title: Error inflating class RecyclerView
body: <p>So my code simply makes a list of CardViews using RecyclerView. Upon running my code i kept getting a weird error claiming there was an error in my xml. After tinkering for a while i found out that in my layout file if i change <code>&lt;RecyclerView&gt;</code> to <code>&lt;android.support.v7.widget.RecyclerView&gt;</code> everything would work just fine. Why is this happening? <br>My activity.</p>
  
  <pre><code>import android.support.v7.app.ActionBarActivity;
  import android.os.Bundle;
  import android.support.v7.widget.LinearLayoutManager;
  import android.support.v7.widget.RecyclerView;
  import android.view.Menu;
  import android.view.MenuItem;
  
  import java.util.ArrayList;
  
  
  public class CardListActivity extends ActionBarActivity {
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_card_list);
          RecyclerView recyclerView = (RecyclerView)findViewById(R.id.cardList);
          recyclerView.setHasFixedSize(true);
  
          LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
          linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
          recyclerView.setLayoutManager(linearLayoutManager);
  
          ArrayList&lt;String&gt; list = new ArrayList&lt;&gt;();
          for(int i = 0; i &lt; 20; i++) {list.add("Item " + i);}
          CardListAdapter cardListAdapter = new CardListAdapter(list);
          recyclerView.setAdapter(cardListAdapter);
      }
  
  }
  </code></pre>
  
  <p><br>My Adapter <br></p>
  
  <pre><code>    import android.support.v7.widget.RecyclerView;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.TextView;
  
  import java.util.List;
  
  public class CardListAdapter extends RecyclerView.Adapter&lt;CardListAdapter.CardListViewHolder&gt; {
  
      private List&lt;String&gt; list;
  
      public CardListAdapter(List&lt;String&gt; list) {
          this.list = list;
      }
  
      @Override
      public CardListViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
          View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.card_layout,viewGroup,false);
          return new CardListViewHolder(v);
      }
  
      @Override
      public void onBindViewHolder(CardListViewHolder cardListViewHolder, int i) {
          String s = list.get(i);
          cardListViewHolder.title.setText(s);
      }
  
      @Override
      public int getItemCount() {
          return list.size();
      }
  
  
      public static class CardListViewHolder extends RecyclerView.ViewHolder {
          TextView title;
          public CardListViewHolder(View itemView) {
              super(itemView);
              title = (TextView)itemView.findViewById(R.id.title);
          }
      }
  
  }
  </code></pre>
  
  <p><br> My layout file, note, changing <code>&lt;RecyclerView&gt;</code> to <code>&lt;android.support.v7.widget.RecyclerView&gt;</code> fixes the error. <br></p>
  
  <pre><code>&lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
  android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
  android:paddingRight="@dimen/activity_horizontal_margin"
  android:paddingTop="@dimen/activity_vertical_margin"
  android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".CardListActivity"&gt;
  
  &lt;RecyclerView
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:id="@+id/cardList"&gt;
  
      &lt;/RecyclerView&gt;
  </code></pre>
  
  <p></p>
  
  <p>When i run with <code>&lt;RecyclerView&gt;</code> i get this error, . </p>
  
  <pre><code>`Process: com.liquidink.lollipopmaterialui, PID: 7317
      java.lang.RuntimeException: Unable to start activity ComponentInfo{com.liquidink.lollipopmaterialui/com.liquidink.lollipopmaterialui.CardListActivity}: android.view.InflateException: Binary XML file line #8: Error inflating class RecyclerView
              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
              at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
              at android.app.ActivityThread.access$800(ActivityThread.java:144)
              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
              at android.os.Handler.dispatchMessage(Handler.java:102)
              at android.os.Looper.loop(Looper.java:135)
              at android.app.ActivityThread.main(ActivityThread.java:5221)
              at java.lang.reflect.Method.invoke(Native Method)
              at java.lang.reflect.Method.invoke(Method.java:372)
              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
       Caused by: android.view.InflateException: Binary XML file line #8: Error inflating class RecyclerView
              at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:757)
              at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)
              at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
              at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
              at android.view.LayoutInflater.inflate(LayoutInflater.java:365)
              at android.support.v7.app.ActionBarActivityDelegateBase.setContentView(ActionBarActivityDelegateBase.java:228)
              at android.support.v7.app.ActionBarActivity.setContentView(ActionBarActivity.java:102)
              at com.liquidink.lollipopmaterialui.CardListActivity.onCreate(CardListActivity.java:18)
              at android.app.Activity.performCreate(Activity.java:5933)
              at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
              at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
              at android.app.ActivityThread.access$800(ActivityThread.java:144)
              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
              at android.os.Handler.dispatchMessage(Handler.java:102)
              at android.os.Looper.loop(Looper.java:135)
              at android.app.ActivityThread.main(ActivityThread.java:5221)
              at java.lang.reflect.Method.invoke(Native Method)
              at java.lang.reflect.Method.invoke(Method.java:372)
              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
       Caused by: java.lang.ClassNotFoundException: Didn't find class "android.view.RecyclerView" on path: DexPathList[[zip file "/data/app/com.liquidink.lollipopmaterialui-2/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
              at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
              at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
              at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
              at android.view.LayoutInflater.createView(LayoutInflater.java:571)
              at android.view.LayoutInflater.onCreateView(LayoutInflater.java:665)
              at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:65)
              at android.view.LayoutInflater.onCreateView(LayoutInflater.java:682)
              at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:741)
              at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)
              at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
              at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
              at android.view.LayoutInflater.inflate(LayoutInflater.java:365)
              at android.support.v7.app.ActionBarActivityDelegateBase.setContentView(ActionBarActivityDelegateBase.java:228)
              at android.support.v7.app.ActionBarActivity.setContentView(ActionBarActivity.java:102)
              at com.liquidink.lollipopmaterialui.CardListActivity.onCreate(CardListActivity.java:18)
              at android.app.Activity.performCreate(Activity.java:5933)
              at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
              at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
              at android.app.ActivityThread.access$800(ActivityThread.java:144)
              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
              at android.os.Handler.dispatchMessage(Handler.java:102)
              at android.os.Looper.loop(Looper.java:135)
              at android.app.ActivityThread.main(ActivityThread.java:5221)
              at java.lang.reflect.Method.invoke(Native Method)
              at java.lang.reflect.Method.invoke(Method.java:372)
              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
      Suppressed: java.lang.ClassNotFoundException: android.view.RecyclerView
              at java.lang.Class.classForName(Native Method)
              at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
              at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
              at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
              ... 26 more
       Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available
  </code></pre>
  
  <p>`</p>