java - 在 Android 中搜索不起作用

Question

几天来，我一直在为 android 中的搜索功能而苦苦挣扎。无法查明错误。

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_exclude_list);

    .......

    SearchView searchView = (SearchView)findViewById(R.id.options_menu_main_search);
    SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    if(null!=searchManager ) {
      searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
    }

    handleIntent(getIntent());

}

@Override
public void onNewIntent(Intent intent) {
    super.onNewIntent(intent);
    setIntent(intent);
    handleIntent(intent);
}

private void handleIntent(Intent intent) {
    if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
        String query = intent.getStringExtra(SearchManager.QUERY);
        Log.i("q",query);
    }
}

searchable.xml

<searchable xmlns:android="http://schemas.android.com/apk/res/android"
 android:hint="@string/search_hint"
 android:includeInGlobalSearch="false"
 android:label="@string/app_name"
 android:searchSettingsDescription="@string/search_hint" />

菜单.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android" >
    <!-- Search, should appear as action button -->
    <item
        android:id="@+id/options_menu_main_search"
        android:actionViewClass="android.support.v7.widget.SearchView"
        android:icon="@drawable/ic_action_search"
        android:showAsAction="always"
        android:title="Search"/>
</menu>

list

<activity
 android:name="com.xyz.Exclude_list"
 android:label="@string/title_activity_exclude_list"
 android:screenOrientation="portrait"
 android:launchMode="singleTop">
 <intent-filter>
    <action android:name="android.intent.action.SEARCH" />
    <action android:name="android.intent.action.VIEW" />
 </intent-filter>

 <meta-data
  android:name="android.app.searchable"
  android:resource="@xml/searchable"
  android:value=".app.Search"
 />
</activity>

错误

Caused by: java.lang.NullPointerException
  at com.xyz.Exclude_list.onCreate(Exclude_list.java:64)

第 64 行:searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));

如果我删除

 SearchView searchView = (SearchView)findViewById(R.id.options_menu_main_search);
    SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    if(null!=searchManager ) {
      searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
    }

搜索正常，但我在搜索中输入时无法获取/记录任何查询。

Answer 1

您正在尝试在 onCreate 方法中初始化一个 MenuItem。您应该在 onCreateOptionsMenu 方法中将其初始化为:

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu, menu);
    SearchView searchView = (SearchView) menu.findItem(R.id.options_menu_main_search).getActionView();
    SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    if(null!=searchManager ) {
        searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
    }
}  

参见 Using Search Widget文档中的主题，特别是配置搜索小部件部分。此外，因为您没有使用 AppCompat 库，所以您应该使用此类(在 the docs 中声明):

android:actionViewClass="android.widget.SearchView"