选择商品规格.gif
由实现选规格的效果来记录下所用到的基础控件和知识点
控件： UIcollectionview
- 初始化
//初始化布局
UICollectionViewFlowLayout *layout=[[UICollectionViewFlowLayout alloc] init];
layout.scrollDirection=UICollectionViewScrollDirectionVertical;//竖直滚动
layout.minimumInteritemSpacing=0;//itme左右间距
layout.minimumLineSpacing=10;//itme 上下间距
//section 距上下左右的距离
layout.sectionInset=UIEdgeInsetsMake(0, 10, 0, 10);
//头部的size
layout.headerReferenceSize = CGSizeMake(kScreenWidth, 20);
_collectionview.collectionViewLayout = layout;
_collectionview.dataSource=self;
_collectionview.delegate=self;
_collectionview.backgroundColor=[UIColor whiteColor];
//支持分页
_collectionview.pagingEnabled=NO;
_collectionview.scrollEnabled=NO;
//注册cell
[_collectionview registerNib:[UINib nibWithNibName:@"TSChooseSpeciColleCell" bundle:nil] forCellWithReuseIdentifier:@"TSChooseSpeciColleCell"];
//注册组头
UINib *headerNib = [UINib nibWithNibName:@"TSSpeciColleHead" bundle:nil];
[_collectionview registerNib:headerNib forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"TSSpeciColleHead"];
- collectionView的代理和数据源方法
- 有几组
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{
return self.contentarry.count;
}
- 每组有几个cell
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
self.parammodel=self.contentarry[section];
return self.parammodel.attr_values.count;
}
- 加载自定义cell
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
TSChooseSpeciColleCell *cell=[collectionView dequeueReusableCellWithReuseIdentifier:@"TSChooseSpeciColleCell" forIndexPath:indexPath];
return cell;
}
- 点击cell响应
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
}
- 动态设置每个itme大小，根据文字字号大小自适应宽度。
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{
self.parammodel=self.contentarry[indexPath.section];
self.valuemodel = [TSvaluesmodel mj_objectWithKeyValues: self.parammodel.attr_values[indexPath.row]];
CGSize size = [NSString sizeWithText:self.valuemodel.attr_value font:[UIFont systemFontOfSize:20] maxW:kScreenWidth - 30];
return size;
}
- 计算文字返回size的方法
//根据文字和字体的大小计算文字的容器的大小
+ (CGSize)sizeWithText:(NSString *)text font:(UIFont *)font maxW:(CGFloat)maxW
{
NSMutableDictionary *attrs = [NSMutableDictionary dictionary];
attrs[NSFontAttributeName] = font;
CGSize maxSize = CGSizeMake(maxW, MAXFLOAT);
//约束宽度
return [text boundingRectWithSize:maxSize options:NSStringDrawingUsesLineFragmentOrigin attributes:attrs context:nil].size;
}
- 加载自定义的collectview的Footer或者Header
- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
{
//继承自UICollectionReusableView ，返回的要是这个类型才可以，和cell一样有重用机制
TSSpeciColleHead *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"TSSpeciColleHead" forIndexPath:indexPath];
self.parammodel=self.contentarry [indexPath.section];
headerView.titleLab.text = self.parammodel.attr_name;
return headerView;
}
实现多行单选效果
实现思路
每一组只能选中一个，选择同行的会恢复上一次选中的状态，显示最新选中的cell的选中状态，每组不影响单独控制每一组，所以有几组就存几个状态值，要想要每每准确对应改变之前所选的值，那么就用字典的特性，用key找到它改掉它，成为最新的状态。
实现: 用section当key 用row当value,存一个字典，改变选中的状态自动覆盖前一个值
NSString *rowstr =[NSString stringWithFormat:@"%ld",indexPath.row];
NSString *sectstr =[NSString stringWithFormat:@"section%ld",indexPath.section];
[self.Mudic setValue:rowstr forKey:sectstr];
