title: Could not identify launch Activity: Default Activity not found
body: <p>I'm new to android and I have encounterded a problem.
  The console said that "Could not identify launch activity: Default Activity not found".
  I have add </p>
  
  <pre><code>&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;
  </code></pre>
  
  <p>in manifests.
  And I have tried Invalidate caches/Restart,still not worked.
  And the class file which contains the main activity turn green in android studio. I don't know what that means.
  This is my manifests 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.example.mrrobot.mycoolweather" &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="com.example.mrrobot.mycoolweather.activity.ChooseAreaActivity"
          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>The chooseAreaActivity is the one I want to use as launcher activity.
  <a href="https://i.stack.imgur.com/QL6Aj.png"><img src="https://i.stack.imgur.com/QL6Aj.png" alt="enter image description here"></a></p>