void CenterAlignCellsInColumn(UICollectionViewLayoutAttributes preferredAttributes)
{
// Determine the set of cells above this one
var index = preferredAttributes.IndexPath;
var span = _itemsLayout.Span;
var column = index.Item / span;
var start = (int)column * span;
// If this is the first cell in the column, we don't need to adjust
if (index.Item > start)
{
var currentCenter = preferredAttributes.Frame.GetMidX();
// Work our way through the column
for (int n = start; n < index.Item; n++)
{
// Get the layout attributes for each cell
var path = NSIndexPath.FromItemSection(n, index.Section);
var attr = LayoutAttributesForItem(path);
// And see if the midpoints line up with the new layout attributes for the current cell
var center = attr.Frame.GetMidX();
if (currentCenter - center > 1)
{
// If the midpoints don't line up (withing a tolerance), adjust the cell's frame
var cell = CollectionView.CellForItem(path);
cell.Frame = new CGRect(currentCenter - cell.Frame.Width / 2, cell.Frame.Top, cell.Frame.Width, cell.Frame.Height);
}
}
}
}
private void panBegan(CGPoint point)
{
if (!isActive)
{
return;
}
allItemsStartAndEndTime = dataSource.AllItemsStartAndEndTime();
firstPoint = point;
LastPoint = point;
var cell = CollectionView.CellForItem(itemIndexPath) as CalendarItemView;
var topDragRect = CollectionView.ConvertRectFromView(cell.TopDragTouchArea, cell);
var bottomDragRect = CollectionView.ConvertRectFromView(cell.BottomDragTouchArea, cell);
if (topDragRect.Contains(point))
{
action = EditAction.ChangeStartTime;
}
else if (bottomDragRect.Contains(point))
{
action = EditAction.ChangeEndTime;
}
else if (cell.Frame.Contains(point))
{
action = EditAction.ChangeOffset;
}
else
{
action = EditAction.None;
}
selectionFeedback.Prepare();
}
public override void ItemDeselected(UICollectionView collectionView, NSIndexPath indexPath)
{
if (CollectionView.CellForItem(indexPath) is ShellSectionHeaderCell cell)
{
cell.Label.TextColor = _unselectedColor.ToUIColor();
}
}
private void HandleHeaderTapGesture(NSObject obj)
{
if (obj is UITapGestureRecognizer gesture)
{
if (gesture.View is SelectableDateCollectionHeaderView header)
{
var section = GetSectionFromDateTime(header.DateTime);
int sectionIndex = Sections.IndexOf(section);
bool isSectionSelected = section.Selected;
for (int i = 0; i < section.Images.Count; ++i)
{
if (CollectionView.CellForItem(NSIndexPath.FromItemSection(i, sectionIndex)) is SelectableImageCollectionViewCell cell)
{
if (isSectionSelected)
{
UnselectImage(cell.Image.Asset, sectionIndex);
cell.UpdateSelectedState(false, true);
continue;
}
if (!SelectedImages.Contains(cell.Image.Asset))
{
if (SelectImageIfPossible(cell.Image.Asset, sectionIndex))
{
cell.UpdateSelectedState(true, true);
}
}
}
}
}
}
}
public override void SetEditing(bool editing, bool animated)
{
base.SetEditing(editing, animated);
addButton.Enabled = !editing;
deleteButton.Enabled = editing;
CollectionView.AllowsMultipleSelection = editing;
// Make Sure For VisibleItems Not SelectedItems!
var indexes = CollectionView.IndexPathsForVisibleItems;
foreach (var index in indexes)
{
var cell = CollectionView.CellForItem(index) as CollectionViewCell;
cell.Editing = editing;
}
if (!editing)
{
NavigationController.ToolbarHidden = true;
}
else
{
NavigationController.ToolbarHidden = false;
}
}
UIDragPreviewParameters PreviewParameters(NSIndexPath indexPath)
{
var cell = CollectionView.CellForItem(indexPath) as PhotoCollectionViewCell;
var previewParameters = new UIDragPreviewParameters();
previewParameters.VisiblePath = UIBezierPath.FromRect(cell.ClippingRectForPhoto);
return(previewParameters);
}
private void stopEditingCurrentCellIfNotVisible()
{
var cellNotVisible = CollectionView.CellForItem(itemIndexPath) == null;
if (cellNotVisible)
{
stopEditingCurrentCell();
}
}
public void SetVisiblePercent(nfloat percent)
{
if (CollectionView.IndexPathsForVisibleItems.Length == 0)
{
return;
}
var path = CollectionView.IndexPathsForVisibleItems[0];
var cell = CollectionView.CellForItem(path) as CurrentSongCollectionViewCell;
cell?.UpdatePercent(percent);
}
InkView GetInkViewAtTouchLocation(InkTouchController inkTouchController, CGPoint location)
{
var indexPath = CollectionView.IndexPathForItemAtPoint(location);
if (indexPath == null)
{
return(new InkView());
}
var cell = CollectionView.CellForItem(indexPath);
return(GetInkView(cell));
}
public override void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)
{
var row = indexPath.Row;
var item = ShellSection.Items[row];
if (item != ShellSection.CurrentItem)
{
ShellSection.SetValueFromRenderer(ShellSection.CurrentItemProperty, item);
}
var cell = (ShellSectionHeaderCell)CollectionView.CellForItem(indexPath);
cell.Label.TextColor = _selectedColor.ToUIColor();
}
public override void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)
{
var row = indexPath.Row;
var item = ShellSectionController.GetItems()[row];
if (item != ShellSection.CurrentItem)
{
ShellSection.SetValueFromRenderer(ShellSection.CurrentItemProperty, item);
}
if (CollectionView.CellForItem(indexPath) is ShellSectionHeaderCell cell)
{
cell.Label.TextColor = _selectedColor.ToPlatform();
}
}
public override void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)
{
base.ItemSelected(collectionView, indexPath);
_manuallySelected = true;
SelectedIndex = indexPath.Row;
UIView.AnimateNotify(0.3f, () =>
{
var cell = CollectionView.CellForItem(indexPath);
_tabIndicator.Frame = new CGRect(cell.Frame.Left, 0, cell.Frame.Width, 2);
}, (finished) =>
{
_manuallySelected = false;
});
}
public override void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
// Update the selection UI
int index = Array.FindIndex(availableFilterInfos, fInfo => fInfo.FilterName == selectedFilterName);
if (index < 0)
{
return;
}
NSIndexPath indexPath = NSIndexPath.FromItemSection(index, 0);
CollectionView.SelectItem(indexPath, false, UICollectionViewScrollPosition.CenteredHorizontally);
UpdateSelectionForCell(CollectionView.CellForItem(indexPath));
}
public override async void ViewDidAppear(bool animated)
{
isVisible = true;
base.ViewDidAppear(animated);
await Task.Delay(50);
scrollTocurrentSong();
await Task.Delay(50);
if (CollectionView.IndexPathsForVisibleItems.Length == 0)
{
return;
}
var path = CollectionView.IndexPathsForVisibleItems[0];
var cell = CollectionView.CellForItem(path) as CurrentSongCollectionViewCell;
cell?.SetNeedsLayout();
}
public override void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)
{
coolTransitioningDelegate = coolTransitioningDelegate ?? new CoolTransitioningDelegate();
overlayTransitioningDelegate = overlayTransitioningDelegate ?? new OverlayTransitioningDelegate();
overlay = overlay ?? new OverlayViewController();
if (PresentationShouldBeAwesome)
{
overlay.TransitioningDelegate = coolTransitioningDelegate;
}
else
{
overlay.TransitioningDelegate = overlayTransitioningDelegate;
}
overlay.PhotoView = (PhotoCollectionViewCell)CollectionView.CellForItem(indexPath);
PresentViewController(overlay, true, null);
}
public override void ReloadData()
{
if (ItemsSource != null && (ItemsSource as IList).Count > 0 && ((ItemsSource as IList).Count != CollectionView.NumberOfItemsInSection(0) || !CollectionView.VisibleCells.Any()))
{
CollectionView.PerformBatchUpdates(() =>
{
var newItems = ItemsSource as IList;
if (newItems != null)
{
var indexes = new NSIndexPath[newItems.Count];
var startIndex = ItemsSource == null ? 0 : ItemsSource.Count() - newItems.Count;
for (var i = 0; i < indexes.Length; i++)
{
indexes[i] = NSIndexPath.FromRowSection(startIndex + i, 0);
}
if (CollectionView.VisibleCells.Any())
{
CollectionView.ReloadItems(indexes);
}
else
{
CollectionView.InsertItems(indexes);
}
}
else
{
ReloadData();
}
}, ok =>
{
var path = NSIndexPath.FromRowSection(_selectedIndex, 0);
CollectionView.SelectItem(path, false, UICollectionViewScrollPosition.CenteredHorizontally);
var cell = CollectionView.CellForItem(path);
if (cell != null)
{
_tabIndicator.Frame = new CGRect(cell.Frame.Left, 0, cell.Frame.Width, 2);
}
});
}
}
public virtual void OnExternalScroll(UIScrollView scrollView)
{
if (_manuallySelected)
{
return;
}
var contentOffset = scrollView.ContentOffset;
var delta = (contentOffset.X - scrollView.Bounds.Width) / scrollView.Bounds.Width;
var currentCell = CollectionView.CellForItem(NSIndexPath.FromRowSection(SelectedIndex, 0));
if (currentCell != null)
{
var currentIndicatorX = currentCell.Frame.Left;
var nextCellIndex = SelectedIndex + (delta > 0 ? 1 : -1);
if (nextCellIndex >= 0 && nextCellIndex < (ItemsSource as IList).Count)
{
var nextCell = CollectionView.CellForItem(NSIndexPath.FromRowSection(nextCellIndex, 0));
if (nextCell != null)
{
var nextIndicatorX = nextCell.Frame.Left;
var distance = (nextIndicatorX - currentIndicatorX) * delta;
var widthDifference = nextCell.Frame.Width - currentCell.Frame.Width;
_tabIndicator.Frame = new CGRect(
currentCell.Frame.Left + (delta > 0 ? distance : -distance),
0,
currentCell.Frame.Width + widthDifference * Math.Abs(delta),
2
);
}
}
}
}
internal void SelectPuzzleManually(PuzzleData selectedPuzzle)
{
int index = -1;
int section = -1;
if (puzzlesPxn.Contains(selectedPuzzle))
{
section = 0;
index = puzzlesPxn.IndexOf(selectedPuzzle);
}
else if (puzzlesCustom.Contains(selectedPuzzle))
{
section = 1;
index = puzzlesCustom.IndexOf(selectedPuzzle);
}
NSIndexPath path = NSIndexPath.FromItemSection(index, section);
var cell = CollectionView.CellForItem(path) as PuzzlesListCellViewController;
cell.SetSelected();
lastSelectedCell = cell;
}
public UIViewController GetViewControllerForPreview(IUIViewControllerPreviewing previewingContext, CGPoint location)
{
// Obtain the index path and the cell that was pressed.
var indexPath = CollectionView.IndexPathForItemAtPoint(location);
Console.WriteLine("ForPreview " + location.ToString() + " " + indexPath);
if (indexPath == null)
{
return(null);
}
var cell = CollectionView.CellForItem(indexPath);
if (cell == null)
{
return(null);
}
// Create a detail view controller and set its properties.
var peekViewController = (PeekViewController)Storyboard.InstantiateViewController("peekvc");
if (peekViewController == null)
{
return(null);
}
var peekAt = todoItems [indexPath.Row];
peekViewController.SetTodo(peekAt);
peekViewController.PreferredContentSize = new CGSize(0, 160);
previewingContext.SourceRect = cell.Frame;
return(peekViewController);
}
protected override void HandleLongPressGesture()
{
switch (LongPressGestureRecognizer.State)
{
case UIGestureRecognizerState.Began:
{
// we get the current item and draw a floating copy on it on the Collection View, so that it cannot be taken outside the bounds of the collection view
// we get the copy usign RasterizedImage
var currentIndexPath = CollectionView.IndexPathForItemAtPoint(LongPressGestureRecognizer.LocationInView(CollectionView));
SelectedItemIndexPath = currentIndexPath;
if (SelectedItemIndexPath == null)
{
return;
}
if (!DataSource.CanMoveItemAtIndexPath(SelectedItemIndexPath))
{
return;
}
var collectionViewCell = CollectionView.CellForItem(SelectedItemIndexPath);
CurrentView = new UIView(collectionViewCell.Frame);
collectionViewCell.Highlighted = true;
var highlightedImageView = new UIImageView(RastertizedImage(collectionViewCell));
highlightedImageView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
highlightedImageView.Alpha = 1.0f;
collectionViewCell.Highlighted = false;
var imageView = new UIImageView(RastertizedImage(collectionViewCell));
imageView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
imageView.Alpha = 0.0f;
CurrentView.AddSubview(imageView);
CurrentView.AddSubview(highlightedImageView);
CollectionView.AddSubview(CurrentView);
CurrentViewCenter = CurrentView.Center;
OnWillBeginDraggingItem(SelectedItemIndexPath);
// animate the floating copy into existence
UIView.Animate(0.3, 0.0, UIViewAnimationOptions.BeginFromCurrentState,
() =>
{
CurrentView.Transform = CGAffineTransform.MakeScale(1.1f, 1.1f);
highlightedImageView.Alpha = 0.0f;
imageView.Alpha = 1.0f;
},
() =>
{
highlightedImageView.RemoveFromSuperview();
OnDidBegingDraggingItem(SelectedItemIndexPath);
});
InvalidateLayout();
}
break;
case UIGestureRecognizerState.Cancelled:
case UIGestureRecognizerState.Ended:
{
var currentIndexPath = SelectedItemIndexPath;
if (currentIndexPath == null)
{
return;
}
SelectedItemIndexPath = null;
CurrentViewCenter = PointF.Empty;
OnWillEndDraggingItem(currentIndexPath);
UIView.Animate(0.3, 0.0, UIViewAnimationOptions.BeginFromCurrentState,
() =>
{
var layoutAttributes = LayoutAttributesForItem(currentIndexPath);
CurrentView.Transform = CGAffineTransform.MakeScale(1.0f, 1.0f);
CurrentView.Center = layoutAttributes.Center;
},
() =>
{
CurrentView.RemoveFromSuperview();
CurrentView = null;
InvalidateLayout();
OnDidEndDraggingItem(currentIndexPath);
});
}
break;
}
}
protected override void HandleLongPressGesture()
{
switch (LongPressGestureRecognizer.State)
{
case UIGestureRecognizerState.Began:
{
// we try to grab the current seelected item and draw a floating copy of it on the Drag Surface
// the copy is just an image of it using RasterizedImage
var currentIndexPath = CollectionView.IndexPathForItemAtPoint(LongPressGestureRecognizer.LocationInView(CollectionView));
SelectedItemIndexPath = currentIndexPath;
if (SelectedItemIndexPath == null)
{
return;
}
if (!DataSource.CanMoveItemAtIndexPath(SelectedItemIndexPath))
{
return;
}
var collectionViewCell = CollectionView.CellForItem(SelectedItemIndexPath);
var tpoint = DragSurface.ConvertPointFromView(collectionViewCell.Frame.Location, CollectionView);
RectangleF frame = new RectangleF(tpoint.X, tpoint.Y, collectionViewCell.Frame.Size.Width, collectionViewCell.Frame.Size.Height);
CurrentView = new UIView(frame);
collectionViewCell.Highlighted = true;
var highlightedImageView = new UIImageView(RastertizedImage(collectionViewCell));
highlightedImageView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
highlightedImageView.Alpha = 1.0f;
collectionViewCell.Highlighted = false;
var imageView = new UIImageView(RastertizedImage(collectionViewCell));
imageView.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
imageView.Alpha = 0.0f;
CurrentView.AddSubview(imageView);
CurrentView.AddSubview(highlightedImageView);
DragSurface.AddSubview(CurrentView); // add this to the top level view so that we can drag outside
CurrentViewCenter = CurrentView.Center;
OnWillBeginDraggingItem(SelectedItemIndexPath);
// we animate the drawing out of the floating copy
UIView.Animate(0.3, 0.0, UIViewAnimationOptions.BeginFromCurrentState,
() =>
{
CurrentView.Transform = CGAffineTransform.MakeScale(1.1f, 1.1f);
highlightedImageView.Alpha = 0.0f;
imageView.Alpha = 1.0f;
},
() =>
{
highlightedImageView.RemoveFromSuperview();
OnDidBegingDraggingItem(SelectedItemIndexPath);
});
InvalidateLayout();
}
break;
case UIGestureRecognizerState.Cancelled:
case UIGestureRecognizerState.Ended:
{
var currentIndexPath = SelectedItemIndexPath;
if (currentIndexPath == null || CurrentView == null)
{
return;
}
SelectedItemIndexPath = null;
CurrentViewCenter = PointF.Empty;
OnWillEndDraggingItem(currentIndexPath);
UIView.Animate(0.3, 0.0, UIViewAnimationOptions.BeginFromCurrentState,
() =>
{
var layoutAttributes = this.LayoutAttributesForItem(currentIndexPath);
CurrentView.Transform = CGAffineTransform.MakeScale(1.0f, 1.0f);
CurrentView.Center = CollectionView.ConvertPointToView(layoutAttributes.Center, DragSurface);
},
() =>
{
CurrentView.RemoveFromSuperview();
CurrentView = null;
InvalidateLayout();
OnDidEndDraggingItem(currentIndexPath);
});
}
break;
}
}
public override void ItemHighlighted(UICollectionView collectionView, NSIndexPath indexPath)
{
var cell = CollectionView.CellForItem(indexPath);
cell.Alpha = (nfloat)0.6;
}