长沙零基础学快速建站,工会网站群建设方案,做货代用什么网站找客户,孝感网站开发不知道写了多少次collectionview#xff0c;步了很多坑#xff0c;现在看来虽然达到了自己想要的结果#xff0c;却不知道其中所以然。还是总结一下#xff0c;免得再走弯路#xff1b; 场景是这样的#xff0c;我要定制一个显示选择图片的排列#xff0c;想要实现横向排…不知道写了多少次collectionview步了很多坑现在看来虽然达到了自己想要的结果却不知道其中所以然。还是总结一下免得再走弯路 场景是这样的我要定制一个显示选择图片的排列想要实现横向排列4个等间距多了折行显示的效果正确的做法是这样的 - (void)viewDidLoad {[super viewDidLoad];self.navigationController.navigationBar.translucent NO;if ([self respondsToSelector:selector(setAutomaticallyAdjustsScrollViewInsets:)]) {self.automaticallyAdjustsScrollViewInsets NO;}self.view.backgroundColor [UIColor purpleColor];self.photoArray [[UIImage imageNamed:cycle3],[UIImage imageNamed:cycle4],[UIImage imageNamed:cycle2],[UIImage imageNamed:cycle3],[UIImage imageNamed:cycle4],].mutableCopy;[self.view addSubview:self.pickPhotoCollection];
}-(UICollectionView *)pickPhotoCollection{if (!_pickPhotoCollection) {UICollectionViewFlowLayout *layout [[UICollectionViewFlowLayout alloc]init];layout.scrollDirection UICollectionViewScrollDirectionVertical;_pickPhotoCollection [[UICollectionView alloc]initWithFrame:CGRectMake(0, 200, kScreenWidth, (self.photoArray.count/4 1)*80) collectionViewLayout:layout];_pickPhotoCollection.delegate self;_pickPhotoCollection.dataSource self;_pickPhotoCollection.backgroundColor RGBACOLOR(240, 240, 240, 1);_pickPhotoCollection.showsHorizontalScrollIndicator NO;[_pickPhotoCollection registerClass:[XJPickPhotoCollectionViewCell class] forCellWithReuseIdentifier:NSStringFromClass([XJPickPhotoCollectionViewCell class])];}return _pickPhotoCollection;
}
-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{return 1;
}-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{return self.photoArray.count 1 9 ? 9 : self.photoArray.count 1;
}-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{XJPickPhotoCollectionViewCell *cell (XJPickPhotoCollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:NSStringFromClass([XJPickPhotoCollectionViewCell class]) forIndexPath:indexPath];//判断图片的显示方式 如果不是9张图 则显示可以继续添加if (self.photoArray.count 9) {cell.photoImageView.image self.photoArray[indexPath.row];return cell;}if (indexPath.row self.photoArray.count) {cell.photoImageView.image [UIImage imageNamed:addPhoto];}else{cell.photoImageView.image self.photoArray[indexPath.row];}return cell;
}-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{return CGSizeMake(WidthScale(70), WidthScale(70));
}
-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section{
// return 2;return (kScreen_width - WidthScale(70)*4 - 10 )/3.;
}
//-(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section{
// return (kScreen_width - WidthScale(70)*4 - 10 )/3.;
//}
-(UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{return UIEdgeInsetsMake(5, 5, 5, 5);
} 关键点在这里 1-layout.scrolldirection uicollectionViewScrollDirectionVertical;collection的滚动方向由于要折行向下所以方向是垂直方向在排列的时候会默认选择先将横向排列完毕折行向下。 2-- minmumlinespaceing 这个这个属性用来指示行与行之间的最小距离(纵向)或者列与列之间的最小距离(横向)。无论横向或者纵向都可以滚动显示所有内容所以这个属性可以单独设置。 SO 在不同的滚动方向上要分清楚他的作用我就是在这里弄的头晕目眩 当然interitem就很好理解了 另外还有一点是 如果是自定义的layoutlayout的代理方法是不会执行的若想达到相同的效果需要在自定义的layout内部进行处理 layout.scrollDirection UICollectionViewScrollDirectionVertical; 转载于:https://www.cnblogs.com/lidarui/p/6931415.html
