title: android app crashing on startActivity()
body: <p>I have started an Intent and asked it to go to the main activity, when it attempts it the app crashes.</p>
  
  <p>Here is the code that tries to go to the main activity.</p>
  
  <pre><code>Intent i = new Intent(
  ".MAIN_ACTIVITY");
  startActivity(i);   
  </code></pre>
  
  <p>Here is the XML manifest for Main_Activity.</p>
  
  <pre><code>&lt;activity
      android:name=".MainActivity"
      android:label="@string/app_name" &gt;
      &lt;intent-filter&gt;
          &lt;action android:name="android.intent.action.MAIN_ACTIVITY" /&gt;
  
          &lt;category android:name="android.intent.category.DEFAULT" /&gt;
      &lt;/intent-filter&gt;
  &lt;/activity&gt;
  </code></pre>
  
  <p>I'm still pretty new to this so any help and/or advice is of great value.</p>