Question

我使用firebase创建To-Do android应用程序。我使用recyclerview和cardview来填充firebase的数据。但是当我在Android Monitor上观看并看到我的调试日志触发两次onChildChanged时，会发生一些奇怪的事情：

D/DiaryAdapter: onChildChanged:-KIafq035E-pc6uT3Ej7
D/DiaryAdapter: onChildChanged:-KIafq035E-pc6uT3Ej7

并且在recyclerview上导致的项目闪烁两次（当项目更新时闪烁效果）

我把它放在MainFragment.java onStart()

上

        // Setup adapter
        diaryAdapter = new DiaryAdapter(getContext(),mDiaryRef);

        recyclerDiary.setAdapter(diaryAdapter);

在我的适配器构造函数

上

public DiaryAdapter(final Context context, DatabaseReference ref) {
 mContex = context;
 mDatabaseRefrence = ref;


 mChildEventListener = new ChildEventListener() {
  @Override
  public void onChildAdded(DataSnapshot dataSnapshot, String s) {
   //Log.d(TAG, "onChildAdded:" + dataSnapshot.getKey());

   Diary diary = dataSnapshot.getValue(Diary.class);
   mDiary.add(diary);
   mDiaryID.add(dataSnapshot.getKey());
   notifyItemInserted(mDiary.size() - 1);

  }

  @Override
  public void onChildChanged(DataSnapshot dataSnapshot, String s) {
   Log.d(TAG, "onChildChanged:" + dataSnapshot.getKey());

   Diary newDiary = dataSnapshot.getValue(Diary.class);

   int diaryIndex = mDiaryID.indexOf(dataSnapshot.getKey());

   if (diaryIndex > -1) {
    mDiary.set(diaryIndex, newDiary);
    notifyItemChanged(diaryIndex);
   } else {
    Log.w(TAG, "onChildChanged:unknown_child:" + dataSnapshot.getKey());
   }
  }

  @Override
  public void onChildRemoved(DataSnapshot dataSnapshot) {
   Log.d(TAG, "onChildRemoved:" + dataSnapshot.getKey());

   int diaryIndex = mDiaryID.indexOf(dataSnapshot.getKey());

   if (diaryIndex > -1) {
    mDiary.remove(diaryIndex);
    mDiaryID.remove(diaryIndex);

    notifyItemRemoved(diaryIndex);
   } else {
    Log.w(TAG, "onChildRemoved:unknown_child:" + dataSnapshot.getKey());
   }
  }

  @Override
  public void onChildMoved(DataSnapshot dataSnapshot, String s) {
   Log.d(TAG, "onChildMoved:" + dataSnapshot.getKey());
  }

  @Override
  public void onCancelled(DatabaseError databaseError) {
   Log.w(TAG, "postComments:onCancelled", databaseError.toException());
   Toast.makeText(mContex, "Failed to load diary.",
    Toast.LENGTH_SHORT).show();
  }
 };

 ref.addChildEventListener(mChildEventListener);
}

我跟随firebase android示例here

编辑：数据库结构

{
  "diary" : {
    "2Y4XwraNoRdIFPBJY0XxwdPte0H2" : {
      "1437" : {
        "-KIahAPVU_WrmP5rDcAa" : {
          "created" : 1464159484316,
          "infaq" : {
            "selesai" : false
          },
          "ngaji" : {
            "ayatAkhir" : 0,
            "ayatMulai" : 0,
            "selesai" : true,
            "surahAkhir" : 0,
            "surahMulai" : 0
          },
          "puasa" : {
            "sahur" : false,
            "selesai" : true,
            "summary" : ""
          },
          "sholat" : {
            "ashar" : true,
            "dhuhur" : true,
            "done" : true,
            "mIsya" : true,
            "maghrib" : true,
            "subuh" : true
          },
          "summary" : "Puasa kedua Tos",
          "tanggal" : 2,
          "tarawih" : {
            "ringkasan" : "",
            "selesai" : true
          },
          "updated" : 1464186194796
         },
        }
    }
}

Firebase ChildEventListener onChildChanged触发了两次

0 个答案: