2019-08-29 透明cell

透明cell

-(instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier {
    if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {
        //加上 dispatch_after 能够获取到 设置 行高 后 cell 的高度，不加 cell 还是 原来的 bounds
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [self initUI];
        });
    }
    return self;
}
- (void)initUI {
    UIScrollView *scrollView = [[UIScrollView alloc]initWithFrame:self.bounds];
    scrollView.contentSize = CGSizeMake(self.bounds.size.width, self.bounds.size.height);
    scrollView.alwaysBounceVertical = YES;
    [self.contentView addSubview:scrollView];
    self.scrollView.userInteractionEnabled = NO;
    self.scrollView = scrollView;

    UIImageView *imageView = [[UIImageView alloc] init];
    imageView.image = [UIImage imageNamed:@"timg.jpg"];
    CGFloat height = imageView.image.size.height;
    imageView.frame = CGRectMake(0, - height, kWidth, height);//根据图片尺寸设计坐标
    [scrollView addSubview:imageView];
}
- (void)setContendOffset:(CGFloat)contendOffset{
    _offset = contendOffset;
    [self.scrollView setContentOffset:CGPointMake(0, -_offset) animated:NO];//注意不要动画！！！
}

ViewController

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    static NSString *CELLREUSE = @"cell_reuse";
    //第6个位透明cell
    if (indexPath.row == 5) {
        ShowCell *cell = [[SHowCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"showcell"];
        return cell;
    }else {
        MyTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CELLREUSE];
        if (!cell) {
            cell = [[MyTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CELLREUSE];
        }
        return cell;
    }
}
//实现scrollView滚动代理方法
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
    CGFloat contentPointY = 5 * cellHeight - kHeight;
    CGFloat contentOffSet = scrollView.contentOffset.y;
    if (contentOffSet >= contentPointY && contentOffSet <= 5 * cellHeight) {
        NSIndexPath *indexs = [NSIndexPath indexPathForRow:5 inSection:0];
        SowCell *showcell = [self.tableView cellForRowAtIndexPath:indexs];
        showcell.contendOffset = contentOffSet - contentPointY;
    }
}