獲取RuntimeException：二進制XML文件行：您必須提供一個layout_width屬性。屬性缺失在哪裏？

Question

即時得到以下運行時錯誤：

android.view.InflateException: Binary XML file line #24: Binary XML file line #15: You must supply a layout_width attribute. 

我檢查了我的代碼多次，但我找不到在哪裏我錯過了layout_width屬性的任何地方。哪裏有問題？

item.xml：

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:orientation="vertical" 
android:layout_width="match_parent" 
android:layout_height="match_parent"> 

<TextView 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:layout_alignParentTop="true" 

    android:id="@+id/myDate"/> 


<TextView 
    android:layout_below="@id/myDate" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:id="@+id/myTime"/> 

</RelativeLayout> 

activity_main.xml中

<?xml version="1.0" encoding="utf-8"?> 
<android.support.design.widget.CoordinatorLayout 
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" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:fitsSystemWindows="true" 
tools:context="com.example.nirvan.recyclerview.MainActivity"> 

<android.support.design.widget.AppBarLayout 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:theme="@style/AppTheme.AppBarOverlay"> 



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

<include layout="@layout/content_main" /> 



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

content_main.xml

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout 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" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:paddingBottom="@dimen/activity_vertical_margin" 
android:paddingLeft="@dimen/activity_horizontal_margin" 
android:paddingRight="@dimen/activity_horizontal_margin" 
android:paddingTop="@dimen/activity_vertical_margin" 
app:layout_behavior="@string/appbar_scrolling_view_behavior" 
tools:context="com.example.nirvan.recyclerview.MainActivity" 
tools:showIn="@layout/activity_main"> 

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




</RelativeLayout> 

Answer 1

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

應該是

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