This is a NSCollectionView like class that works on Tiger. It derives directly from NSView. I tried to customize NSTableView but there were too many bugs with drag/drop and scrollbars for it too work. If you don’t need those features then you might want to start there first (see http://www.joar.com/code ). –SaileshAgrawal

This is written specifically with the requirements I had in mind. It has the following features and limitations hard coded into it:

• Like NSCollectionView allows you to create you row’s view in Interface Builder and add it to the collection view.
• One column only
• Always has at least one selected item.
• Allows multiple selection.
• Allows reordering of items using drag/drop.
• Allows files to be dragged into it.
• Allows rows to be dragged out of it as shortcuts to files.
• Automatically changes text field colors to white when a row is selected.
• Your row view must derive from TigerCollectionViewItem to be added to the collection view.
• Allows menus on right click

Remember that this is mostly sample code. Feel free to use it any way you like but there will likely be some bugs in it.

---

Interface

#import <Cocoa/Cocoa.h>

@class TigerCollectionViewItem;

@protocol TigerCollectionViewTarget

• (NSDragOperation)dragOperationForFiles: (NSArray *)filePaths;
• (void)dragFiles: (NSArray *)filePaths toIndex: (int)index;
• (void)dragItemsAtIndexes: (NSArray *)indexes toIndex: (int)index;
• (BOOL)shouldRemoveItemsAtIndexes: (NSArray *)indexes;
• (void)performDoubleClickActionForIndex: (int)index;
• (void)onSelectionDidChange;
• (NSString *)filePathForIndex: (int)index;

@end

@interface TigerCollectionView : NSView { IBOutlet id target; NSMutableArray *items; BOOL needsLayout; }

• (void)addItem: (TigerCollectionViewItem *)item atIndex: (int)index;

• (void)removeItemAtIndex: (int)index;

• (void)removeAllItems;

• (int)numberOfItems;

• (NSArray *)selectedIndexes;

@end

@interface TigerCollectionViewItem : NSView { BOOL isSelected; NSPoint mouseDownPos; int dragTargetType; NSMutableDictionary *cachedTextColors; } @end

---

Implementation

#import “TigerCollectionView.h”

static const float DRAG_START_DISTANCE = 10; static const float DRAG_IMAGE_ALPHA = 0.5; static NSString * const DRAG_ITEM_TYPE = @”TigerCollectionViewDragType”;

typedef enum { DragTargetType_None, DragTargetType_Top, DragTargetType_Bottom, } DragTargetType;

@interface TigerCollectionView (Private)

// Override NSView

• (void)moveDown: (id)sender;
• (void)moveUp: (id)sender;
• (BOOL)isFlipped;
• (void)selectAll: (id)sender;
• (void)keyDown: (NSEvent *)event;
• (void)deleteBackward: (id)sender;
• (void)deleteForward: (id)sender;
• (NSDragOperation)draggingEntered: (id)sender;
• (void)draggingExited: (id)sender;
• (BOOL)prepareForDragOperation: (id)sender;
• (BOOL)performDragOperation: (id)sender;
• (NSDragOperation)draggingUpdated: (id)sender;
• (BOOL)wantsPeriodicDraggingUpdates;
• (NSDragOperation)draggingSourceOperationMaskForLocal: (BOOL)isLocal;
• (void)resizeWithOldSuperviewSize: (NSSize)oldBoundsSize;

// Internal methods

• (void)setNeedsLayout: (BOOL)flag;
• (void)performLayout;
• (void)startDrag: (NSEvent *)event withItem: (TigerCollectionViewItem *)item;
• (NSImage *)dragImageForIndexes: (NSArray *)indexes dragPoint: (NSPoint *)dragPoint;
• (void)itemClicked: (TigerCollectionViewItem *)item event: (NSEvent *)event;
• (void)setAllItemsSelected: (BOOL)selected;
• (void)growSelectionToItem: (TigerCollectionViewItem *)item;
• (void)moveSelection: (BOOL)moveUp byExtending: (BOOL)byExtending;
• (void)scrollToItem: (TigerCollectionViewItem *)item;
• (void)maintainNonEmptySelection: (int)index;
• (void)removeItemsAtIndexes: (NSArray *)indexes;
• (int)indexFromDragTarget: (NSView *)targetView draggingInfo: (id)draggingInfo;
• (void)setDragTarget: (NSView *)targetView draggingInfo: (id)draggingInfo;
• (void)setIndex: (int)index isDragTarget: (BOOL)isDragTarget;
• (id)target;
• (int)dragTargetIndex;
• (void)maximizeViewWidth: (id)sender;
• (void)onKeyWindowChanged: (NSNotification *)notification;
• (void)testSelectionChanged: (NSArray *)oldSelection;
• (NSArray *)filePathsForIndexes: (NSArray *)indexes;

@end

@interface TigerCollectionViewItem (Private)

// Override NSView

• (NSMenu *)menuForEvent:(NSEvent *)event;
• (NSView *)hitTest: (NSPoint)point;
• (void)mouseDown: (NSEvent *)event;
• (void)mouseUp: (NSEvent *)event;
• (void)mouseDragged: (NSEvent *)event;
• (BOOL)acceptsFirstResponder;

// Internal methods

• (void)setIsSelected: (BOOL)flag;
• (BOOL)isSelected;
• (TigerCollectionView *)collectionView;
• (BOOL)isLeftClickEvent: (NSEvent *)event;
• (void)setDragTargetType: (DragTargetType)type;
• (DragTargetType)dragTargetType;
• (void)updateHighlightState;
• (void)setHighlight: (BOOL)isHighlighted forTextField: (NSTextField *)textField;
• (BOOL)shouldDrawSecondaryHighlight;

@end

static float PointDistance(NSPoint start, NSPoint end) { float deltaX = end.x - start.x; float deltaY = end.y - start.y; return sqrt(deltaX * deltaX + deltaY * deltaY); }

@implementation TigerCollectionView

• (id)initWithFrame: (NSRect)frame { if ((self = [super initWithFrame:frame])) { items = [[NSMutableArray alloc] init]; } return self; }

• (void)dealloc { [[NSNotificationCenter defaultCenter] removeObserver:self]; [items release]; items = nil; [super dealloc]; }

• (void)awakeFromNib { ASSERT(self target] conformsToProtocol: @protocol([[TigerCollectionViewTarget)]);

  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onKeyWindowChanged:) name:NSWindowDidBecomeKeyNotification object:[self window]]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onKeyWindowChanged:) name:NSWindowDidResignKeyNotification object:[self window]];

  [self enclosingScrollView] contentView] setCopiesOnScroll:NO];

  [self registerForDraggedTypes: [[[NSArray arrayWithObjects:NSFilenamesPboardType, DRAG_ITEM_TYPE, nil]];

  [self maximizeViewWidth:nil]; }

• (void)drawRect: (NSRect)rect { /*
  • XXX: This is a hack to work around autohide scrollbars not working
  • correctly. When removing an item causes the vertical scrollbar to
  • be hidden our items don’t automatically resize to fit the new width. *
  • Until that bug is fixed this hack disables the “needsLayout” optimization
  • and forces a layout on every dray. The layout code is pretty fast so this
  • isn’t very expensive. */ needsLayout = YES;

  if (needsLayout) { [self performLayout]; [self maintainNonEmptySelection:0]; } [super drawRect:rect];

  [[NSColor colorWithCalibratedRed:214.0/255.0 green:221.0/255.0 blue:229.0/255.0 alpha:1.0] set]; NSRectFill([self bounds]); }

• (void)addItem: (TigerCollectionViewItem *)item atIndex: (int)index { ASSERT(item); [items insertObject:item atIndex:index]; [item setAutoresizingMask:NSViewWidthSizable | NSViewMinYMargin]; [self addSubview:item]; [self setNeedsLayout:YES]; }

• (void)removeItemAtIndex: (int)index { [self removeItemsAtIndexes: [NSArray arrayWithObject:[NSNumber numberWithInt:index]]]; [self maintainNonEmptySelection:index]; }

• (void)removeAllItems { [items removeAllObjects]; [self setNeedsLayout:YES]; [self setNeedsDisplay:YES]; }

• (int)numberOfItems { return [items count]; }

• (NSArray *)selectedIndexes { NSMutableArray *selectedIndexes = [NSMutableArray array]; int count = [items count]; int i; for (i = 0; i < count; i++) { TigerCollectionViewItem *item = [items objectAtIndex:i]; if ([item isSelected]) { [selectedIndexes addObject:[NSNumber numberWithInt:i]]; } } return selectedIndexes; }

@end // TigerCollectionView

@implementation TigerCollectionView (Private)

• (void)setNeedsLayout: (BOOL)flag { needsLayout = flag; }

• (void)performLayout { // Calculate the total height. float myHeight = 0; NSEnumerator *e = [items objectEnumerator]; TigerCollectionViewItem *item; while ((item = [e nextObject])) { myHeight += [item frame].size.height; }

  // Resize the collection view to fit. NSRect myFrame = [self frame]; [self setFrameSize:NSMakeSize(myFrame.size.width, myHeight)]; if (myFrame.size.height != myHeight) { [self setNeedsDisplay:YES]; }

  // Layout all the items. float yPos = 0; e = [items objectEnumerator]; while ((item = [e nextObject])) { NSRect oldItemFrame = [item frame]; NSRect newItemFrame; newItemFrame.origin.y = yPos; newItemFrame.origin.x = 0; newItemFrame.size.width = myFrame.size.width; newItemFrame.size.height = oldItemFrame.size.height; [item setFrame:newItemFrame];

  yPos += newItemFrame.size.height;
  if (!NSEqualRects(newItemFrame, oldItemFrame)) {
     [item setNeedsDisplay:YES];
  }  }
  

  [self setNeedsLayout:NO]; }

• (BOOL)isFlipped { return YES; }

• (void)startDrag: (NSEvent *)event withItem: (TigerCollectionViewItem *)item { // If the dragged item is selected then drag all selected items too. NSArray *dragIndexes = nil; if ([item isSelected]) { dragIndexes = [self selectedIndexes]; } else { dragIndexes = [NSArray arrayWithObject: [NSNumber numberWithInt:[items indexOfObject:item]]]; }

  // Write data to the paste board. NSPasteboard *pboard = [NSPasteboard pasteboardWithName:NSDragPboard]; [pboard declareTypes:[NSArray arrayWithObjects:DRAG_ITEM_TYPE, NSFilenamesPboardType, nil] owner:self]; [pboard setPropertyList:dragIndexes forType:DRAG_ITEM_TYPE]; [pboard setPropertyList:[self filePathsForIndexes:dragIndexes] forType:NSFilenamesPboardType];

  // Generate the drag image from the dragged items. NSPoint dragPos; NSImage *dragImage = [self dragImageForIndexes:dragIndexes dragPoint:&dragPos];

  // Start the drag. [self dragImage:dragImage at:dragPos offset:NSZeroSize event:event pasteboard:pboard source:self slideBack:YES]; }

• (NSImage *)dragImageForIndexes: (NSArray *)indexes dragPoint: (NSPoint *)dragPoint { // Make an image as big as the visible rect. NSRect dragRect = [self convertRect:[self visibleRect] fromView:[self superview]]; NSImage *dragImage = [[[NSImage alloc] initWithSize:dragRect.size] autorelease];

  NSEnumerator *e = [indexes objectEnumerator]; NSNumber *indexNumber; while ((indexNumber = [e nextObject])) { TigerCollectionViewItem *item = [items objectAtIndex:[indexNumber intValue]];

  NSRect itemRect = [item visibleRect];
  if (NSEqualRects(itemRect, NSZeroRect)) {
     continue;
  }
  
  // Get an image of the dragged view without the selection.
  BOOL oldSelectedValue = [item isSelected];
  [item setIsSelected:NO];
  NSData *itemAsPDF = [item dataWithPDFInsideRect:itemRect];
  [item setIsSelected:oldSelectedValue];
  NSImage *itemImage = [[NSImage alloc] initWithData:itemAsPDF];
  
  // Convert from our flipped axis into the image's non-flipped axis.
  NSPoint pos = [item frame].origin;
  pos.y = dragRect.origin.y + dragRect.size.height - pos.y;
  pos.y -= itemRect.size.height;
  
  // Drag the view's image into the drag image.
  [dragImage lockFocus];
  [itemImage drawAtPoint:pos
                fromRect:NSZeroRect
               operation:NSCompositeSourceOver
                fraction:DRAG_IMAGE_ALPHA];
  [dragImage unlockFocus];
  
  [itemImage release];  }
  

  ASSERT(dragPoint); *dragPoint = NSMakePoint(dragRect.origin.x, dragRect.origin.y + dragRect.size.height);

  return dragImage; }

• (void)itemClicked: (TigerCollectionViewItem *)item event: (NSEvent *)event { NSArray *oldSelection = [self selectedIndexes];

  if (([event modifierFlags] & NSCommandKeyMask) != 0) { [item setIsSelected:![item isSelected]]; } else if (([event modifierFlags] & NSShiftKeyMask) != 0) { [self growSelectionToItem:item]; } else { [self setAllItemsSelected:NO]; [item setIsSelected:YES]; if ([event clickCount] == 2) { self target] performDoubleClickActionForIndex:[items indexOfObject:item; } } [self scrollToItem:item];

  [self testSelectionChanged:oldSelection]; }

• (void)setAllItemsSelected: (BOOL)selected { NSEnumerator *e = [items objectEnumerator]; TigerCollectionViewItem *item; while ((item = [e nextObject])) { [item setIsSelected:selected]; } }

• (void)growSelectionToItem: (TigerCollectionViewItem *)item { NSArray *oldSelection = [self selectedIndexes];

  int itemIndex = [items indexOfObject:item]; int startIndex = oldSelection objectAtIndex:0] intValue]; int endIndex = [[oldSelection lastObject] intValue];

  if (itemIndex < startIndex) { startIndex = itemIndex; } else if (itemIndex > endIndex) { endIndex = itemIndex; }

  int i; for (i = startIndex; i <= endIndex; i++) { [[items objectAtIndex:i] setIsSelected:YES]; }

  [self testSelectionChanged:oldSelection]; }

• (void)moveDown: (id)sender { BOOL shift = ([[[[NSApp currentEvent] modifierFlags] & NSShiftKeyMask) != 0; [self moveSelection:NO byExtending:shift]; }

• (void)moveUp: (id)sender { BOOL shift = ([[NSApp currentEvent] modifierFlags] & NSShiftKeyMask) != 0; [self moveSelection:YES byExtending:shift]; }

• (void)moveSelection: (BOOL)moveUp byExtending: (BOOL)byExtending { if ([items count] == 0) { return; } NSArray *oldSelection = [self selectedIndexes];

  int index = NSNotFound; if (moveUp) { int firstIndex = oldSelection objectAtIndex:0] intValue]; firstIndex–; if (firstIndex >= 0) { index = firstIndex; } } else { int lastIndex = [[oldSelection lastObject] intValue]; lastIndex++; if (lastIndex < [items count]) { index = lastIndex; } }

  if (index != [[NSNotFound) { if (!byExtending) { [self setAllItemsSelected:NO]; } TigerCollectionViewItem *item = [items objectAtIndex:index]; [item setIsSelected:YES]; [self scrollToItem:item]; }

  [self testSelectionChanged:oldSelection]; }

• (void)scrollToItem: (TigerCollectionViewItem *)item { NSRect itemFrame = [item frame]; NSPoint top, bottom; bottom.y = NSMaxY(itemFrame); top.y = NSMinY(itemFrame); top.x = 0; bottom.x = 0;

  NSRect visibleRect = [self visibleRect]; BOOL bottomVisible = NSPointInRect(bottom, visibleRect); BOOL topVisible = NSPointInRect(top, visibleRect); if (!topVisible || !bottomVisible) { NSPoint scrollPos; if (!bottomVisible) { scrollPos.y = bottom.y - visibleRect.size.height; } else { scrollPos.y = top.y; } scrollPos.x = 0;

  NSClipView *clipView = self enclosingScrollView] contentView];
  [clipView scrollToPoint:[clipView constrainScrollPoint:scrollPos;
  self enclosingScrollView] reflectScrolledClipView:clipView];  } }
  

• (void)selectAll: (id)sender { [[NSArray *oldSelection = [self selectedIndexes]; [self setAllItemsSelected:YES]; [self testSelectionChanged:oldSelection]; }

• (void)maintainNonEmptySelection: (int)index { NSArray *oldSelection = [self selectedIndexes]; if ([items count] > 0 && [oldSelection count] == 0) { int selectionIndex = index; if (selectionIndex < 0) { selectionIndex = 0; } else if (selectionIndex >= [items count]) { selectionIndex = [items count] - 1; } items objectAtIndex:selectionIndex] setIsSelected:YES];

  [self testSelectionChanged:oldSelection];  } }
  

• (void)keyDown: ([[NSEvent *)event { unichar u = event charactersIgnoringModifiers] characterAtIndex: 0];

  if (u == [[NSDeleteCharacter || u == NSDeleteFunctionKey) { // Forward or backward delete. [self interpretKeyEvents:[NSArray arrayWithObject:event]]; } else if (u == NSEnterCharacter || u == NSCarriageReturnCharacter) { NSArray *indexes = [self selectedIndexes]; if ([indexes count] > 0) { self target] performDoubleClickActionForIndex: [[indexes objectAtIndex:0] intValue; } } else { [super keyDown:event]; } }

• (void)deleteBackward: (id)sender { NSArray *indexes = [self selectedIndexes]; if ([indexes count] > 0 && self target] shouldRemoveItemsAtIndexes:indexes]) { [self removeItemsAtIndexes:indexes]; [self maintainNonEmptySelection:[[indexes objectAtIndex:0] intValue] - 1]; [[self window] makeFirstResponder:self]; } }

• (void)deleteForward: (id)sender { [[NSArray *indexes = [self selectedIndexes]; if ([indexes count] > 0 && self target] shouldRemoveItemsAtIndexes:indexes]) { [self removeItemsAtIndexes:indexes]; [self maintainNonEmptySelection:[[indexes objectAtIndex:0] intValue; self window] makeFirstResponder:self]; } }

• (void)removeItemsAtIndexes: ([[NSArray *)indexes { if ([indexes count] == 0) { return; }

  NSMutableIndexSet *indexSet = [NSMutableIndexSet indexSet];

  NSEnumerator *e = [indexes objectEnumerator]; NSNumber *indexNumber; while ((indexNumber = [e nextObject])) { int index = [indexNumber intValue]; TigerCollectionViewItem *item = [items objectAtIndex:index]; [item removeFromSuperview]; [indexSet addIndex:index]; }

  [items removeObjectsAtIndexes:indexSet];

  /*

  • Need to force the layout to change right away so that scrolling and
  • selection code will work. */ [self performLayout]; }

• (NSDragOperation)draggingEntered: (id)sender { return [self draggingUpdated:sender]; }

• (void)draggingExited: (id)sender { [self setDragTarget:nil draggingInfo:sender]; }

• (BOOL)prepareForDragOperation: (id)sender { BOOL acceptDrop = NO; NSArray *dragTypes = sender draggingPasteboard] types];

  if ([dragTypes containsObject:DRAG_ITEM_TYPE]) { acceptDrop = YES; } else if ([dragTypes containsObject:[[NSFilenamesPboardType]) { NSArray *filePaths = sender draggingPasteboard] propertyListForType:[[NSFilenamesPboardType]; acceptDrop = self target] dragOperationForFiles:filePaths] != [[NSDragOperationNone; }

  if (!acceptDrop) { [self setDragTarget:nil draggingInfo:sender]; } return acceptDrop; }

• (BOOL)performDragOperation: (id)sender { int destIndex = [self dragTargetIndex]; ASSERT(destIndex != NSNotFound); [self setDragTarget:nil draggingInfo:sender];

  NSArray *dragTypes = sender draggingPasteboard] types]; if ([dragTypes containsObject:DRAG_ITEM_TYPE]) { [[NSArray *indexes = sender draggingPasteboard] propertyListForType:DRAG_ITEM_TYPE]; [[self target] dragItemsAtIndexes:indexes toIndex:destIndex];
  } else if ([dragTypes containsObject:[[NSFilenamesPboardType]) { NSArray *filePaths = sender draggingPasteboard] propertyListForType:[[NSFilenamesPboardType]; self target] dragFiles:filePaths toIndex:destIndex]; } return YES; }

• ([[NSDragOperation)draggingUpdated: (id)sender { NSPoint dragPos = self superview] convertPoint:[sender draggingLocation] fromView:nil]; [[NSView *targetView = [self hitTest:dragPos];

  NSDragOperation dragOperation = NSDragOperationNone; NSArray *dragTypes = sender draggingPasteboard] types]; if ([dragTypes containsObject:DRAG_ITEM_TYPE]) { dragOperation = [[NSDragOperationMove; } else if ([dragTypes containsObject:NSFilenamesPboardType]) { NSArray *filePaths = sender draggingPasteboard] propertyListForType:[[NSFilenamesPboardType]; dragOperation = self target] dragOperationForFiles:filePaths]; }

  if (dragOperation == [[NSDragOperationNone) { [self setDragTarget:nil draggingInfo:sender]; } else { [self setDragTarget:targetView draggingInfo:sender]; } return dragOperation; }

• (BOOL)wantsPeriodicDraggingUpdates { return NO; }

• (NSDragOperation)draggingSourceOperationMaskForLocal: (BOOL)isLocal { if (isLocal) { return NSDragOperationMove; } else { return NSDragOperationLink; } }

• (int)indexFromDragTarget: (NSView *)targetView draggingInfo: (id)draggingInfo { int index = NSNotFound; if (targetView && [targetView isKindOfClass:[TigerCollectionViewItem class]]) { index = [items indexOfObject:targetView]; }

  if (index != NSNotFound) { TigerCollectionViewItem *item = [items objectAtIndex:index]; NSPoint viewPos = [item convertPoint:[draggingInfo draggingLocation] fromView:nil]; NSRect bounds = [item bounds]; if (viewPos.y < bounds.size.height / 2.0) { index = fmin(index + 1, [items count]); } }

  return index; }

• (void)setDragTarget: (NSView *)targetView draggingInfo: (id)draggingInfo { int newDragTargetIndex = [self indexFromDragTarget:targetView draggingInfo:draggingInfo]; int curDragTargetIndex = [self dragTargetIndex]; if (newDragTargetIndex != curDragTargetIndex) { [self setIndex:curDragTargetIndex isDragTarget:NO]; [self setIndex:newDragTargetIndex isDragTarget:YES]; } }

• (void)setIndex: (int)index isDragTarget: (BOOL)isDragTarget { if (index != NSNotFound) { DragTargetType dragTargetType = isDragTarget ? DragTargetType_Top : DragTargetType_None; int actualIndex = index; if (actualIndex == [items count]) { actualIndex = [items count] - 1; if (isDragTarget) { dragTargetType = DragTargetType_Bottom; } } items objectAtIndex:actualIndex] setDragTargetType:dragTargetType]; } }

• (id<[[TigerCollectionViewTarget>)target { return target; }

• (int)dragTargetIndex { int count = [items count]; int i; for (i = 0; i < count; i++) { TigerCollectionViewItem *item = [items objectAtIndex:i]; if ([item dragTargetType] == DragTargetType_Top) { return i; } else if ([item dragTargetType] == DragTargetType_Bottom) { return i + 1; } } return NSNotFound; }

• (void)resizeWithOldSuperviewSize: (NSSize)oldBoundsSize { [super resizeWithOldSuperviewSize:oldBoundsSize]; [self performSelector:@selector(maximizeViewWidth:) withObject:nil afterDelay:0.10]; //[self maximizeViewWidth:nil]; }

• (void)maximizeViewWidth: (id)sender { float width = [self enclosingScrollView] contentView] frame].size.width; [[NSRect myOldFrame = [self frame]; if (myOldFrame.size.width != width) { [self setFrameSize:NSMakeSize(width, myOldFrame.size.height)]; [self setNeedsDisplay:YES]; } }

• (void)onKeyWindowChanged: (NSNotification *)notification { [self setNeedsDisplay:YES];

  NSEnumerator *e = [items objectEnumerator]; TigerCollectionViewItem *item; while ((item = [e nextObject])) { [item updateHighlightState]; } }

• (void)testSelectionChanged: (NSArray *)oldSelection { BOOL didChange = NO; if (!oldSelection) { didChange = YES; } else { NSArray *newSelection = [self selectedIndexes]; didChange = ![oldSelection isEqualToArray:newSelection]; }

  if (didChange) { self target] onSelectionDidChange]; } }

• ([[NSArray *)filePathsForIndexes: (NSArray *)indexes { NSMutableArray *filePaths = [NSMutableArray array];

  NSEnumerator *e = [indexes objectEnumerator]; NSNumber *indexNumber; while ((indexNumber = [e nextObject])) { NSString *filePath = self target] filePathForIndex:[indexNumber intValue; if (filePath) { [filePaths addObject:filePath]; } } return filePaths; }

@end // TigerCollectionView (Private)

@implementation TigerCollectionViewItem

• (void)dealloc { [cachedTextColors release]; cachedTextColors = nil; [super dealloc]; }

• (void)awakeFromNib { [self setNextResponder:[self superview]]; }

• (void)drawRect: (NSRect)rect { [super drawRect:rect];

  if ([self isSelected]) { if ([self shouldDrawSecondaryHighlight]) { [[NSColor grayColor] set]; } else { [[NSColor blueColor] set]; } NSRectFill(rect); }

  if (dragTargetType != DragTargetType_None) { NSRect dRect = [self bounds]; if (dragTargetType == DragTargetType_Top) { dRect.origin.y = dRect.size.height - 2.0; } dRect.size.height = 2; [[NSColor blackColor] set]; NSRectFill(dRect); } }

@end // TigerCollectionViewItem

@implementation TigerCollectionViewItem (Private)

• (NSMenu *)menuForEvent:(NSEvent *)event { if (![self isSelected]) { self collectionView] itemClicked:self event:event]; } return [[self superview] menuForEvent:event]; }

• ([[NSView *)hitTest: (NSPoint)point { NSView *result = [super hitTest:point]; if (result && ![result isKindOfClass:[NSButton class]]) { return self; } else { return result; } }

• (void)mouseDown: (NSEvent *)event { if ([self isLeftClickEvent:event]) { mouseDownPos = [event locationInWindow]; } }

• (void)mouseUp: (NSEvent *)event { if ([self isLeftClickEvent:event]) { self collectionView] itemClicked:self event:event]; } }

• (void)mouseDragged: ([[NSEvent *)event { if ([self isLeftClickEvent:event]) { NSPoint mouseDragPos = [event locationInWindow]; float distance = PointDistance(mouseDragPos, mouseDownPos); if (distance > DRAG_START_DISTANCE) { self collectionView] startDrag:event withItem:self]; } } }

• (BOOL)acceptsFirstResponder { return NO; }

• (void)setIsSelected: (BOOL)flag { if (isSelected != flag) { isSelected = flag; [self updateHighlightState]; [self setNeedsDisplay:YES]; } }

• (BOOL)isSelected { return isSelected; }

• ([[TigerCollectionView *)collectionView { ASSERT(self superview] isKindOfClass:[[[TigerCollectionView class]]); return (TigerCollectionView *)[self superview]; }

• (BOOL)isLeftClickEvent: (NSEvent *)event { return [event buttonNumber] == 0 && ([event modifierFlags] & NSControlKeyMask) == 0; }

• (void)setDragTargetType: (DragTargetType)type { if (dragTargetType != type) { dragTargetType = type; [self setNeedsDisplay:YES]; } }

• (DragTargetType)dragTargetType { return dragTargetType; }

• (void)updateHighlightState { BOOL isHighlighted = [self isSelected] && ![self shouldDrawSecondaryHighlight];

  NSEnumerator *e = self subviews] objectEnumerator]; id subview; while ((subview = [e nextObject])) { if ([subview isKindOfClass:[[[NSTextField class]]) { [self setHighlight:isHighlighted forTextField:(NSTextField *)subview];
  } else if ([subview respondsToSelector:@selector(setIsSelected:)]) { [subview setIsSelected:isHighlighted]; } } }

• (void)setHighlight: (BOOL)isHighlighted forTextField: (NSTextField *)textField { NSNumber *key = [NSNumber numberWithInt:[textField hash]];

  if (!cachedTextColors) { cachedTextColors = [[NSMutableDictionary alloc] init]; }

  if (isHighlighted) { if (![cachedTextColors objectForKey:key]) { [cachedTextColors setObject:[textField textColor] forKey:key]; [textField setTextColor:[NSColor whiteColor]]; } } else { if ([cachedTextColors objectForKey:key]) { [textField setTextColor:[cachedTextColors objectForKey:key]]; [cachedTextColors removeObjectForKey:key]; } } }

• (BOOL)shouldDrawSecondaryHighlight { if (self window] isKeyWindow]) { return NO; } else { return YES; } }

@end // [[TigerCollectionViewItem (Private)