How can I change the scroll direction in UICollect

问题:

I have a UICollectionView in my storyboard based iOS app. When the device is in the portrait orientation I'd like it to scroll vertically, and when it's in Landscaper I'd like it to scroll horizontally.

In UICollectionView I can see the scrollEnabled member, but I can see no way to set the scroll direction. Have I missed something?

回答1:

UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
[flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];

---

Note too that it seems to be fine to call this in prepareForLayout in your flow layout...

@interface LayoutHorizontalThings : UICollectionViewFlowLayout
@end

@implementation LayoutHorizontalBooks
-(void)prepareLayout
    {
    [super prepareLayout];

    self.scrollDirection = UICollectionViewScrollDirectionHorizontal;

    self.minimumInteritemSpacing = 0;
    self.minimumLineSpacing = 0;
    self.itemSize = CGSizeMake(110,130);
    self.sectionInset = UIEdgeInsetsMake(0, 0, 0, 0);
    }

回答2:

Set the scrollDirection of the collection view's collectionViewLayout.

Docs are here.

回答3:

You should try this:

- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration{

  UICollectionViewFlowLayout *layout = (UICollectionViewFlowLayout *)[self.collectionView collectionViewLayout];

  if ((toInterfaceOrientation == UIInterfaceOrientationLandscapeRight) || (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft)){
    layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
  }
  else{
    layout.scrollDirection = UICollectionViewScrollDirectionVertical;
  } 
}

In Swift:

override func willRotateToInterfaceOrientation(toInterfaceOrientation: UIInterfaceOrientation, duration: NSTimeInterval) {

    var layout = self.collectionView.collectionViewLayout as! UICollectionViewFlowLayout

    if ((toInterfaceOrientation == UIInterfaceOrientation.LandscapeLeft) || (toInterfaceOrientation == UIInterfaceOrientation.LandscapeRight)){

        layout.scrollDirection = UICollectionViewScrollDirection.Vertical
    }
    else{
       layout.scrollDirection = UICollectionViewScrollDirection.Horizontal
    }

}

回答4:

Swift 4 and 4.2

if let layout = collectionViewObj.collectionViewLayout as? UICollectionViewFlowLayout {
        layout.scrollDirection = .vertical  // .horizontal
    }

回答5:

Kudos to Mundi and Dan Rosenstark for their answer, here's the swift 4.2 version.

if let flowLayout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout {
    flowLayout.scrollDirection = .horizontal
}

回答6:

Do that in your storyboard. From identity inspector and select direction and give your direction.