title: How to fix: "You need to use a Theme.AppCompat theme (or descendant) with this activity"
body: <p>I am having trouble running my Android app in a fullscreen mode per instructions of a video. When it tries to run, the app crashes with the error.</p>
  
  <p><code>"You need to use a Theme.AppCompat theme (or descendant) with this activity</code></p>
  
  <p>Manifest File</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.djsg38.hikerswatch"&gt;
  
  &lt;uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /&gt;
  &lt;uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /&gt;
  &lt;uses-permission android:name="android.permission.INTERNET" /&gt;
  
  &lt;application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:supportsRtl="true"
      android:theme="@style/AppTheme"&gt;
      &lt;activity android:name=".MainActivity"
          android:theme="@android:style/Theme.NoTitleBar.Fullscreen" &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>Styles File</p>
  
  <pre><code>&lt;resources&gt;
  
  &lt;!-- Base application theme. --&gt;
  &lt;style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"&gt;
      &lt;!-- Customize your theme here. --&gt;
      &lt;item name="colorPrimary"&gt;@color/colorPrimary&lt;/item&gt;
      &lt;item name="colorPrimaryDark"&gt;@color/colorPrimaryDark&lt;/item&gt;
      &lt;item name="colorAccent"&gt;@color/colorAccent&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>
  
  <p></p>
  
  <p>Partial MainActivity that may be useful</p>
  
  <pre><code>public class MainActivity extends AppCompatActivity {
  </code></pre>