Fixes #38

DraggableCollectionView/Helpers/LSCollectionViewHelper.m

@@ -11,6 +11,7 @@
 #import <QuartzCore/QuartzCore.h>
 
 static int kObservingCollectionViewLayoutContext;
+static NSString* const kObservingCollectionViewLayoutKeyPath = @"collectionViewLayout";
 
 #ifndef CGGEOMETRY__SUPPORT_H_
 CG_INLINE CGPoint
@@ -49,7 +50,7 @@ - (id)initWithCollectionView:(UICollectionView *)collectionView
     if (self) {
         _collectionView = collectionView;
         [_collectionView addObserver:self
-                          forKeyPath:@"collectionViewLayout"
+                          forKeyPath:kObservingCollectionViewLayoutKeyPath
                              options:0
                              context:&kObservingCollectionViewLayoutContext];
         _scrollingEdgeInsets = UIEdgeInsetsMake(50.0f, 50.0f, 50.0f, 50.0f);
@@ -58,7 +59,6 @@ - (id)initWithCollectionView:(UICollectionView *)collectionView
         _longPressGestureRecognizer = [[UILongPressGestureRecognizer alloc]
                                        initWithTarget:self
                                        action:@selector(handleLongPressGesture:)];
-        [_collectionView addGestureRecognizer:_longPressGestureRecognizer];
 
         _panPressGestureRecognizer = [[UIPanGestureRecognizer alloc]
                                       initWithTarget:self action:@selector(handlePanGesture:)];
@@ -73,11 +73,20 @@ - (id)initWithCollectionView:(UICollectionView *)collectionView
             }
         }
 
+        [_collectionView addGestureRecognizer:_longPressGestureRecognizer];
+
         [self layoutChanged];
     }
     return self;
 }
 
+- (void)dealloc
+{
+    [_collectionView removeObserver:self
+                         forKeyPath:kObservingCollectionViewLayoutKeyPath
+                            context:&kObservingCollectionViewLayoutContext];
+}
+
 - (LSCollectionViewLayoutHelper *)layoutHelper
 {
     return [(id <UICollectionViewLayout_Warpable>)self.collectionView.collectionViewLayout layoutHelper];

DraggableCollectionView/UICollectionView+Draggable.h

@@ -12,4 +12,8 @@
 @property (nonatomic, assign) BOOL draggable;
 @property (nonatomic, assign) UIEdgeInsets scrollingEdgeInsets;
 @property (nonatomic, assign) CGFloat scrollingSpeed;
+
+// Call this method from the -dealloc method of any class that accesses the properties above
+- (void)removeHelper;
+
 @end

DraggableCollectionView/UICollectionView+Draggable.m

@@ -20,6 +20,14 @@ - (LSCollectionViewHelper *)getHelper
     return helper;
 }
 
+- (void)removeHelper
+{
+    LSCollectionViewHelper *helper = objc_getAssociatedObject(self, "LSCollectionViewHelper");
+    if (helper) {
+        objc_setAssociatedObject(self, "LSCollectionViewHelper", nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+    }
+}
+
 - (BOOL)draggable
 {
     return [self getHelper].enabled;