I tried to add UISwipeGestureRecognizer to my programmatically created UIColletionView, but the recognizer never call the action. Here is my code.

```
UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
flowLayout.scrollDirection = UICollectionViewScrollDirectionVertical;
self.currentCollectionView = [[UICollectionView alloc] initWithFrame:CGRectMake( 0.0f, 54.0f, 320.0f, 470.0f) collectionViewLayout:flowLayout];
[self.currentCollectionView setBackgroundColor:[UIColor whiteColor]];
self.currentCollectionView.delegate = self;
self.currentCollectionView.dataSource = self;
self.currentCollectionView.showsHorizontalScrollIndicator = NO;
self.currentCollectionView.showsVerticalScrollIndicator = NO;
self.currentCollectionView.scrollEnabled = YES;
self.currentCollectionView.bounces = YES;
[self.currentCollectionView setBackgroundColor:[UIColor lightGrayColor]];
[self.currentCollectionView registerClass:[TripexpPhotoCell class] forCellWithReuseIdentifier:@"photoCell"];
[self.view addSubview:self.currentCollectionView];
self.swipeUpRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeUp:)];
self.swipeUpRecognizer.numberOfTouchesRequired = 1;
[self.swipeUpRecognizer setDirection:UISwipeGestureRecognizerDirectionUp];

self.swipeDownRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(didSwipeDown:)];
self.swipeDownRecognizer.numberOfTouchesRequired = 1;
[self.swipeDownRecognizer setDirection:UISwipeGestureRecognizerDirectionDown];

[self.currentCollectionView addGestureRecognizer:self.swipeDownRecognizer];
[self.currentCollectionView addGestureRecognizer:self.swipeUpRecognizer];

```

And here is the function and the delegate for simultaneously receiving the same recognizer

```
#pragma mark - UISwipeGestureRecognizer Action
-(void)didSwipeUp: (UISwipeGestureRecognizer*) recognizer {
    NSLog(@"Swiped Up");
}

-(void)didSwipeDown: (UISwipeGestureRecognizer*) recognizer {
    NSLog(@"Swiped Down");
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer     shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    NSLog(@"Asking permission");
    return YES;
}

```

I also looped inside the UICollectionView and check if there is any existing UISwipeGestureRecognizer but I found none. So after I attached my 2 recognizers, then I see those 2.