如何在android studio的导航栏标题中添加搜索字段？

<item name="android:actionBarWidgetLayout">@layout/search_view</item>

<SearchView
    android:id="@+id/searchView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:iconifiedByDefault="false"
    android:queryHint="Search"
    android:layout_gravity="center"
    android:layout_margin="8dp"
    android:background="@drawable/search_view_background"
    android:theme="@style/SearchViewStyle" />

<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="#FFFFFF" />
    <corners android:radius="8dp" />
</shape>

<style name="SearchViewStyle" parent="Widget.AppCompat.SearchView">
    <item name="android:background">@android:color/transparent</item>
    <item name="android:searchIcon">@drawable/ic_search</item>
    <item name="android:closeIcon">@drawable/ic_close</item>
    <item name="android:queryBackground">@android:color/transparent</item>
    <item name="android:queryHintTextColor">#999999</item>
    <item name="android:iconifiedByDefault">false</item>
</style>

<activity
    android:name=".YourActivity"
    android:label="@string/app_name"
    android:launchMode="singleTop">
    <meta-data
        android:name="android.app.searchable"
        android:resource="@xml/searchable" />
    <intent-filter>
        <action android:name="android.intent.action.SEARCH" />
    </intent-filter>
    <meta-data
        android:name="android.app.default_searchable"
        android:value=".YourActivity" />
</activity>

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