UICollectionView水平滚动(UICollectionView Scrolling Horizontally)

 我在我的iOS应用程序中实现了一个UICollectionView。 我有它所以每个单元格是屏幕的宽度，我想拥有它，所以当水平滚动它锁定到可见单元格并将其移动到屏幕的中心。 下面的代码我只适用于第一个单元格。 我不明白如何让这个用于任何用户可见的单元格。 
 
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
    int index  = 0;
    for (TextCell * t in [_tabBarCollectionView visibleCells]) {
        if ((t.center.x>0)&&(t.center.x<[[UIScreen mainScreen]bounds].size.width)) {
            [_tabBarCollectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForRow:index inSection:0] atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally animated:YES];
            break;
        }
        index++;
    }

}

I am implementing a UICollectionView in my iOS app. I have it so each cell is the width of the screen and I want to have it so when scrolling horizontally it locks onto the visible cell and moves it to the center of the screen. The code bellow I have only works for the first cell. I don't understand how to get this to work for any cell the user has visible.
 
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
    int index  = 0;
    for (TextCell * t in [_tabBarCollectionView visibleCells]) {
        if ((t.center.x>0)&&(t.center.x<[[UIScreen mainScreen]bounds].size.width)) {
            [_tabBarCollectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForRow:index inSection:0] atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally animated:YES];
            break;
        }
        index++;
    }

}

原文：https://stackoverflow.com/questions/16256262