title: Label overflows window when using horizontal scrolling with chart_flutter
body: <p>I'm using charts_flutter and using a scrollable bar chart. Horizontal scrolling works great with the behaviors <code>SlidingViewport()</code> and <code>PanAndZoomBehavior()</code> (<a href="https://google.github.io/charts/flutter/example/behaviors/sliding_viewport_on_selection" rel="nofollow noreferrer">charts_flutter example</a>). I would also like to have labels follow the bar itself and stay inside the chart window when scrolling. See image.</p>
  
  <p><a href="https://i.stack.imgur.com/2Mhjr.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2Mhjr.png" alt="enter image description here"></a></p>
  
  <p>Code</p>
  
  <pre class="lang-dart prettyprint-override"><code>  BarChart(
      data,
      behaviors: [
        SlidingViewport(),
        PanAndZoomBehavior(),
      ],
      animate: true,
      domainAxis: OrdinalAxisSpec(
        viewport: OrdinalViewport('Week ${weeks.last}', 4),
      ),
    )
  </code></pre>