- (BOOL)collectionView:(UICollectionView *)collectionView canMoveItemAtIndexPath:(NSIndexPath *)indexPath;

- (void)collectionView:(UICollectionView *)collectionView moveItemAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath*)destinationIndexPath;

// 设置手势

- (void)setupGesture

{

    UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handlelongGesture:)];

    [self.collectionView addGestureRecognizer:longPress];

}

- (void)handlelongGesture:(UILongPressGestureRecognizer *)longGesture {

    //判断手势状态

    switch (longGesture.state) {

        case UIGestureRecognizerStateBegan:
　　　　{

            //判断手势落点位置是否在路径上

            NSIndexPath *indexPath = [self.collectionView indexPathForItemAtPoint:[longGesture locationInView:self.collectionView]];

            if (indexPath == nil) {

                break;

            }

            //在路径上则开始移动该路径上的cell

            [self.collectionView beginInteractiveMovementForItemAtIndexPath:indexPath];

        }

            break;

        case UIGestureRecognizerStateChanged:

            //移动过程当中随时更新cell位置

            [self.collectionView updateInteractiveMovementTargetPosition:[longGesture locationInView:self.collectionView]];

            break;

        case UIGestureRecognizerStateEnded:

            //移动结束后关闭cell移动

            [self.collectionView endInteractiveMovement];

            break;

        default:

            [self.collectionView cancelInteractiveMovement];

            break;

    }

}

- (BOOL)collectionView:(UICollectionView *)collectionView canMoveItemAtIndexPath:(NSIndexPath *)indexPath{

    //返回YES允许其item移动

    return YES;

}

- (void)collectionView:(UICollectionView *)collectionView moveItemAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath*)destinationIndexPath {

    //取出源item数据

    id objc = [_dataSource objectAtIndex:sourceIndexPath.item];

    //从资源数组中移除该数据

    [_dataSource removeObject:objc];

    //将数据插入到资源数组中的目标位置上

    [_dataSource insertObject:objc atIndex:destinationIndexPath.item];

}