Question

背景
我正在使用parse.com作为我的后端开发Android的群发消息应用程序。

工作：

我有一个ParseQueryAdapter，它使用以下命令从本地数据存储区查询ChatGroup：

public ChatGroupAdapter(final Context context) {
       super(context, new ParseQueryAdapter.QueryFactory<ChatGroup>() {
          public ParseQuery<ChatGroup> create() {
              ParseQuery<ChatGroup> chatGroupQuery = ParseQuery.getQuery(ChatGroup.class);
              chatGroupQuery.fromLocalDatastore();
              Log.d(ChatGroup.class.getName(), "Constructor query: " +  
              chatGroupQuery + " made");
              //noinspection unchecked
              return chatGroupQuery;
          }
   });
}

包含它的片段通过添加ParseQueryAdapter.OnQueryLoadListener来侦听它。如果ParseQueryAdapter无法从本地数据存储中检索ChatGroup，则会从解析中检索它，将其固定，然后触发ParseQueryAdapter以使用以下命令从本地数据存储重试加载：{{1 }}。这是我的片段中的代码片段：
```
.loadObjects();
```

结果：
这是一个简化的执行日志：

@Override
    public void onLoaded(List<ChatGroup> groups, Exception e) {
        l.d("onLoaded called");
        if (e != null) {
            e.printStackTrace();
            updateLocalDatastore();
        } else if (groups == null) {
            l.w("Received null group list.");
            updateLocalDatastore();
        } else if (groups.size() == 0) {
            l.w("Received group list of size zero.");
            updateLocalDatastore();
        } else {
            l.d("Chat groups loaded successfully");
        }
    }

private void updateLocalDatastore() {
    final ParseQuery<ChatGroup> groupQuery = ParseQuery.getQuery(ChatGroup.class);
    groupQuery.findInBackground(new FindCallback<ChatGroup>() {
        @Override
        public void done(final List<ChatGroup> chatGroupList, ParseException e) {
            if (e != null) {
                e.printStackTrace();
            } else {
                if (chatGroupList != null) {
                    ParseObject.pinAllInBackground(chatGroupList, new SaveCallback() {
                        @Override
                        public void done(ParseException e) {
                            if (e != null) {
                                e.printStackTrace();
                            } else {
                                l.d("Successfully pinned: " + chatGroupList.size() +
                                        " groups to local datastore. Reloading adapter");
                                groupAdapter.loadObjects();
                            }
                        }
                    });
                } else {
                    l.e("Received null group list from cloud! " +
                            "Local datastore update failed!");
                }
            }
        }
    });
}

我很明显ChatFragment: onCreate ChatFragment﹕ Initializing chat groups ChatFragment﹕ Loading chat groups ChatFragment: onStart ChatFragment: onResume ChatFragment﹕ onLoaded called ChatFragment﹕ Received group list of size zero. ChatFragment﹕ Successfully pinned: 3 groups to local datastore. Reloading adapter ChatFragment﹕ Loading chat groups ChatFragment﹕ onLoaded called ChatFragment﹕ Received group list of size zero. ChatFragment﹕ Successfully pinned: 3 groups to local datastore. Reloading adapter ChatFragment﹕ Loading chat groups ChatFragment﹕ onLoaded called ChatFragment﹕ Received group list of size zero. ChatFragment﹕ Successfully pinned: 3 groups to local datastore. Reloading adapter ChatFragment﹕ Loading chat groups ChatFragment﹕ onLoaded called ChatFragment﹕ Received group list of size zero.应该首次检索0列表，触发ParseQueryAdapter从解析中提取3 updateLocalDatastore()，然后将它们固定从本地数据存储区收到3。 但是，如日志所示，即使成功固定后，它仍会从本地数据存储中找到0 ChatGroup个！

项目设置似乎很好：

ChatGroup

我做错了什么？！我错过了什么吗？

我用Parse.enableLocalDatastore(this); Parse.initialize(this, AppProps.properties.appId, AppProps.properties.clientKey); ParseUser.enableRevocableSessionInBackground(); Parse.setLogLevel(Parse.LOG_LEVEL_DEBUG); ParseObject.registerSubclass(ChatGroup.class);实现了完全相同的逻辑，它运行得很完美！使用ParseUser执行相同操作似乎有问题：

GroupChat

有人说它是在本地数据存储区中具有关系的解析bug。但我甚至没有使用关系。即使来自本地数据存储区的简单查询也不起作用。

Answer 1

虽然我无法解决问题，但我发现了问题所在。该问题与Android的Parse SDK的基本错误有关：ParseQuery gives 0 objects when querying from local datastore even after successfully pinning

使用ParseQueryAdapter查询本地数据存储区即使成功固定后也会得到0结果

1 个答案: