title: element RelativeLayout must be declared
body: <p>I'm getting the error "element <code>RelativeLayout</code> must be declared" and I don't know the reason for its occurrence. How do I get rid of this error, please post suggestions or code snippets. This is my <code>drawer_list_item.xml</code></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@id/drawer_list_item"
  android:layout_width="match_parent"
  android:layout_height="48dp"
  android:background="@drawable/list_selector"&gt;
  
  &lt;ImageView
      android:id="@+id/icon"
      android:layout_width="25dp"
      android:layout_height="wrap_content"
      android:layout_alignParentLeft="true"
      android:layout_marginLeft="12dp"
      android:layout_marginRight="12dp"
      android:contentDescription="@string/desc_list_item_icon"
      android:src="@drawable/ic_launcher"
      android:layout_centerVertical="true" /&gt;
  
  &lt;TextView
      android:id="@+id/title"
      android:layout_width="wrap_content"
      android:layout_height="match_parent"
      android:layout_toRightOf="@id/icon"
      android:minHeight="?android:attr/listPreferredItemHeightSmall"
      android:textAppearance="?android:attr/textAppearanceListItemSmall"
      android:textColor="@color/material_blue_grey_900"
      android:gravity="center_vertical"
      android:paddingRight="40dp"/&gt;
  
  &lt;TextView android:id="@+id/counter"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:background="@drawable/counter_bg"
      android:layout_alignParentRight="true"
      android:layout_centerVertical="true"
      android:layout_marginRight="8dp"
      android:textColor="@color/material_blue_grey_900"/&gt;
  
     &lt;/RelativeLayout&gt;
  </code></pre>