title: No resource identifier found for attribute 'layout_alignParentCenter' in package 'android'
body: <p>I'm getting two errors when attempting to add a scrollable navigation bar to the bottom of my screen. I've never seen this error before and the answers I've found thus far do not seem to resolve the issue I'm having. </p>
  
  <h2>ERRORS:</h2>
  
  <pre><code>error: No resource identifier found for attribute 'layout_alignParentCenter' in package 'android'   home.xml    /idg/res/layout line 298    Android AAPT Problem
  error: No resource identifier found for attribute 'layout_alignParentCenter' in package 'android'   home.xml    /idg/res/layout line 361    Android AAPT Problem
  </code></pre>
  
  <p>Any input is greatly appreciated.</p>
  
  <h2>XML SOURCE:</h2>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/drawer_layout"
      android:layout_width="match_parent"
      android:layout_height="match_parent" &gt;
  
      &lt;!-- The main content view --&gt;
  
      &lt;LinearLayout
          android:id="@+id/content_frame"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:orientation="vertical" &gt;
  
          &lt;!-- The rest of your layout (TextView, ScrollView, etc) --&gt;
  
      &lt;/LinearLayout&gt;
  
      &lt;!-- The navigation drawer --&gt;
  
      &lt;ListView
          android:id="@+id/left_drawer"
          android:layout_width="240dp"
          android:layout_height="match_parent"
          android:layout_gravity="start"
          android:background="#111"
          android:choiceMode="singleChoice"
          android:divider="@android:color/transparent"
          android:dividerHeight="0dp" /&gt;
  
      &lt;TextView
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_gravity="center_horizontal"
          android:autoLink="web"
          android:textStyle="bold" /&gt;
  
      &lt;ScrollView
          android:id="@+id/groupScrollView"
          android:layout_width="match_parent"
          android:layout_height="match_parent" &gt;
  
          &lt;LinearLayout
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:orientation="vertical" &gt;
  
              &lt;com.google.android.youtube.player.YouTubePlayerView
                  android:id="@+id/youtubeplayerview"
                  android:layout_width="match_parent"
                  android:layout_height="wrap_content" /&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView1a"
                      android:layout_width="0dip"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:text="Throw &amp;apos;Em Up"
                      android:textAppearance="?android:attr/textAppearanceMedium" /&gt;
  
                  &lt;Button
                      android:id="@+id/fav_up_btn1"
                      android:layout_width="27dp"
                      android:layout_height="27dp"
                      android:layout_alignParentTop="true"
                      android:layout_toRightOf="@+id/textView1a"
                      android:background="@drawable/fav_up_btn1"
                      android:gravity="right"
                      android:paddingRight="5dp"
                      android:paddingTop="5dp" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView2a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_toLeftOf="@+id/textView3a"
                      android:gravity="left"
                      android:text="by DJ Generic  |"
                      android:textAppearance="?android:attr/textAppearanceSmall"
                      android:textColor="@color/lightgrey" /&gt;
  
                  &lt;TextView
                      android:id="@+id/textView3a"
                      android:layout_width="0dp"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:gravity="left"
                      android:text="  100,000 views"
                      android:textAppearance="?android:attr/textAppearanceSmall" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;View
                  android:layout_width="1dp"
                  android:layout_height="25dp" &gt;
              &lt;/View&gt;
  
              &lt;com.google.android.youtube.player.YouTubeThumbnailView
                  android:id="@+id/youtubethumbnailview1"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content" /&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView1a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:text="Bulls On Parade"
                      android:textAppearance="?android:attr/textAppearanceMedium" /&gt;
  
                  &lt;Button
                      android:id="@+id/fav_up_btn"
                      android:layout_width="27dp"
                      android:layout_height="27dp"
                      android:layout_alignParentTop="true"
                      android:layout_toRightOf="@+id/textView1a"
                      android:background="@drawable/fav_up_btn1"
                      android:gravity="right"
                      android:paddingRight="5dp"
                      android:paddingTop="5dp" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView2a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_toLeftOf="@+id/textView3a"
                      android:gravity="left"
                      android:text="by Rage Against The Machine  |"
                      android:textAppearance="?android:attr/textAppearanceSmall"
                      android:textColor="@color/lightgrey" /&gt;
  
                  &lt;TextView
                      android:id="@+id/textView3a"
                      android:layout_width="0dp"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:gravity="left"
                      android:text="  100,000 views"
                      android:textAppearance="?android:attr/textAppearanceSmall" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;View
                  android:layout_width="1dp"
                  android:layout_height="25dp" &gt;
              &lt;/View&gt;
  
              &lt;com.google.android.youtube.player.YouTubeThumbnailView
                  android:id="@+id/youtubethumbnailview2"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content" /&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView1a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:text="Isaac Daniel on CNN with Anderson Cooper"
                      android:textAppearance="?android:attr/textAppearanceMedium" /&gt;
  
                  &lt;Button
                      android:id="@+id/fav_up_btn"
                      android:layout_width="27dp"
                      android:layout_height="27dp"
                      android:layout_alignParentTop="true"
                      android:layout_toRightOf="@+id/textView1a"
                      android:background="@drawable/fav_up_btn1"
                      android:gravity="right"
                      android:paddingRight="5dp"
                      android:paddingTop="5dp" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView2a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_toLeftOf="@+id/textView3a"
                      android:gravity="left"
                      android:text="by idconex  |"
                      android:textAppearance="?android:attr/textAppearanceSmall"
                      android:textColor="@color/lightgrey" /&gt;
  
                  &lt;TextView
                      android:id="@+id/textView3a"
                      android:layout_width="0dp"
                      android:layout_height="wrap_content"
                      android:layout_toRightOf="@+id/textView2a"
                      android:layout_weight="1"
                      android:gravity="left"
                      android:text="  100,000 views"
                      android:textAppearance="?android:attr/textAppearanceSmall" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;View
                  android:layout_width="1dp"
                  android:layout_height="25dp" &gt;
              &lt;/View&gt;
  
              &lt;com.google.android.youtube.player.YouTubeThumbnailView
                  android:id="@+id/youtubethumbnailview3"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content" /&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView1a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:text="Bulls On Parade"
                      android:textAppearance="?android:attr/textAppearanceMedium" /&gt;
  
                  &lt;Button
                      android:id="@+id/fav_up_btn"
                      android:layout_width="27dp"
                      android:layout_height="27dp"
                      android:layout_alignParentTop="true"
                      android:layout_toRightOf="@+id/textView1a"
                      android:background="@drawable/fav_up_btn1"
                      android:gravity="right"
                      android:paddingRight="5dp"
                      android:paddingTop="5dp" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView2a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_toLeftOf="@+id/textView3a"
                      android:gravity="left"
                      android:text="by Rage Against The Machine  |"
                      android:textAppearance="?android:attr/textAppearanceSmall"
                      android:textColor="@color/lightgrey" /&gt;
  
                  &lt;TextView
                      android:id="@+id/textView3a"
                      android:layout_width="0dp"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:gravity="left"
                      android:text="  100,000 views"
                      android:textAppearance="?android:attr/textAppearanceSmall" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;View
                  android:layout_width="1dp"
                  android:layout_height="25dp" &gt;
              &lt;/View&gt;
  
              &lt;com.google.android.youtube.player.YouTubeThumbnailView
                  android:id="@+id/youtubethumbnailview4"
                  android:layout_width="wrap_content"
                  android:layout_height="wrap_content" /&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;ImageButton
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_alignParentCenter="true"
                      android:layout_weight="1"
                      android:text="@drawable/selstation_up_btn" /&gt;
  
                  &lt;TextView
                      android:id="@+id/textView1a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:text="Isaac Daniel on CNN with Anderson Cooper"
                      android:textAppearance="?android:attr/textAppearanceMedium" /&gt;
  
                  &lt;Button
                      android:id="@+id/fav_up_btn"
                      android:layout_width="27dp"
                      android:layout_height="27dp"
                      android:layout_alignParentTop="true"
                      android:layout_toRightOf="@+id/textView1a"
                      android:background="@drawable/fav_up_btn1"
                      android:gravity="right"
                      android:paddingRight="5dp"
                      android:paddingTop="5dp" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;LinearLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:orientation="horizontal" &gt;
  
                  &lt;TextView
                      android:id="@+id/textView2a"
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_toLeftOf="@+id/textView3a"
                      android:gravity="left"
                      android:text="by idconex  |"
                      android:textAppearance="?android:attr/textAppearanceSmall"
                      android:textColor="@color/lightgrey" /&gt;
  
                  &lt;TextView
                      android:id="@+id/textView3a"
                      android:layout_width="0dp"
                      android:layout_height="wrap_content"
                      android:layout_weight="1"
                      android:gravity="left"
                      android:text="  100,000 views"
                      android:textAppearance="?android:attr/textAppearanceSmall" /&gt;
              &lt;/LinearLayout&gt;
  
              &lt;RelativeLayout
                  android:layout_width="fill_parent"
                  android:layout_height="wrap_content"
                  android:background="#AAFFFFFF" &gt;
  
                  &lt;ImageButton
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_alignParentLeft="true"
                      android:src="@drawable/scroll_lt_arrow" /&gt;
  
                  &lt;ImageButton
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_alignParentCenter="true"
                      android:text="@drawable/selstation_up_btn" /&gt;
  
                  &lt;ImageButton
                      android:layout_width="wrap_content"
                      android:layout_height="wrap_content"
                      android:layout_alignParentRight="true"
                      android:src="@drawable/scroll_rt_arrow" /&gt;
              &lt;/RelativeLayout&gt;
  
              &lt;View
                  android:layout_width="1dp"
                  android:layout_height="5dp" &gt;
              &lt;/View&gt;
          &lt;/LinearLayout&gt;
      &lt;/ScrollView&gt;
  
  &lt;/android.support.v4.widget.DrawerLayout&gt;
  </code></pre>