Android 如何将菜单设置为活动菜单？

我有这个菜单：

我是这样创造的：

菜单导航.xml

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context="com.ZZZZ.global.YYYY.XXXX">

    <item
        android:id="@+id/nearbyButton"
        android:title="Nearby"
        android:onClick="showNearbyPressed"
        android:state_selected="true"
    />

    <item
        android:id="@+id/browseAtoZButton"
        android:title="Browse A to Z"
        android:onClick="showAtoZPressed"
        android:state_selected="true"
    />

</menu>

以及：

---

关于我在这里遗漏了什么，有什么想法吗？

首先，从菜单项中删除

android:state_selected=“true”

。更新您的

菜单\u navigation.xml

，如下所示：

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context="com.ZZZZ.global.YYYY.XXXX">

    <item
        android:id="@+id/nearbyButton"
        android:title="Nearby"
        android:onClick="showNearbyPressed" />

    <item
        android:id="@+id/browseAtoZButton"
        android:title="Browse A to Z"
        android:onClick="showAtoZPressed" />

</menu>

这是

项_bg.xml

：

<android.support.design.widget.BottomNavigationView
    android:id="@+id/Navigation"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom"
    android:background="#Ccc"
    app:menu="@menu/menu_navigation"   
    app:itemIconTint="@drawable/item_bg"
    app:itemTextColor="@drawable/item_bg" />

<!-- item_bg.xml -->
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/blue" android:state_checked="true" />
    <item android:color="@color/white" />
</selector>

---

希望这会有所帮助~

为什么在两个菜单中都有

android:state\u selected=“true”

？

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context="com.ZZZZ.global.YYYY.XXXX">

    <item
        android:id="@+id/nearbyButton"
        android:title="Nearby"
        android:onClick="showNearbyPressed" />

    <item
        android:id="@+id/browseAtoZButton"
        android:title="Browse A to Z"
        android:onClick="showAtoZPressed" />

</menu>

<android.support.design.widget.BottomNavigationView
    android:id="@+id/Navigation"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom"
    android:background="#Ccc"
    app:menu="@menu/menu_navigation"   
    app:itemIconTint="@drawable/item_bg"
    app:itemTextColor="@drawable/item_bg" />

<!-- item_bg.xml -->
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/blue" android:state_checked="true" />
    <item android:color="@color/white" />
</selector>