Question

我收到以下错误：

java.lang.NullPointerException：尝试在第28行的空对象引用上调用虚方法'void android.widget.SearchView.setSearchableInfo（android.app.SearchableInfo）'

此代码来自android开发者网站https://developer.android.com/training/search/setup.html#add-sv

菜单/ options_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/search"
        android:title="Seach now"
        android:icon="@drawable/searchicon"
        android:showAsAction="collapseActionView|ifRoom"
        android:actionViewClass="android.widget.SearchView" />
</menu>

searchable.xml

<?xml version="1.0" encoding="utf-8"?>

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

主要活动

public class MainActivity extends AppCompatActivity {

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

    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.options_menu, menu);

        // Associate searchable configuration with the SearchView
        SearchManager searchManager =
                (SearchManager) getSystemService(Context.SEARCH_SERVICE);
        SearchView searchView =
                (SearchView) menu.findItem(R.id.search).getActionView();
        searchView.setSearchableInfo(
                searchManager.getSearchableInfo(getComponentName()));

        return true;
    }
}

清单

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.agoogler.rafi.search_test2">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
            <meta-data android:name="android.app.searchable"
                android:resource="@xml/searchable" />

        </activity>
    </application>

</manifest>

Answer 1

只需将其替换为菜单文件

即可

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
    android:id="@+id/action_search"
    android:icon="@drawable/disha"
    app:showAsAction="collapseActionView|always"
    android:title="search"
    app:actionViewClass="android.support.v7.widget.SearchView"/>



  </menu>

和java代码

public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.search_menu, menu);

    // Associate searchable configuration with the SearchView
    SearchManager searchManager =
            (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    SearchView searchView =
            (SearchView) menu.findItem(R.id.action_search).getActionView();
    searchView.setSearchableInfo(
            searchManager.getSearchableInfo(getComponentName()));

    return true;
}

或尝试此

如果您想在应用栏中添加搜索视图，可以尝试使用

 getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    getSupportActionBar().setCustomView(R.layout.search_layout);

    search = (EditText) getSupportActionBar().getCustomView().
            findViewById(R.id.searchfield);

    search.setOnEditorActionListener(new EditText.OnEditorActionListener() {
        @Override
        public boolean onEditorAction(TextView v, int actionId,
                                      KeyEvent event) {
            return true;
        }
    });

    getSupportActionBar().setDisplayOptions(getSupportActionBar().DISPLAY_SHOW_CUSTOM
            | getSupportActionBar().DISPLAY_SHOW_HOME);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

比为此创建自定义布局

<?xml version="1.0" encoding="utf-8"?>
<EditText xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/searchfield"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/custom_search_edit"
android:hint="@string/search_hint"
android:inputType="textFilter"
android:textColor="@color/colorBlack"
android:textColorHint="@color/colorAccent"
android:textSize="15sp" />

Answer 2

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">

<item
    android:id="@+id/miActionButton"
    app:showAsAction="ifRoom"
    app:actionLayout="@layout/etLayout"
    android:title="Loading..."/>

</menu>

在布局文件夹中创建etLayout XML

<?xml version="1.0" encoding="utf-8"?>
<EditText xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/search"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="@string/search_hint"
android:inputType="textFilter" />

将搜索视图添加到App Bar- null对象引用错误

2 个答案: