iOS实现比例拼图的方法示例

{ "result": true, "data": { "category_sale": [ {  "name": "我是你的哥",  "sale_amount": 1,  "gross_margin_ratio": 0.22 }, {  "name": "不是亲哥哥",  "sale_amount": 4,  "gross_margin_ratio": 0 }, {  "name": "呵呵哒",  "sale_amount": 3,  "gross_margin_ratio": 0.19 }, {  "name": "因缺思厅",  "sale_amount": 2,  "gross_margin_ratio": 0.4 }] }, "msg": "ok", "code": 200, "executed": "0.0320830345"}

- (void)setModel:(CQCategoryModel *)model { _model = model;  CGFloat totalSaleAmount = 0; for (CQCategoryItemModel *itemModel in _model.category_sale) { totalSaleAmount += itemModel.sale_amount; }  for (CQCategoryItemModel *itemModel in _model.category_sale) { if (totalSaleAmount == 0) {  // 特殊处理只有一个item，并且SaleAmount还是0的情况  itemModel.ratio = 1; } else {  itemModel.ratio = itemModel.sale_amount/totalSaleAmount; } }  // 计算列数 NSInteger listCount = 0; for (int i = 0; i < _model.category_sale.count; i++) { if (i * i < _model.category_sale.count && (i+1) * (i+1) >= _model.category_sale.count) {  listCount = i+1;  break; } }  // 计算行数 NSInteger rowCount = ceil(_model.category_sale.count / (CGFloat)listCount);  // 这个方阵是listCount*rowCount的矩阵（最后一排可能不足listCount） // 同一排的cell高度相同 for (int i = 0; i < rowCount; i++) { // 行 CGFloat rowArea = 0; // 行面积 for (int j = 0; j < listCount; j++) { // 列  if (i*listCount+j>=_model.category_sale.count) {  break;  }  CQCategoryItemModel *itemModel = _model.category_sale[i*listCount+j];  itemModel.size = itemModel.ratio * (self.collectionView.width*self.collectionView.width);  rowArea += itemModel.size; } // 计算cell的宽高 for (int j = 0; j < listCount; j++) { // 列  if (i*listCount+j>=_model.category_sale.count) {  break;  }  CQCategoryItemModel *itemModel = _model.category_sale[i*listCount+j];  itemModel.height = rowArea / self.collectionView.width;  itemModel.width = itemModel.size / itemModel.height; } }  [self.collectionView reloadData];}- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath { CQCategoryItemModel *model = self.model.category_sale[indexPath.row]; // 减去0.01，避免因小数不精确存储导致一组cell宽度相加超过collectionView的宽度 return CGSizeMake(model.width-0.01, model.height);}