title: Inheritance and ObservableCollection
body: <p>I'm developing a Windows Phone 8 application.</p>
  
  <p>I have this class:</p>
  
  <pre><code>public class LocationToShow : ARItem
  </code></pre>
  
  <p>And, these two collections:</p>
  
  <pre><code>ObservableCollection&lt;ARItem&gt; arItems;
  ObservableCollection&lt;LocationToShow&gt; locations;
  </code></pre>
  
  <p>When I do this:</p>
  
  <pre><code>arItems = locations;
  </code></pre>
  
  <p>I get the following error:</p>
  
  <pre><code>Can't convert implicity the type ObservableCollection&lt;LocationToShow&gt; into the type ObservableCollection&lt;ARItem&gt;
  </code></pre>
  
  <p>But if I do this:</p>
  
  <pre><code>arItems = (ObservableCollection&lt;ARItem&gt;)locations;
  </code></pre>
  
  <p>I get this error:</p>
  
  <pre><code>Can't convert the type ObservableCollection&lt;LocationToShow&gt; into the type ObservableCollection&lt;ARItem&gt;
  </code></pre>
  
  <p><strong>How can I fix this problem?</strong></p>