paging in UIScrollView is a great feature, what I need here is to set the paging to a smaller distance, for example I want my UIScrollView to page less size that the UIScrollView frame width. Thanks
There is a UIScrollView
delegate method you can use. Set your class as the scroll view's delegate, and then implement the following:
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset
{
CGFloat kMaxIndex = 23;
CGFloat targetX = scrollView.contentOffset.x + velocity.x * 60.0;
CGFloat targetIndex = 0.0;
if (velocity.x > 0) {
targetIndex = ceil(targetX / (kCellWidth + kCellSpacing));
} else if (velocity.x == 0) {
targetIndex = round(targetX / (kCellWidth + kCellSpacing));
} else if (velocity.x < 0) {
targetIndex = floor(targetX / (kCellWidth + kCellSpacing));
}
if (targetIndex < 0)
targetIndex = 0;
if (targetIndex > kMaxIndex)
targetIndex = kMaxIndex;
targetContentOffset->x = targetIndex * (kCellWidth + kCellSpacing);
//scrollView.decelerationRate = UIScrollViewDecelerationRateFast;//uncomment this for faster paging
}
The velocity parameter is necessary to make sure the scrolling feels natural and doesn't end abruptly when a touch ends with your finger still moving. The cell width and cell spacing are the page width and spacing between pages in your view. In this case, I'm using a UICollectionView
.