为什么我的滚动在 iOS Swift 中的 iPhone 12 和 iPhone 11 上不起作用

overrIDe func vIEwDIDLoad() {
 super.vIEwDIDLoad()
 // using framework
 let bottomrefreshController = UIrefreshControl()
 bottomrefreshController.triggerVerticalOffset = 50
 bottomrefreshController.addTarget(self,action: #SELEctor(refresh),for: .valueChanged)
 self.collectionVIEw.bottomrefreshControl = bottomrefreshController
 self.collectionVIEw.bottomrefreshControl?.Tintcolor = .clear
 }


 @objc func refresh() {
 serviceCall()
 }


  fileprivate func allProductsserviceCall(){

 let param = ["params": ["category" : catID,"sub_category" : self.subCatID,"brands": brands,"count" : self.currentPagenumber

              ]] as [String : Any]
 APIReqeustManager.sharedInstance.serviceCall(param: param,vc: self,url: getUrl(of: .all_products/*.search*/),header: header) {(responseData) in
     
     if responseData.error != nil{
         self.vIEw.maketoast(NSLocalizedString("Something went wrong!",comment: ""))
     }else{
         if (SearchDataModel(Dictionary: responseData.Dict as NSDictionary? ?? NSDictionary())?.result?.products ?? [Products]()).count == 0 {
             self.vIEw.maketoast("No product to show!".localizeWithLanguagE)
             return
         }
         if self.currentPagenumber > 0 {
             if (SearchDataModel(Dictionary: responseData.Dict as NSDictionary? ?? NSDictionary())?.result?.products ?? [Products]()).count > 0 {
                 self.searchResultData?.result?.products! += SearchDataModel(Dictionary: responseData.Dict as NSDictionary? ?? NSDictionary())?.result?.products ?? [Products]()
             }else {
                 self.vIEw.maketoast("No more products to show!".localizeWithLanguagE)
             }
             
             self.productCollectionVIEw.bottomrefreshControl?.endrefreshing()
       
         self.currentPagenumber+=1
         
         dispatchQueue.main.async{
         self.productCollectionVIEw.reloadData()
         }
     }
 }
 }


// Scroll delegates
// Things needed for expand / collapse
func scrollVIEwDIDScroll(_ scrollVIEw: UIScrollVIEw) {

if scrollVIEw == productCollectionVIEw {
    let delta = scrollVIEw.contentOffset.y - lastContentOffset
    if Delta < 0 {
        // move up
        if scrollVIEw.contentOffset.y <= (-self.range.lowerBound) {
            print("at the top")
            self.productCollectionVIEw.bounces = false
            topConsTraint.constant = min(topConsTraint.constant - (delta),range.upperBound)
        }else {
            print("at the mIDdle,moving up")
        }
    } else {
        // move down
        topConsTraint.constant = max(range.lowerBound,topConsTraint.constant - (delta))
        if (scrollVIEw.contentOffset.y + scrollVIEw.frame.size.height) == scrollVIEw.contentSize.height {
          print("at the end")
            self.productCollectionVIEw.bounces = true
        }else {
          print("at the mIDdle,moving down")
        }
    }
    lastContentOffset = scrollVIEw.contentOffset.y
}
}
@H_874_8@