updated

Author: flocked

Example/Example/TableSidebarViewController.swift

@@ -85,28 +85,3 @@ class TableSidebarViewController: NSViewController {
         segmentedControl.selectedSegment = 0
     }
 }
-
-extension NSImage {
-    convenience init?(combining images: [NSImage]) {
-        guard !images.isEmpty else { return nil }
-        
-        let totalWidth = images.reduce(0) { $0 + $1.size.width }
-        let maxHeight = images.map { $0.size.height }.max() ?? 0
-        
-        let newSize = NSSize(width: totalWidth, height: maxHeight)
-        let newImage = NSImage(size: newSize)
-        
-        newImage.lockFocus()
-        
-        var xOffset: CGFloat = 0
-        for image in images {
-            let imageRect = NSRect(x: xOffset, y: maxHeight - image.size.height, width: image.size.width, height: image.size.height)
-            image.draw(in: imageRect)
-            xOffset += image.size.width
-        }
-        
-        newImage.unlockFocus()
-        
-        self.init(data: newImage.tiffRepresentation!)
-    }
-}

Sources/AdvancedCollectionTableView/DiffableDataSource/NSCollectionView/CollectionViewDiffableDataSource.swift

@@ -245,33 +245,27 @@ open class CollectionViewDiffableDataSource<Section: Identifiable & Hashable, El
         updateEmptyView(previousIsEmpty: previousIsEmpty)
     }
 
-    public enum PreviewImageSizing {
-        case size(CGSize)
-        case automatic
-        case fitting(width: CGFloat?, height: CGFloat?)
-    }
-    
     /// Returns a preview image of the collection view item for the specified element.
     public func previewImage(for element: Element) -> NSImage? {
-        previewImage(for: element, size: nil)
+        _previewImage(for: element, size: nil)
     }
 
     /// Returns a preview image of the collection view item for the specified element and item size.
     public func previewImage(for element: Element, size: CGSize) -> NSImage? {
-        previewImage(for: element, size: size)
+        _previewImage(for: element, size: size)
     }
 
     /// Returns a preview image of the collection view item for the specified element and item width.
     public func previewImage(for element: Element, width: CGFloat) -> NSImage? {
-        previewImage(for: element, width: width)
+        _previewImage(for: element, width: width)
     }
 
     /// Returns a preview image of the collection view item for the specified element and item height.
     public func previewImage(for element: Element, height: CGFloat) -> NSImage? {
-        previewImage(for: element, height: height)
+        _previewImage(for: element, height: height)
     }
 
-    private func previewImage(for element: Element, size: CGSize? = nil, width: CGFloat? = nil, height: CGFloat? = nil) -> NSImage? {
+    private func _previewImage(for element: Element, size: CGSize? = nil, width: CGFloat? = nil, height: CGFloat? = nil) -> NSImage? {
         guard let item = itemProvider(collectionView, IndexPath(item: 0, section: 0), element) else { return nil }
         if width != nil || height != nil {
             item.view.frame.size = item.view.systemLayoutSizeFitting(width: width, height: height)

Sources/AdvancedCollectionTableView/DiffableDataSource/NSOutlineView/OutlineViewDiffableDataSource.swift

@@ -502,14 +502,19 @@ public class OutlineViewDiffableDataSource<ItemIdentifierType: Hashable>: NSObje
     public func previewImage(for item: ItemIdentifierType) -> NSImage? {
         let columns = outlineView.tableColumns
         guard !columns.isEmpty else { return nil }
-        return NSImage(combining: columns.compactMap({ previewImage(for: item, tableColumn: $0, useColumnWidth: $0 !== columns.last!) }))
+        return NSImage(combineHorizontal: columns.compactMap({ previewImage(for: item, tableColumn: $0, useColumnWidth: $0 !== columns.last!) }), alignment: .top)
     }
 
     /// Returns a preview image of the table cell for the specified item and table column.
     public func previewImage(for item: ItemIdentifierType, tableColumn: NSTableColumn) -> NSImage? {
         previewImage(for: item, tableColumn: tableColumn, useColumnWidth: true)
     }
 
+    /// Returns a preview image of the table row for the specified items.
+    public func previewImage(for items: [ItemIdentifierType]) -> NSImage? {
+        NSImage(combineVertical: items.compactMap({ previewImage(for: $0)}).reversed(), alignment: .left)
+    }
+    
     private func previewImage(for item: ItemIdentifierType, tableColumn: NSTableColumn, useColumnWidth: Bool) -> NSImage? {
         guard let index = outlineView.tableColumns.firstIndex(of: tableColumn) else { return nil }
         let view = cellProvider(outlineView, tableColumn, item)

Sources/AdvancedCollectionTableView/DiffableDataSource/NSTableView/TableViewDiffableDataSource.swift

@@ -320,14 +320,19 @@ open class TableViewDiffableDataSource<Section, Item>: NSObject, NSTableViewData
     public func previewImage(for item: Item) -> NSImage? {
         let columns = tableView.tableColumns
         guard !columns.isEmpty else { return nil }
-        return NSImage(combining: columns.compactMap({ previewImage(for: item, tableColumn: $0, useColumnWidth: $0 !== columns.last!) }))
+        return NSImage(combineHorizontal: columns.compactMap({ previewImage(for: item, tableColumn: $0, useColumnWidth: $0 !== columns.last!) }), alignment: .top)
     }
 
     /// Returns a preview image of the table cell for the specified item and table column.
     public func previewImage(for item: Item, tableColumn: NSTableColumn) -> NSImage? {
         previewImage(for: item, tableColumn: tableColumn, useColumnWidth: true)
     }
 
+    /// Returns a preview image of the table row for the specified items.
+    public func previewImage(for items: [Item]) -> NSImage? {
+        NSImage(combineVertical: items.compactMap({ previewImage(for: $0)}).reversed(), alignment: .left)
+    }
+    
     private func previewImage(for item: Item, tableColumn: NSTableColumn, useColumnWidth: Bool) -> NSImage? {
         guard let index = tableView.tableColumns.firstIndex(of: tableColumn) else { return nil }
         let view = cellProvider(tableView, tableColumn, 0, item)

Sources/AdvancedCollectionTableView/Extensions/NSTableView/NSTableViewDiffableDataSource+.swift

@@ -83,7 +83,7 @@ public extension NSTableViewDiffableDataSource {
     private func previewImage(for item: ItemIdentifierType, tableView: NSTableView) -> NSImage? {
         let columns = tableView.tableColumns
         guard !columns.isEmpty else { return nil }
-        return NSImage(combining: columns.compactMap({ _previewImage(for: item, tableColumn: $0, tableView: tableView, useColumnWidth: $0 !== columns.last!) }))
+        return NSImage(combineHorizontal: columns.compactMap({ _previewImage(for: item, tableColumn: $0, tableView: tableView, useColumnWidth: $0 !== columns.last!) }), alignment: .top)
     }
 
     private func previewImage(for item: ItemIdentifierType, tableColumn: NSTableColumn, tableView: NSTableView) -> NSImage? {
@@ -103,28 +103,3 @@ public extension NSTableViewDiffableDataSource {
         return view.renderedImage
     }
 }
-
-extension NSImage {
-    convenience init?(combining images: [NSImage]) {
-        guard !images.isEmpty else { return nil }
-        
-        let totalWidth = images.reduce(0) { $0 + $1.size.width }
-        let maxHeight = images.map { $0.size.height }.max() ?? 0
-        
-        let newSize = NSSize(width: totalWidth, height: maxHeight)
-        let newImage = NSImage(size: newSize)
-        
-        newImage.lockFocus()
-        
-        var xOffset: CGFloat = 0
-        for image in images {
-            let imageRect = NSRect(x: xOffset, y: maxHeight - image.size.height, width: image.size.width, height: image.size.height)
-            image.draw(in: imageRect)
-            xOffset += image.size.width
-        }
-        
-        newImage.unlockFocus()
-        
-        self.init(data: newImage.tiffRepresentation!)
-    }
-}