title: calc columns in datagrid
body: <p>I really need your help. Personnel am with the following problem:
  I have a datagrid where I have a column called: Column 2, which has a fixed number and the rest is with editable columns = true so that my client can enter data.
  I wish every since I could manually inserted to call a funcion where I make a comparison. That line I'm changing the values ¿¿inserted into the line can not be greater than the value of the column: Column 2</p>
  
  <p>and this was done for each sample line</p>
  
  <pre><code> Line 1: Fixed number ==&gt; 85
   I can get editable columns in column 3: value = 20
   I can get editable columns in column 4: value = 50
   I can get editable columns in column 5: value = 100
  </code></pre>
  
  <p>when the value is greater than the column Column 2 emits an alert.</p>
  
  <p>I'm using Flex 3</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"&gt;
  &lt;mx:ArrayCollection id="arrColl"&gt;
      &lt;mx:source&gt;
          &lt;mx:Array&gt;
              &lt;mx:Object label="Student A" score="85" /&gt;
              &lt;mx:Object label="Student B" score="48" /&gt;
              &lt;mx:Object label="Student C" score="71" /&gt;
              &lt;mx:Object label="Student D" score="88" /&gt;
              &lt;mx:Object label="Student E" score="24" /&gt;
              &lt;mx:Object label="Student F" score="64" /&gt;
              &lt;mx:Object label="Student G" score="76" /&gt;
              &lt;mx:Object label="Student H" score="76" /&gt;
              &lt;mx:Object label="Student I" score="93" /&gt;
              &lt;mx:Object label="Student J" score="88" /&gt;
              &lt;mx:Object label="Student K" score="48" /&gt;
              &lt;mx:Object label="Student L" score="76" /&gt;
          &lt;/mx:Array&gt;
      &lt;/mx:source&gt;
  &lt;/mx:ArrayCollection&gt;
  &lt;mx:DataGrid x="396" y="309" dataProvider="{arrColl}" editable="true"&gt;
      &lt;mx:columns&gt;
          &lt;mx:DataGridColumn headerText="Column 1"  dataField="label"  /&gt;
          &lt;mx:DataGridColumn headerText="Column 2"  dataField="score"  /&gt;
          &lt;mx:DataGridColumn headerText="Column 3"  editable="true"  dataField="col1"/&gt;
          &lt;mx:DataGridColumn headerText="Column 4"  editable="true"  dataField="col2"/&gt;
          &lt;mx:DataGridColumn headerText="Column 5"  editable="true"  dataField="col3"/&gt;
          &lt;mx:DataGridColumn headerText="Column 6"  editable="true"  dataField="col4"/&gt;
          &lt;mx:DataGridColumn headerText="Column 7"  editable="true"  dataField="col5" /&gt;
      &lt;/mx:columns&gt;
  &lt;/mx:DataGrid&gt;
  </code></pre>
  
  <p></p>