Question

获得发生空指针异常的错误并尝试调用虚方法

public class after10th extends AppCompatActivity {

    ArrayAdapter<String> adapter;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.after10th);

        ListView lv = (ListView) findViewById(R.id.searchten);
        ArrayList<String> after_ten = new ArrayList<>();
        after_ten.addAll(Arrays.asList(getResources().getStringArray(R.array.after_ten)));

        adapter = new ArrayAdapter<>(after10th.this, android.R.layout.simple_list_item_1, after_ten);

        lv.setAdapter(adapter);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.menu_search, menu);
        MenuItem item = menu.findItem(R.id.menusearchten);
        SearchView searchView = (SearchView) item.getActionView();
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {

                adapter.getFilter().filter(newText);
                return false;
            }
        });

                return super.onCreateOptionsMenu(menu);`enter code here`
    }

}

这是错误：

09-23 19：09：17.242 9000-9000 / com.example.supriya.career_guidance E / AndroidRuntime：FATAL EXCEPTION：main

处理：com.example.supriya.career_guidance，PID：9000

java.lang.NullPointerException：尝试调用虚方法＆＃39; void android.widget.SearchView.setOnQueryTextListener（android.widget.SearchView $ OnQueryTextListener）＆＃39;在空对象引用上

Answer 1

错误消息几乎完全表示item.getActionView()在此行返回null：

SearchView searchView = (SearchView) item.getActionView();

获取错误空指针异常尝试调用虚方法

1 个答案: