title: dojo charting - problem with onmousemove over chart plotArea
body: <p>I'm trying to build a chart which draws a vertical line to the X axis under the cursor. Using this as a guideline:</p>
  
  <p><a href="http://dojo-toolkit.33424.n3.nabble.com/Charting-events-td40659.html" rel="nofollow noreferrer">http://dojo-toolkit.33424.n3.nabble.com/Charting-events-td40659.html</a></p>
  
  <p>I am using the following code to catch 'mouseout' &amp; 'mousemove' for 
  the chart plot area (excludes the chart margins and labels)</p>
  
  <pre><code>        chart = new dojox.charting.Chart2D("rating");
          chart.addPlot("default", {
              type: "Bubble"
          });
  
          chart.addPlot("grid", {
              type: "Grid",
              hMinorLines: true
          });
  
          var plotArea = chart.surface.rawNode.children[1];
          dojo.connect(plotArea, "onmousemove", this, this.showRatingHighlight);
          dojo.connect(plotArea, "onmouseout", this, this.hideRatingHighlight);
  </code></pre>
  
  <p>Generally, it works as expected. however I also have a grid drawn on the chart, and whenever the mouse passes over the grid lines, I get a "mouseout" event. I also lose the mousemove event when the mouse passes over a marker with a toolTip/highlight action in place.</p>
  
  <p>Q: How can I catch mousemove/mousemove over the 'plotArea' without losing it over the gridlines or plot Markers?</p>
  
  <p>Q: Is there a better way to get the 'plotArea' of the chart for calculating offsets?</p>