Android SearchRecentSuggestions - 在 SearchView 中键入内容时不会显示建议

我有一个工作搜索小部件，并希望添加搜索历史记录建议。我按照Android教程（http://developer.android.com/guide/topics/search/adding-recent-query-suggestions.html）进行了操作，虽然搜索仍然有效，但没有显示任何建议。这是我的代码：

1. 内容提供商

   package com.mypackage;
   
   import android.content.SearchRecentSuggestionsProvider;
   
   public class SearchHistoryProvider extends SearchRecentSuggestionsProvider {
       public final static String AUTHORITY = SearchHistoryProvider.class.getName();
       public final static int MODE = DATABASE_MODE_QUERIES;
   
       public SearchHistoryProvider() {
           setupSuggestions(AUTHORITY, MODE);
       }
   }
   

2. 在清单中声明提供程序

   <provider 
       android:name=".SearchHistoryProvider"
       android:authorities="com.mypackage.SearchHistoryProvider">
   </provider>
   

3. 可搜索的配置

   <?xml version="1.0" encoding="utf-8"?>
   <searchable xmlns:android="http://schemas.android.com/apk/res/android"
       android:label="@string/app_name"
       android:hint="@string/search_hint"
       android:voiceSearchMode="showVoiceSearchButton|launchRecognizer"
       android:searchSuggestAuthority="com.mypackage.SearchHistoryProvider"
       android:searchSuggestSelection=" ?">
   </searchable>
   

4. 将查询保存到内容提供商（在我的可搜索活动中）

   private void handleIntent(Intent intent) {
   if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
   
       String query = intent.getStringExtra(SearchManager.QUERY);
       SearchRecentSuggestions suggestions = new SearchRecentSuggestions(this,
                           SearchHistoryProvider.AUTHORITY, SearchHistoryProvider.MODE);
       suggestions.saveRecentQuery(query, null);
   
       // Collapse the search view as a search is performed
       MenuItem searchItem = mMenu.findItem(R.id.search);
       SearchView searchView = (SearchView) mMenu.findItem(R.id.search).getActionView();
       searchItem.collapseActionView();
       searchView.setQuery("", false);
   
       // send the query to the global search activity for loading the data
       Intent globalSearchIntent = new Intent(this, GlobalSearchFragmentActivity.class);
       GroceryOTGUtils.copyIntentData(intent, globalSearchIntent);
       globalSearchIntent.putExtra(GlobalSearchFragmentActivity.GLOBAL_SEARCH, true);
       startActivity(globalSearchIntent);
   }
   }
   

一切正常，除了建议实际上并没有显示出来（搜索看起来和我添加它们之前一样）。任何帮助将不胜感激！