swift - 如何通过实时按下按钮来过滤数据

Question

我正在从 firebase 检索数据，并且我有几个按钮来过滤数据。此功能正在运行，但要查看过滤结果，我必须退出并重新打开应用程序。这是我的代码：

self.ItemRef.observe(.value, with: { (snapshot) in
   var updatedItem = [MyItem]()
   for user_child in (snapshot.children) {
                    
       let user_snap = user_child as! DataSnapshot
       let dict = user_snap.value as! [String: Any]
    
       guard let category = dict["category"] as? String else { return}
       var item =  MyItem.init(image1: ItemImage1, image2: "", image3: "",
                               image4: "", image5: "", name: ItemName,
                               details: "", size: "", price: price,
                               gender: "", category: category)
      if item.category == filteredCategory {
         updatedItem.append(item)
      }
   }
   self.itemList = updatedItem
 })

标签： swiftfirebase-realtime-databasefilter