private void ConfigureDataSource()
{
var dataSource = new UICollectionViewDiffableDataSource <NS <Section>, NS <int> >(
collectionView: _collectionView,
cellProvider: (collectionView, indexPath, identifier) =>
{
var cell = (DummyCell)collectionView.DequeueReusableCell(DummyCell.Key, indexPath);
cell.Configure(((NS <int>)identifier).Value.ToString());
return(cell);
});
// initial data
const int ItemsPerSection = 6;
var snapshot = new NSDiffableDataSourceSnapshot <NS <Section>, NS <int> >();
EnumExtensions.Apply <Section>(section =>
{
var ns = new NS <Section>(section);
snapshot.AppendSections(new[] { ns });
var itemOffset = ((int)ns.Value) * ItemsPerSection;
var itemUpperbound = itemOffset + ItemsPerSection;
var items = Enumerable.Range(itemOffset, itemUpperbound).Select(x => new NS <int>(x)).ToArray();
snapshot.AppendItems(items);
});
dataSource.ApplySnapshot(snapshot, animatingDifferences: false);
}
public void ObjectUsageTest()
{
var diff = new NSDiffableDataSourceSnapshot <NSNumber, NSUuid> ();
diff.AppendSections(new NSNumber [] { NSNumber.FromNInt(1) });
diff.AppendItems(new NSUuid [] { new NSUuid() }, NSNumber.FromNInt(1));
Assert.That(diff.NumberOfSections, Is.GreaterThan((nint)0), "Sections");
Assert.That(diff.GetNumberOfItems(NSNumber.FromNInt(1)), Is.GreaterThan((nint)0), "Items");
}
void ConfigureDataSource()
{
dataSource = new UICollectionViewDiffableDataSource <NSNumber, NSNumber> (collectionView, CellProviderHandler)
{
SupplementaryViewProvider = SupplementaryViewProviderHandler
};
// initial data
var snapshot = new NSDiffableDataSourceSnapshot <NSNumber, NSNumber> ();
var idOffset = 0;
var itemsPerSection = 18;
foreach (var section in SectionKind.AllSections)
{
snapshot.AppendSections(new [] { NSNumber.FromInt32(section.EnumValue) });
var items = Enumerable.Range(idOffset, itemsPerSection).Select(i => NSNumber.FromInt32(i)).ToArray();
snapshot.AppendItems(items);
idOffset += itemsPerSection;
}
dataSource.ApplySnapshot(snapshot, false);
UICollectionViewCell CellProviderHandler(UICollectionView collectionView, NSIndexPath indexPath, NSObject obj)
{
// Get a cell of the desired kind.
var cell = collectionView.DequeueReusableCell(TextCell.Key, indexPath) as TextCell;
// Populate the cell with our item description.
cell.Label.Text = $"{indexPath.Section}, {indexPath.Row}";
cell.ContentView.BackgroundColor = UIColorExtensions.CornflowerBlue;
cell.ContentView.Layer.BorderColor = UIColor.Black.CGColor;
cell.ContentView.Layer.BorderWidth = 1;
cell.ContentView.Layer.CornerRadius = 8;
cell.Label.TextAlignment = UITextAlignment.Center;
cell.Label.Font = UIFont.GetPreferredFontForTextStyle(UIFontTextStyle.Title1);
// Return the cell.
return(cell);
}
UICollectionReusableView SupplementaryViewProviderHandler(UICollectionView collectionView, string kind, NSIndexPath indexPath)
{
var sectionKind = SectionKind.GetSectionKind(indexPath.Section);
// Get a supplementary view of the desired kind.
var header = collectionView.DequeueReusableSupplementaryView(new NSString(kind),
TitleSupplementaryView.Key, indexPath) as TitleSupplementaryView;
// Populate the view with our section's description.
header.Label.Text = $".{sectionKind}";
// Return the view.
return(header);
}
}
void ConfigureDataSource()
{
dataSource = new UICollectionViewDiffableDataSource <NSNumber, NSNumber> (collectionView, CellProviderHandler)
{
SupplementaryViewProvider = SupplementaryViewProviderHandler
};
// initial data
var itemsPerSection = 5;
var sections = Enumerable.Range(0, 5).Select(i => NSNumber.FromInt32(i)).ToArray();
var snapshot = new NSDiffableDataSourceSnapshot <NSNumber, NSNumber> ();
var itemOffset = 0;
foreach (var section in sections)
{
snapshot.AppendSections(new [] { section });
var items = Enumerable.Range(itemOffset, itemsPerSection).Select(i => NSNumber.FromInt32(i)).ToArray();
snapshot.AppendItems(items);
itemOffset += itemsPerSection;
}
dataSource.ApplySnapshot(snapshot, false);
UICollectionViewCell CellProviderHandler(UICollectionView collectionView, NSIndexPath indexPath, NSObject obj)
{
// Get a cell of the desired kind.
var cell = collectionView.DequeueReusableCell(ListCell.Key, indexPath) as ListCell;
// Populate the cell with our item description.
cell.Label.Text = $"{indexPath.Section}, {indexPath.Row}";
// Return the cell.
return(cell);
}
UICollectionReusableView SupplementaryViewProviderHandler(UICollectionView collectionView, string kind, NSIndexPath indexPath)
{
// Get a supplementary view of the desired kind.
var supplementaryView = collectionView.DequeueReusableSupplementaryView(new NSString(kind),
TitleSupplementaryView.Key, indexPath) as TitleSupplementaryView;
// Populate the view with our section's description.
var viewKind = kind == sectionHeaderElementKind ? "Header" : "Footer";
supplementaryView.Label.Text = $"{viewKind} for section {indexPath.Section}";
supplementaryView.BackgroundColor = UIColor.LightGray;
supplementaryView.Layer.BorderColor = UIColor.Black.CGColor;
supplementaryView.Layer.BorderWidth = 1;
// Return the view.
return(supplementaryView);
}
}
NSDiffableDataSourceSnapshot <InsertionSortArray, InsertionSortArray.SortNode> RandomizedSnapshot(CGRect bounds)
{
var snapshot = new NSDiffableDataSourceSnapshot <InsertionSortArray, InsertionSortArray.SortNode> ();
var rowCount = GetRows(bounds);
var columnCount = GetColumns(bounds);
for (int i = 0; i < rowCount; i++)
{
var section = new InsertionSortArray(columnCount);
snapshot.AppendSections(new [] { section });
snapshot.AppendItems(section.Nodes);
}
return(snapshot);
}
ToDiffableDataSourceSnapshot <TSection, TItem>(this Dictionary <TSection, List <TItem> > dict)
{
var snapshot = new NSDiffableDataSourceSnapshot <IdentifierType <TSection>, IdentifierType <TItem> >();
foreach (var kvp in dict)
{
var section = IdentifierType.For(kvp.Key);
var items = kvp.Value.Select(IdentifierType.For).ToArray();
snapshot.AppendSections(new[] { section });
snapshot.AppendItems(items);
}
return(snapshot);
}
void ConfigureDataSource()
{
dataSource = new UICollectionViewDiffableDataSource <ConferenceVideoController.VideoCollection, ConferenceVideoController.Video> (collectionView, CellProviderHandler)
{
SupplementaryViewProvider = SupplementaryViewProviderHandler
};
currentSnapshot = new NSDiffableDataSourceSnapshot <ConferenceVideoController.VideoCollection, ConferenceVideoController.Video> ();
foreach (var videoCollection in videosController.Collections)
{
currentSnapshot.AppendSections(new [] { videoCollection });
currentSnapshot.AppendItems(videoCollection.Videos);
}
dataSource.ApplySnapshot(currentSnapshot, false);
UICollectionViewCell CellProviderHandler(UICollectionView collectionView, NSIndexPath indexPath, NSObject obj)
{
var video = obj as ConferenceVideoController.Video;
// Get a cell of the desired kind.
var cell = collectionView.DequeueReusableCell(ConferenceVideoCell.Key, indexPath) as ConferenceVideoCell;
// Populate the cell with our item description.
cell.TitleLabel.Text = video.Title;
cell.CategoryLabel.Text = video.Category;
// Return the cell.
return(cell);
}
UICollectionReusableView SupplementaryViewProviderHandler(UICollectionView collectionView, string kind, NSIndexPath indexPath)
{
// Get a supplementary view of the desired kind.
var titleSupplementary = collectionView.DequeueReusableSupplementaryView(new NSString(kind),
TitleSupplementaryView.Key, indexPath) as TitleSupplementaryView;
// Populate the view with our section's description.
var videoCategory = currentSnapshot.SectionIdentifiers [indexPath.Section];
titleSupplementary.Label.Text = videoCategory.Title;
// Return the view.
return(titleSupplementary);
}
}
NSDiffableDataSourceSnapshot <Section, MountainsController.Mountain> InitialSnapshot()
{
var mountainsController = new MountainsController();
var limit = 8;
var mountains = mountainsController.FilterMountains(limit: limit);
var bucketList = mountains.Take(limit / 2).ToArray();
var visited = mountains.Skip(limit / 2).Take(limit / 2).ToArray();
var snapshot = new NSDiffableDataSourceSnapshot <Section, MountainsController.Mountain> ();
snapshot.AppendSections(new [] { Section.Visited });
snapshot.AppendItems(visited);
snapshot.AppendSections(new [] { Section.BucketList });
snapshot.AppendItems(bucketList);
return(snapshot);
}
ToDiffableDataSourceSnapshot <TSection, TSectionIdentifier, TItem, TItemIdentifier>(
this IEnumerable <TSection> sections, Func <TSection, TSectionIdentifier> getSectionIdentifier,
Func <TSection, IEnumerable <TItem> > getItems, Func <TItem, TItemIdentifier> getItemIdentifier)
{
var snapshot = new NSDiffableDataSourceSnapshot <IdentifierType <TSection>, IdentifierType <TItem> >();
foreach (var section in sections)
{
var items = getItems(section);
var sectionIdentifier = IdentifierType.For(section, getSectionIdentifier);
var itemIdentifiers = items.Select(item => IdentifierType.For(item, getItemIdentifier)).ToArray();
snapshot.AppendSections(new[] { sectionIdentifier });
snapshot.AppendItems(itemIdentifiers);
}
return(snapshot);
}
private void ConfigureDataSource()
{
var dataSource = new UICollectionViewDiffableDataSource <NS <Section>, NS <int> >(
collectionView: _collectionView,
cellProvider: (collectionView, indexPath, identifier) =>
{
var cell = (DummyCell)collectionView.DequeueReusableCell(DummyCell.Key, indexPath);
cell.Configure(((NS <int>)identifier).Value.ToString());
return(cell);
});
// initial data
var snapshot = new NSDiffableDataSourceSnapshot <NS <Section>, NS <int> >();
snapshot.AppendSections(new[] { new NS <Section>(Section.Main) });
snapshot.AppendItems(Enumerable.Range(0, 100).Select(x => new NS <int>(x)).ToArray());
dataSource.ApplySnapshot(snapshot, animatingDifferences: false);
}
ToDiffableDataSourceSnapshot <TObject, TSection, TItem>(
this TObject obj,
Func <TObject, IEnumerable <TSection> > getSections,
Func <TSection, IEnumerable <TItem> > getItems)
{
var snapshot = new NSDiffableDataSourceSnapshot <IdentifierType <TSection>, IdentifierType <TItem> >();
foreach (var section in getSections(obj))
{
var items = getItems(section);
var sectionIdentifier = IdentifierType.For(section);
var itemIdentifiers = items.Select(IdentifierType.For).ToArray();
snapshot.AppendSections(new[] { sectionIdentifier });
snapshot.AppendItems(itemIdentifiers);
}
return(snapshot);
}
void ConfigureDataSource()
{
dataSource = new UICollectionViewDiffableDataSource <NSNumber, NSNumber> (collectionView, CellProviderHandler);
// initial data
var itemsPerSection = 5;
var sections = Enumerable.Range(0, 5).Select(i => NSNumber.FromInt32(i)).ToArray();
currentSnapshot = new NSDiffableDataSourceSnapshot <NSNumber, NSNumber> ();
var itemOffset = 0;
foreach (var section in sections)
{
currentSnapshot.AppendSections(new [] { section });
var items = Enumerable.Range(itemOffset, itemsPerSection).Select(i => NSNumber.FromInt32(i)).ToArray();
currentSnapshot.AppendItems(items);
itemOffset += itemsPerSection;
}
dataSource.ApplySnapshot(currentSnapshot, false);
UICollectionViewCell CellProviderHandler(UICollectionView collectionView, NSIndexPath indexPath, NSObject obj)
{
var sectionId = currentSnapshot.SectionIdentifiers [indexPath.Section];
var numberOfItemsInSection = currentSnapshot.GetNumberOfItems(sectionId);
var isLastCell = indexPath.Item + 1 == numberOfItemsInSection;
// Get a cell of the desired kind.
var cell = collectionView.DequeueReusableCell(ListCell.Key, indexPath) as ListCell;
// Populate the cell with our item description.
cell.Label.Text = $"{indexPath.Section}, {indexPath.Row}";
cell.SeparatorView.Hidden = isLastCell;
// Return the cell.
return(cell);
}
}
public static BetterUITableViewDiffableDataSource <TSection, TItem> Create <TSection, TItem>(
UITableView tableView,
NSDiffableDataSourceSnapshot <IdentifierType <TSection>, IdentifierType <TItem> > snapshot,
Func <UITableView, NSIndexPath, TItem, UITableViewCell> getCell) => new BetterUITableViewDiffableDataSource <TSection, TItem>(tableView,
(tv, indexPath, rawIdentifier) => getCell(tv, indexPath, ((IdentifierType <TItem>)rawIdentifier).Item));
