iOS UICollectionView高级用法(长按自由移动cell)

iOS 9之后: 示例如下

效果

前言: 看完你可以学到哪些呢? 就是文章标题那么多, 只有那么多. . 手残效果图没弄好.

@property (nonatomic, strong) UICollectionView *xtCollectionView;
@property (nonatomic, strong) UICollectionViewFlowLayout *flowLayout;
@property (nonatomic, strong) CALayer *dotLayer;
@property (nonatomic, assign) CGFloat endPoint_x;
@property (nonatomic, assign) CGFloat endPoint_y;
@property (nonatomic, strong) UIBezierPath *path;
@property (nonatomic, strong) NSMutableArray *array;
@property (nonatomic, strong) UILongPressGestureRecognizer *longPress;

初始化一个数组

self.array = [NSMutableArray arrayWithObjects:@"红包", @"转账", @"手机充值", @"芝麻信用",
                  @"天猫", @"生活缴费", @"蚂蚁呗", @"世界那么大",
                  @"余额宝", @"安全快付", @"蚂蚁聚宝", @"哈哈",@"红包1", @"转账1", @"手机充值1", @"芝麻信用1",
                  @"天猫1", @"生活缴费1", @"蚂蚁呗1", @"世界那么大1",
                  @"余额宝1", @"安全快付1", @"蚂蚁聚宝1", @"哈哈1",  nil];

创建CollectionView

- (UICollectionView *)xtCollectionView
{
    if (!_xtCollectionView) {
        _flowLayout = [[UICollectionViewFlowLayout alloc] init];
        _flowLayout.minimumLineSpacing = 1;
        _flowLayout.minimumInteritemSpacing = 1;
        _xtCollectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 20, Screen_Width, Screen_Height - 20) collectionViewLayout:_flowLayout];
        _xtCollectionView.dataSource = self;
        _xtCollectionView.backgroundColor = [UIColor colorWithRed:0.8568 green:0.8568 blue:0.8568 alpha:1.0];
        _xtCollectionView.delegate = self;
        [_xtCollectionView registerClass:[XTCollectCell class] forCellWithReuseIdentifier:@"cellIdentiifer"];
    }
    return _xtCollectionView;
}

添加一个长按的手势

_longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(lonePressMoving:)];
[self.xtCollectionView addGestureRecognizer:_longPress];

手势方法的实现

- (void)lonePressMoving:(UILongPressGestureRecognizer *)longPress
{

    switch (_longPress.state) {
        case UIGestureRecognizerStateBegan: {
            {
                NSIndexPath *selectIndexPath = [self.xtCollectionView indexPathForItemAtPoint:[_longPress locationInView:self.xtCollectionView]];
                // 找到当前的cell
                XTCollectCell *cell = (XTCollectCell *)[self.xtCollectionView cellForItemAtIndexPath:selectIndexPath];
                // 定义cell的时候btn是隐藏的, 在这里设置为NO
                [cell.btnDelete setHidden:NO];
                [_xtCollectionView beginInteractiveMovementForItemAtIndexPath:selectIndexPath];
            }
            break;
        }
        case UIGestureRecognizerStateChanged: {
                [self.xtCollectionView updateInteractiveMovementTargetPosition:[longPress locationInView:_longPress.view]];
            break;
        }
        case UIGestureRecognizerStateEnded: {
                [self.xtCollectionView endInteractiveMovement];
            break;
        }
        default: [self.xtCollectionView cancelInteractiveMovement];
            break;
    }
}

移动方法

- (void)collectionView:(UICollectionView *)collectionView moveItemAtIndexPath:(nonnull NSIndexPath *)sourceIndexPath toIndexPath:(nonnull NSIndexPath *)destinationIndexPath
{
    NSIndexPath *selectIndexPath = [self.xtCollectionView indexPathForItemAtPoint:[_longPress locationInView:self.xtCollectionView]];
    // 找到当前的cell
    XTCollectCell *cell = (XTCollectCell *)[self.xtCollectionView cellForItemAtIndexPath:selectIndexPath];
    [cell.btnDelete setHidden:YES];
    [self.array exchangeObjectAtIndex:sourceIndexPath.item withObjectAtIndex:destinationIndexPath.item];
    [self.xtCollectionView reloadData];
}

效果图的解释: collectionView的可编辑状态是"假的", 只是对数据进行了处理
你可能想知道动画的实现可以看我的另一篇博客iOS仿美团外卖饿了吗App点餐动画

iOS9之前可以参照这个

效果

Github上很早的项目了, 希望对有需要的同学有启发的作用, 点我下载感谢作者

补充说明: LXReorderableCollectionViewFlowLayout 这个继承于UICollectionViewFlowLayout So 对于cell的调整是比较随意像系统的一样.
比如调整cell的间距你可以这样.

调整---cell间距

LXReorderableCollectionViewFlowLayout *flowLayout = [[LXReorderableCollectionViewFlowLayout alloc] init];
    flowLayout.minimumLineSpacing = ...;
    flowLayout.minimumInteritemSpacing = ...;
    _collection = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 0, s_w, s_h) collectionViewLayout:flowLayout];

搭配下面这个方法

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
    return CGSizeMake(..., ...);
}