如何在Android中使用REST API檢索Firebase數據庫中的數據？

Question

我第一次用火的基礎工作，當我試圖用火基地的REST API，我得到這樣的迴應檢索數據，

{ 
    "-JQjT7REctmFfOAoGI6d" : { 
    "age" : "23", 
    "name" : "xxx", 
    "id" : "1" 
    }, 
    "-JQjT7RGTUdl1FTrjed6" : { 
    "age" : "34", 
    "name" : "xxx", 
    "id" : "1" 
    } 
} 

它含有不jsonarray.i想指出錯誤ID的多個JSON對象將這些數據存儲在對象中。

Answer 1

you can access data by mainly 3 ways 
1 addValueEventListener 
2 addChildEventListener 
3 addListenerForSingleValueEvent 

步驟1：創建模型類

public class UserModel { 

    String id; 
    String name; 
    String age; 

    public String getId() { 
     return id; 
    } 

    public void setId(String id) { 
     this.id = id; 
    } 

    public String getName() { 
     return name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    public String getAge() { 
     return age; 
    } 

    public void setAge(String age) { 
     this.age = age; 
    } 
} 

第2步：訪問數據在活動

Firebase firebaseUserDataReference = new Firebase("your firebase url").child("your root name/"); 

firebaseUserDataReference.addListenerForSingleValueEvent(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 

       Log.d("Call", String.valueOf(dataSnapshot.getValue())); 
       for (DataSnapshot postData : dataSnapshot.getChildren()) { 
        UserModel userModel= postData.getValue(UserModel.class); 
        yourArrayList.add(userModel); 
       }    
      } 

      @Override 
      public void onCancelled(FirebaseError firebaseError) { 

      } 
     }); 

Answer 2

如果在解析只是因爲鍵然後有問題你可以使用迭代器並提取鍵並解析它們

if(jObj != null){ 
    Iterator<Object> keys = jObj.keys(); 
    while(keys.hasNext()){ 
     String key = String.valueOf(keys.next()); // this will be your JsonObject key 
     JSONObject childObj = jObj.getJSONObject(key); 
     if(childObj != null){ 
      //Parse the data inside your JSONObject 
     } 
    } 
}