title: Android ListView setAdapter issue
body: <p>I'm trying to bind data do a listview on android, but I'm not able to.</p>
  
  <p>I saw some code on the internet and it worked, but I just don't know why, and I don't want to create a new ListView on the fly, I want to use the one that is listed on the main.xml</p>
  
  <p>Why I can do this:</p>
  
  <pre><code>ListView lv = new ListView(this);
          lv.setAdapter(new ArrayAdapter&lt;String&gt;(this,android.R.layout.simple_list_item_1,PEOPLE));
          setContentView(lv);
  </code></pre>
  
  <p>But I can't do this:</p>
  
  <pre><code>ListView listPessoas = (ListView) findViewById(R.id.listPessoas);
          ArrayAdapter&lt;String&gt; adapter = new ArrayAdapter&lt;String&gt;(this, R.id.listPessoas, PESSOAS);
          listPessoas.setAdapter(adapter);
  </code></pre>