title: Android Studio XML does not recognize objectAnimator
body: <p>I have been trying to animate a transition between two fragments.  I had originally placed them a property animations in xml (and that didn't really work), then changed it to objectAnimator.  For some reason Android Studio is not recognizing the objectAnimator tag. </p>
  
  <p>here is my AndroidManifest.xml:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.example.nick.randomapplication" &gt;
  
      &lt;application
          android:allowBackup="true"
          android:icon="@drawable/ic_launcher"
          android:label="@string/app_name"
          android:theme="@style/Theme.Base.AppCompat.Light" &gt;
          &lt;activity
              android:name=".MainActivity"
              android:label="@string/app_name" &gt;
              &lt;intent-filter&gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
                      &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
      &lt;/application&gt; 
  &lt;/manifest&gt;
  </code></pre>
  
  <p>my build.Gradle:</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 20
      buildToolsVersion "20.0.0"
  
      defaultConfig {
          applicationId "com.example.nick.randomapplication"
          minSdkVersion 19
          targetSdkVersion 20
          versionCode 1
          versionName "1.0"
      }
      buildTypes {
          release {
              runProguard false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      compile "com.android.support:appcompat-v7:20.0.+"
  }
  </code></pre>
  
  <p>and the xml file:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"&gt;
  &lt;/objectAnimator&gt;
  </code></pre>
  
  <p>Thank you for taking your time to look at this. I'm not sure what to do anymore.</p>