无法转换为 android.app.Activity ：尝试将搜索添加到片段时

Question

我正在努力完成一项任务，即使我已经阅读了相同的其他主题，我也遇到了极大的困难。

情况

我有一个从导航模板构建的程序，我正在尝试添加搜索功能。我已经通过使用活动的应用程序完成了这项任务，但我无法使用片段重新创建它。

问题

当我尝试搜索时，我得到了错误。

java.lang.RuntimeException：无法实例化活动 组件信息{.MySearchableActivity}： java.lang.ClassCastException： .MySearchableActivity 无法转换为 android.app.Activity

我相信这已经完成，因为我在片段中调用了一个意图，但是我不确定我还能如何实现它。

public class MySearchableActivity extends Fragment {
    RequestQueue requestQueue;
    List<NumberResults> storiesList = new ArrayList<>();
    private RecyclerView recycle;


    private static final String TAG = "junk";
    private Toolbar toolbar;
    private ListView myList;
  //  final Context context = this;

    //  @Override
    //protected void onCreate(Bundle savedInstanceState)
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        //super.onCreate(savedInstanceState);
        // setContentView(R.layout.fragment_ministry_numbers);

      //  toolbar = (Toolbar) findViewById(R.id.app_bar);
     //   setSupportActionBar(toolbar);
        Log.i(TAG, "in MySearchableActivity");


        View layout = inflater.inflate(R.layout.fragment_ministry_numbers, container, false);
        recycle = (RecyclerView) layout.findViewById(R.id.drawrList);
        recycle.setLayoutManager(new LinearLayoutManager(getActivity()));
        recycle.setHasFixedSize(true);


        Intent intent = getActivity().getIntent();
        handleIntent(intent);

        return layout;
    }

    private void handleIntent(Intent intent) {
        // get the query out of the intent
        if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
            String searchQuery = intent.getStringExtra(SearchManager.QUERY);
            doSearchQuery(searchQuery);
        }

    }
     /*
    @Override
    protected void onNewIntent(Intent intent) {
        Log.i(TAG, "in onNewIntent");
        getActivity().setIntent(intent);
        handleIntent(intent);
    }
*/

    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        super.onCreateOptionsMenu(menu, inflater);
        menu.clear();
        inflater.inflate(R.menu.main, menu);
        MenuItem item = menu.findItem(R.id.searchActionBarItem);
        SearchView searchView = (SearchView) MenuItemCompat.getActionView(item);
        MenuItemCompat.setShowAsAction(item, MenuItemCompat.SHOW_AS_ACTION_COLLAPSE_ACTION_VIEW | MenuItemCompat.SHOW_AS_ACTION_IF_ROOM);
        MenuItemCompat.setActionView(item, searchView);
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                return false;
            }
            @Override
            public boolean onQueryTextChange(String newText) {
                return false;
            }
        });
        searchView.setOnClickListener(new View.OnClickListener() {
                                          @Override
                                          public void onClick(View v) {

                                          }
                                      }
        );
    }


    private void doSearchQuery(String query) {

        final MinNumAdapters rvAdapter = new MinNumAdapters(storiesList);
        recycle.setAdapter(rvAdapter);


        requestQueue = Volley.newRequestQueue(getActivity());
        String url = "http://werver.com/searchablewho.php?owner=" + query;


        JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(url, new Response.Listener<JSONArray>() {
            @Override
            public void onResponse(JSONArray response) {
                try {
                    if (response.length() > 0) {
                        storiesList.clear();
                        for (int i = 0; i < response.length(); i++) {
                            JSONObject jsonObject = response.getJSONObject(i);
                            NumberResults stories = new NumberResults();

                            if (!jsonObject.isNull("number")) {
                                stories.name = jsonObject.getString("number");
                            }
                            if (!jsonObject.isNull("owner")) {


                                stories.age = jsonObject.getString("owner");



                            }
                            storiesList.add(i, stories);
                        }
                        rvAdapter.notifyDataSetChanged();
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                // do something
            }
        });

        requestQueue.add(jsonArrayRequest);

    }

}

堆栈跟踪

11-17 17:15:00.308 18802-18802/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: technologies.mirage.prigovdirectory, PID: 18802
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{technologies.mirage.prigovdirectory/technologies.mirage.prigovdirectory.MinNumResults.MySearchableActivity}: java.lang.ClassCastException: technologies.mirage.prigovdirectory.MinNumResults.MySearchableActivity cannot be cast to android.app.Activity
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2236)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
    at android.app.ActivityThread.access$800(ActivityThread.java:151)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:135)
    at android.app.ActivityThread.main(ActivityThread.java:5254)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.ClassCastException: technologies.mirage.prigovdirectory.MinNumResults.MySearchableActivity cannot be cast to android.app.Activity
    at android.app.Instrumentation.newActivity(Instrumentation.java:1066)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2226)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) 
    at android.app.ActivityThread.access$800(ActivityThread.java:151) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:135) 
    at android.app.ActivityThread.main(ActivityThread.java:5254) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at java.lang.reflect.Method.invoke(Method.java:372) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 

调用搜索

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    //getMenuInflater().inflate(R.menu.main, menu);


    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);


    SearchManager searchManager =
            (SearchManager) getSystemService(Context.SEARCH_SERVICE);

    MenuItem searchActionBarItem = menu.findItem(R.id.searchActionBarItem);

    SearchView searchView = (SearchView) MenuItemCompat.getActionView(searchActionBarItem);
    searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
    searchView.setIconifiedByDefault(true);


    return true;
}

应用清单

<uses-permission android:name="android.permission.CALL_PHONE"/>
<uses-permission android:name="android.permission.INTERNET" />
<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:theme="@style/AppTheme.NoActionBar">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <action android:name="android.intent.action.SEARCH"/>
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
        <meta-data
            android:name="android.app.default_searchable"
            android:value=".MinNumResults.MySearchableActivity"/>
    </activity>



    <activity
        android:name=".MinNumResults.MySearchableActivity"
        android:label="@string/app_name"
        android:launchMode="singleTop">
        <intent-filter>
            <action android:name="android.intent.action.SEARCH"/>
        </intent-filter>
        <meta-data
            android:name="android.app.searchable"
            android:resource="@xml/search_config"/>
    </activity>
</application>

Answer 1

将 Fragment 命名为 Activity 不起作用：您不能将 Fragment 用作 Activity 并在 AndroidManifest 中用作可搜索的。

您必须阅读thread。希望，这将帮助您找到正确的方法。总账