title: Flutter: Trying to bottom-center an item in a Column, but it keeps left-aligning
body: <p>I'm trying to bottom-center a widget at the bottom of a Column, but it keeps aligning to the left.</p>
  
  <pre><code>return new Column(
    new Stack(
      new Positioned(
        bottom: 0.0, 
        new Center(
          new Container(),
        ),
      ),
    ),
  ); 
  </code></pre>
  
  <p>The existence of the Positioned forces the Container to the left, instead of centering. Removing the Positioned, however, puts the Container in the middle-center.</p>