应用BottomNavigationView底栏时无法解析R.

时间:2017-09-15 15:29:08

标签: android

当我添加bottomNavigationView时,我得不到解析R,但是当我删除bottomNavigationView时错误消失了,为什么我会收到这样的错误?

以下代码结果为未解析的R

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.learn2crack.recyclerviewgrid.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/card_recycler_view"
        android:scrollbars="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

    <android.support.design.widget.BottomNavigationView
        android:id="@+id/bottom_navigation"
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:layout_alignParentBottom="true"
        android:background="@android:color/holo_blue_light"
        app:menu="@menu/my_navigation_items" />

</android.support.design.widget.CoordinatorLayout>

当删除它时,错误消失

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.learn2crack.recyclerviewgrid.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/card_recycler_view"
        android:scrollbars="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>


</android.support.design.widget.CoordinatorLayout>

1 个答案:

答案 0 :(得分:1)

如果您的XML包含错误,您生成的文件可能无法构建,请尝试删除大部分内容并确保ID不会重复。

检查您是否导入了正确的lib以使用BottomNavigation,并且您的所有道具都不为空。

这是我的活动代码:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  android:id="@+id/activity_main"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:paddingBottom="@dimen/activity_vertical_margin"
  android:paddingTop="@dimen/activity_vertical_margin"
  tools:context="MainActivity">

<android.support.design.widget.BottomNavigationView
    android:id="@+id/bottom_navigation"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    app:itemIconTint="@drawable/bottom_menu_selector"
    app:itemTextColor="@drawable/bottom_menu_selector"
    app:menu="@menu/bottom_navigation_menu" />

<ViewPager
    android:id="@+id/viewpager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_above="@id/bottom_navigation"/>