IOS UICollectionView 横向分页加载(左滑加载数据)

@interface ONMessageHeaderView ()

@property (strong, nonatomic)UICollectionView collectionView;
@property (nonatomic , assign) NSInteger visitorPage;
/*

• 旋转图标
  */
  @property (nonatomic, weak) UIActivityIndicatorView *indicatorView;
  @end

@implementation ONMessageHeaderView

• (instancetype)initWithFrame:(CGRect)frame{

  if (self = [super initWithFrame:frame]) {

    [self setUpChildView];
    // 获取访客细心记录
    _visitorPage = 1;
    //        [self InitVisitData];
  

  }
  return self;
  }

• (void)setUpChildView{

  CGFloat startX = 10;

  CGFloat startY = 5;

  CGFloat cgStartY = 13;

  //背景
  UIView * bgV = [[UIView alloc] initWithFrame:CGRectMake(0, cgStartY, SCREEN_WIDTH, self.height - cgStartY * 2)];

  bgV.backgroundColor = [UIColor whiteColor];

  [self addSubview:bgV];

  UIImageView * seeImage = [[UIImageView alloc] initWithFrame:CGRectMake(startX,startY + 5, 25, 20)];

  seeImage.image = [UIImage imageNamed:@"message_Visitor"];

  [bgV addSubview:seeImage];

  //标题
  UILabel * titleL = [[UILabel alloc] initWithFrame:CGRectMake(CGRectGetMaxY(seeImage.frame) +10, startY, SCREEN_WIDTH, 30)];

  titleL.text = @"我的访客";

  titleL.font = ONFont(16);

  [bgV addSubview:titleL];

  //布局
  UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];

  layout.itemSize = CGSizeMake(ONCellWidth, ONCellHight);

  [layout setScrollDirection:UICollectionViewScrollDirectionHorizontal];

  layout.sectionInset = UIEdgeInsetsMake(0,10, 0, 10);

  layout.minimumInteritemSpacing = 10;

  layout.minimumLineSpacing = 10;

  //访客
  UICollectionView * visiterV = [[UICollectionView alloc] initWithFrame:CGRectMake(0, CGRectGetMaxY(titleL.frame) +5, SCREEN_WIDTH, ONCellHight) collectionViewLayout:layout];

  visiterV.showsHorizontalScrollIndicator = NO;

  visiterV.backgroundColor = [UIColor whiteColor];

  self.collectionView = visiterV;

  [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"UICollectionViewCell"];

  visiterV.collectionViewLayout = layout;

  visiterV.delegate = self;

  visiterV.dataSource = self;

  [bgV addSubview:visiterV];

}

• (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
  return _visitorRecordArray.count;
  }

• (UICollectionViewCell * )collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{

  static NSString * CellIdentifier = @"UICollectionViewCell";
  VisitorRecordModel *user = _visitorRecordArray[indexPath.row];
  UICollectionViewCell * cell = [collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier forIndexPath:indexPath];

  ONHeadBtn btn = [[ONHeadBtn alloc]initWithFrame:cell.contentView.bounds];
  btn.user = user;
  // UIImageView * iconV = [[UIImageView alloc] initWithFrame:cell.contentView.bounds];
  //
  // iconV.layer.cornerRadius = iconV.width 0.5;
  //
  // iconV.layer.masksToBounds = YES;
  // iconV.image = [UIImage imageNamed:@"占位"];
  // [iconV sd_setImageWithURL:[NSURL URLWithString:user.headPicAddr]];

  for (id subView in cell.contentView.subviews) {
  [subView removeFromSuperview];
  }
  [cell.contentView addSubview:btn];
  return cell;

}

-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
self.visitorblock(indexPath.item);
}

• (void)setVisitorRecordArray:(NSArray *)visitorRecordArray{
  _visitorRecordArray = visitorRecordArray;
  [_collectionView reloadData];
  }

pragma mark 访客记录数据加载

• (void)scrollViewDidScroll:(UIScrollView *)scrollView {
  if(scrollView == self.collectionView){
  //检测左测滑动,开始加载更多
  if(scrollView.contentOffset.x +scrollView.width - scrollView.contentSize.width >30){
  NSLog(@"scrollview.contentOffset.x-->%f,scrollview.width-->%f,scrollview.contentsize.width--%f",scrollView.contentOffset.x,scrollView.width,scrollView.contentSize.width);

        if (self.indicatorView == nil) {
            UIActivityIndicatorView *indicatorView = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(scrollView.width - 20, scrollView.y + scrollView.height/2 - 10, 20, 20)];
            indicatorView.activityIndicatorViewStyle = UIActivityIndicatorViewStyleGray;
            indicatorView.hidesWhenStopped = YES;
            self.indicatorView = indicatorView;
            [self.indicatorView stopAnimating];
            [scrollView.superview addSubview:self.indicatorView];
  
        }
        if (!self.indicatorView.isAnimating) {
            scrollView.x = -30;
  
            [self.indicatorView startAnimating];
            [self loadMoreTopic];
        }
  
    }
  

  }
  }

/**

• 加载更多专题
  */

• (void)loadMoreTopic {

  self.visitorPage ++;
  NSDictionary*parameters=@{@"uuid":[CurrentUserModel sharedCurrentUserModel].uuid,@"page":@(self.visitorPage),@"pageSize":@(10)};
  [ONHttpTool POST2:queryVisitorRecordList parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {

    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)( 0.5* NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        self.collectionView.x = 0;
        [self.indicatorView stopAnimating];
    });
  
    NSInteger result = [responseObject[@"result"] integerValue];
    if (result == SUCCESS) {
        NSArray *visitorArray = responseObject[@"visitorRecordArray"];
        NSMutableArray *arrar = [NSMutableArray arrayWithArray:self.visitorRecordArray];
        [visitorArray enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
  
            VisitorRecordModel *userModel = [VisitorRecordModel userInfoWithDictionary:obj];
            [arrar addObject:userModel];
  
        }];
        self.visitorRecordArray = arrar;
        [self.collectionView reloadData];
  
    }
  

  } failure:^(AFHTTPRequestOperation *operation, NSError *error) {

    self.collectionView.x = 0;
    [self.indicatorView stopAnimating];
    [YWProgressHUD showError:@"系统繁忙"];
  

  }];

}

@end