Question

我正在使用分页来显示管理多个数据。分页适用于顶部和底部的两侧。为此，我使用下面的代码来调用API。但是当数据不大于tableView高度时，我就遇到了问题。在这种情况下，不会调用scrollViewDidEndDragging方法。所以请告诉我如何解决这个问题。当数据大于tableView高度时，下面的代码可以正常工作。

func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
    if(scrollView.panGestureRecognizer.translation(in: scrollView.superview).y > 0) {
        print("up")
        if workerInfo.count > 0 {
            let topVisibleIndexPath:IndexPath = self.tableView.indexPathsForVisibleRows![0]
            if topVisibleIndexPath.row == 0 && startCount != 0 && !isDataLoading {
                isDataLoading = true
                startCount = startCount - requiredCount
                self.callAPI(isCallFromPagination: true)
            }
         }
     }
     else {
         print("down")
         if workerInfo.count > 0 {
             let arrayOfVisibleItems = tableView.indexPathsForVisibleRows?.sorted()
             let lastIndexPath = arrayOfVisibleItems!.last
             //  print("Array: ", arrayOfVisibleItems)
             print("Last IndexPath: ", lastIndexPath as Any)
             if lastIndexPath?.row == workerInfo.count - 1 && !isDataLoading {
                 isDataLoading = true
                 startCount = startCount + requiredCount
                 self.callAPI(isCallFromPagination: true)
             }
         }
    }
}

Answer 1

可以请您检查一下此属性。在我的代码中，它可以正常工作。

extension ViewController: UIScrollViewDelegate {

func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
        print("Called")
   }
  }

Answer 2

您可以保持table view bounce和scrollview弹跳True。然后使用scrollViewDidEndDragging方法

Answer 3

// Support Pagination
extension TableViewController: UIScrollViewDelegate {

    // Set Pagination Trigger before DataSoruce remaining 6 items display
    func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {

        // Load More
        setupPaginationAt(indexPath)
    }



    // If we reached at the end, check again if anything to load
    func scrollViewWillBeginDecelerating(_ scrollView: UIScrollView) {

        let bottomEdge = scrollView.contentOffset.y + scrollView.frame.size.height
        if (bottomEdge >= scrollView.contentSize.height) {

            // We are at the end
            setupPaginationAt(nil)
        }
    }



    func setupPaginationAt(_ indexPath: IndexPath?) {

        // If any network calls on the way, we must leave - Declare a Bool variable and manipulate the value of it
        if isLoading {

            return
        }


        // Validation
        guard let _dataSource = YourDataSource else {

           print("DataSource found empty")
           return
        }



        // Config Pagination Call
        func execute() {

            // Get Current Pagination - Hope you have page index's from API
            if let currentPage = dataSource.pageIndex, let lastPage = dataSource.totalPages {

                if currentPage < lastPage {

                    let nextPage = currentPage + 1
                    loadData(at: nextPage)
                }
            }
        }


        // Check InBetween or End
        if let _indexPath = indexPath {

            if  _indexPath.row == _dataSource.count - 6 {

                execute()
            }
        } else {

            // Assume End
            execute()
        }
    }
}

此解决方案应该有效。

当数据较少时，不会在UITableview中调用scrollViewDidEndDragging

3 个答案: