gistfile1.diff

diff --git a/AppKit/CPCollectionView.j b/AppKit/CPCollectionView.j
index c05deee..cabb056 100644
--- a/AppKit/CPCollectionView.j
+++ b/AppKit/CPCollectionView.j
@@ -110,6 +110,7 @@
         _verticalMargin = 5.0;
         _tileWidth = -1.0;
         
+        _isSelectable = YES;
         _selectionIndexes = [CPIndexSet indexSet];
     }
     
@@ -497,21 +498,24 @@
     return _maxItemSize;
 }
 
-- (void)mouseUp:(CPEvent)anEvent
-{
-    if ([_selectionIndexes count] && [anEvent clickCount] == 2 && [_delegate respondsToSelector:@selector(collectionView:didDoubleClickOnItemAtIndex:)])
-        [_delegate collectionView:self didDoubleClickOnItemAtIndex:[_selectionIndexes firstIndex]];
-}
-
 - (void)mouseDown:(CPEvent)anEvent
 {
+    [super mouseDown:anEvent];
+    
     var location = [self convertPoint:[anEvent locationInWindow] fromView:nil],
         row = FLOOR(location.y / (_itemSize.height + _verticalMargin)),
         column = FLOOR(location.x / (_itemSize.width + _horizontalMargin)),
         index = row * _numberOfColumns + column;
         
     if (index >= 0 && index < _items.length)
+    {
         [self setSelectionIndexes:[CPIndexSet indexSetWithIndex:index]];
+        
+        if ([anEvent clickCount] == 2 && [_delegate respondsToSelector:@selector(collectionView:didDoubleClickOnItemAtIndex:)])
+            [_delegate collectionView:self didDoubleClickOnItemAtIndex:[_selectionIndexes firstIndex]];
+    }
+    else
+        [self setSelectionIndexes:[CPIndexSet indexSet]];
 }
 
 - (void)mouseDragged:(CPEvent)anEvent