Footer
});
}
}
var realItemsInSection = adapter.ItemsForSection(realSectionIndex);
var realItemIndex = itemIndex;
var itemsAdded = 0;
if (HasSectionHeader)
{
itemsAdded++;
realItemIndex--;
if (itemIndex == 0)
{
return(SectionHeaderTemplateSelector?.SelectGroupTemplate(adapter, realSectionIndex) ?? SectionHeaderTemplate,
new PositionInfo
{
Kind = PositionKind.SectionHeader,
ItemsInSection = realItemsInSection,
SectionIndex = realSectionIndex,
BindingContext = adapter.Section(realSectionIndex),
NumberOfSections = realNumberOfSections
});
}
}
if (HasSectionFooter)
{
itemsAdded++;
if (itemIndex >= realItemsInSection + itemsAdded - 1)
{
return(SectionFooterTemplateSelector?.SelectGroupTemplate(adapter, realSectionIndex) ?? SectionFooterTemplate,
new PositionInfo
{
Kind = PositionKind.SectionFooter,
ItemsInSection = realItemsInSection,
SectionIndex = realSectionIndex,
BindingContext = adapter.Section(realSectionIndex),
NumberOfSections = realNumberOfSections
});
}
}
return(ItemTemplateSelector?.SelectItemTemplate(adapter, realSectionIndex, realItemIndex) ?? ItemTemplate,
new PositionInfo
{
Kind = PositionKind.Item,
ItemsInSection = realItemsInSection,
SectionIndex = realSectionIndex,
ItemIndex = realItemIndex,
BindingContext = adapter.Item(realSectionIndex, realItemIndex),
NumberOfSections = realNumberOfSections,
});
}
public abstract DataTemplate SelectItemTemplate(IVirtualListViewAdapter adapter, int sectionIndex, int itemIndex);
public abstract DataTemplate SelectGroupTemplate(IVirtualListViewAdapter adapter, int sectionIndex);
public static object DataFor(this IVirtualListViewAdapter vlva, PositionKind kind, int sectionIndex, int itemIndex)
=> kind switch
{
