Question

我正在使用collection View并通过API调用加载更多数据。当我从API加载更多数据时，collectionView在底部显示了活动指示器，但仅在更新现有单元格时无法添加更多collectionView单元格。

任何帮助将不胜感激。

供参考

// MARK: Delegates
extension ProdSubCat: UICollectionViewDelegateFlowLayout {

    func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
        if indexPath.row == subCatArr.count - 1 && !self.isLoading {
            loadMoreData()
        }
    }

For load more data
======================

func loadMoreData() {

        if !self.isLoading {
            self.isLoading = true
            DispatchQueue.global().async {
                // Fake background loading task for 2 seconds
                sleep(2)
                // Download more data here
                self.productSubCategories(offset: self.offsetValue, limit: 25)
                DispatchQueue.main.async {
                    self.collectionView.reloadData()
                    self.isLoading = false
                }
            }
        }
    }

 API CALL Method:
======================
 // MARK: API
    func productSubCategories(offset: Int, limit: Int) {


if response.response?.statusCode == 200 {
                    let swiftyJsonVar = JSON(response.result.value!)
                    print(swiftyJsonVar["message"].string ?? "")
                    if let category = swiftyJsonVar["product"].arrayObject {
                        if category.count != 0 {
                            self.subCatArr = category as! [[String : Any]]
                        } else {
                            self.isLoading = true
                        }
                    }
                    self.offsetValue = self.offsetValue + limit
                    print(self.offsetValue)
                    self.collectionView.reloadData()
                } else {
                    print("\(String(describing: response.request))")
                    print("Error")
                }
                ProgressHUD.dismiss()
            }
        } else {
            self.alertMessage(title: "Connectivity Error!", message: "Please connect to internet")
            ProgressHUD.dismiss()
        }
    }

Answer 1

您正在用新值（即

）替换当前数据源值

self.subCatArr = category as! [[String : Any]]

相反，您需要将数据附加到当前数组。

if let category = swiftyJsonVar["product"].arrayObject {
   if category.count != 0 {
      for obj in category { 
        self.subCatArray.append(obj)
      }
    } else {
            self.isLoading = true
      }
}

CollectionView单元重用

1 个答案: