如何检索另一个Firebase子项中的子项（阵列）

Question

我试图从firebase打印array。实际上，如果我们点击列表中的药物（tableviewcontroller），它会显示其特定剂量。我被困住以检索剂量列表。这里是我的代码从firebase获取数据。任何帮助表示赞赏。提前致谢。我的火力结构看起来像这样.. firebase img

func loadDataFromFirebase() { 


    databaseRef = FIRDatabase.database().reference().child("medication") 


    databaseRef.observeEventType(.Value, withBlock: { snapshot in 


     for item in snapshot.children{ 
     FIRDatabase.database().reference().child("medication").child("options").observeEventType(.Value, withBlock: {snapshot in 
       print(snapshot.value) 
      }) 
     } 

    }) 

Answer 1

你应该采取火力文档https://firebase.google.com/docs/database/ios/read-and-write

看看，但如果我理解你的想法，你可能对你的药物模型类。因此，要检索数据，你应该为雨燕3.0这样做：

func loadDataFromFirebase() { 


databaseRef = FIRDatabase.database().reference().child("medication") 


databaseRef.observe(.value, with: { (snapshot) in 

    for item in snapshot.children{ 
    // here you have the objects that contains your medications 
    let value = item.value as? NSDictionary 

    let name = value?["name"] as? String ?? "" 
    let dossage = value?["dossage"] as? String ?? "" 
    let type = value?["type"] as? String ?? "" 
    let options = value?["options"] as? [String] ?? "" 

    let medication = Medication(name: name, dossage: dossage, type: type, options: options) 
    // now you populate your medications array 
    yourArrayOfMedications.append(medication) 
    } 

    yourTableView.reloadData() 
}) 
} 

现在，你有你的阵列，所有的药物，你只需要使用此药物来填充您的tableView。当有人按上表中的项目，你可以叫prepareForSegue:并发送yourArrayOfMedications[indexPath.row].options下一个视图

Answer 2

• 的解决方案是与上面相同，但有小的变化。

  func loadDataFromFirebase() { 
      databaseRef = FIRDatabase.database().reference().child("medication") 
      databaseRef.observe(.value, with: { (snapshot) in 
  
      for item in snapshot.children{ 
      // here you have the objects that contains your medications 
      let value = item.value as? NSDictionary 
  
      let name = value?["name"] as? String ?? "" 
      let dossage = value?["dossage"] as? String ?? "" 
      let type = value?["type"] as? String ?? "" 
      let options = value?["options"] as? [String : String] ?? [:] 
  
      print(options["first"]) // -> this will print 100 as per your image 
      // Similarly you can add do whatever you want with this data 
  
      let medication = Medication(name: name, dossage: dossage, type: type, options: options) 
      // now you populate your medications array 
      yourArrayOfMedications.append(medication) 
  } 
  
  yourTableView.reloadData() 
  }) 
  }