Android的火力地堡從數據庫

Question

閱讀ArrayList對象。當我上傳對象的ArrayList在我與的setValue火力數據庫，

有人以這種方式存儲：database screenshot

而現在我想知道如果我能找回這ArrayList從數據庫中使用其中的信息來填充列表視圖。

public class Alarm { 

    private String alarm_time; 
    private String alarm_ampm; 
    private String alarm_days; 

    public void setAlarm_time(String time) { 
     alarm_time = time; 
    } 

    public void setAlarm_ampm(String ampm) { 
     alarm_ampm = ampm; 
    } 

    public void setAlarm_days(String days) { 
     alarm_days = days; 
    } 

    public String getTime() { 
     return this.alarm_time; 
    } 

    public String getAmpm() { 
     return this.alarm_ampm; 
    } 

    public String getDays() { 
     return this.alarm_days; 
    } 
} 

這就是Alarm的樣子，報警存儲在我上傳到數據庫的ArrayList中。

有沒有辦法直接從Firebase數據庫檢索ArrayList？還是有任何圖書館可以幫助我？

Answer 1

試試這個

private void getAlarmLlist() { 
     final List<Alarm> alarmList=new ArrayList(); 
     DatabaseReference databaseReference = FirebaseDatabase.getInstance().getReference().child("alarm_list"); 
     databaseReference.addListenerForSingleValueEvent(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       try { 
        for (DataSnapshot postSnapshot : dataSnapshot.getChildren()) { 
         Alarm alarm= postSnapshot.getValue(Alarm.class); 
         alarmList.add(alarm); 
        } 
       } catch (Exception e) { 
        e.printStackTrace(); 
       } 
      } 

      @Override 
      public void onCancelled(DatabaseError databaseError) { 
       Log.w(TAG, "Error: ", databaseError.toException()); 
      } 
     }); 
    }