Unnecessary definition of resource in Google's Android Notepad tutorial?
<p>I am learning Android from Notepad tutorial and one thing confuses me. Since Notepad2 in file notes_list.xml is used + with definition of id resource:</p>

<pre><code>&lt;ListView android:id="@+id/android:list"
&lt;TextView android:id="@+id/android:empty"
</code></pre>

<p>But from what I have read + sign is nnecessary  only when defining new resource and list and empty is not new, but it is provided by android. So why did they used + sign then? If you delete program runs anyway.</p>
