创建UICollectionViewFlowLayout 对象来设置相关的布局，包括itemSize，headerReferenceSize，sectionInset。设置对应的布局大小，相关的和顶部之间的间距等。
UICollectionView创建对应的view并且定义对应的大小，设置代理方法和数据源对象。
-(void)loadCollectionView
{
UICollectionViewFlowLayout * collectionViewFlow = [[UICollectionViewFlowLayout alloc]init];
UICollectionView *collectView = [[UICollectionView alloc]initWithFrame:CGRectMake(, ScreenHeight, CGRectGetWidth(_homeScrollView.frame), )collectionViewLayout:collectionViewFlow]; collectView.dataSource = self;
collectView.delegate = self;
collectView.backgroundColor = [UIColor blueColor];
[collectView registerClass:[CSHomeCollectionViewCell class] forCellWithReuseIdentifier:@"collectionCell"];
collectionViewFlow.itemSize = CGSizeMake(, );
collectionViewFlow.sectionInset = UIEdgeInsetsMake(, , , );
collectionViewFlow.scrollDirection = UICollectionViewScrollDirectionVertical;
[_homeScrollView addSubview:collectView];
}
//datasource,delegate
-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
return ;
}
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
CSHomeCollectionViewCell * cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"collectionCell" forIndexPath:indexPath];
cell.topImage.image = [UIImage imageNamed:@"cludy_bg"];
return cell;
}
从而来实现对应的方法，其中自定义的cell类
-(instancetype)initWithFrame:(CGRect)frame
{
self =[super initWithFrame:frame];
if (self) {
self.backgroundColor = [UIColor grayColor];
self.topImage = [[UIImageView alloc]initWithFrame:CGRectMake(, , MYSIZE.width-, MYSIZE.height*0.6)];
[self addSubview:_topImage]; self.designer = [[UILabel alloc]initWithFrame:CGRectMake(, CGRectGetHeight(self.topImage.frame), CGRectGetWidth(self.frame), )]; self.designer.text = @"hello";
[self addSubview:_designer]; // self.goodBtn = [UIButton alloc]initWithFrame:CGRectMake(0, <#CGFloat y#>, <#CGFloat width#>, <#CGFloat height#>) }
return self;
}
当定义的时候，自动调用initwithframe函数来初始化