title: Select all checkbox in dojo 1.4 grid
body: <p>while migrating from dojo 1.02 to 1.4 i have encountered a problem with grid. </p>
  
  <p>In 1.02 versions i have implemented my own check box class inherriting from dojox.grid._CheckBoxSelector</p>
  
  <pre><code>dojo.provide("MyCheckBox");
  dojo.declare("MyCheckBox", dojox.grid._CheckBoxSelector, {
  
    format: function(inDatum, inRowIndex)
    {
      return '&lt;input class="dojoxGrid-input dojoxGrid-checkbox" type="checkbox"' + 
      (inDatum ? ' checked="checked"' : '') + ' style="width: auto" /&gt;' }
    }
  }
  </code></pre>
  
  <p>in layout i pointed editor to this classs</p>
  
  <pre><code>editor:MyCheckBox
  </code></pre>
  
  <p>and that's about it.</p>
  
  <p>In 1.4 there is no _CheckBoxSelector and i should use enhanced grid with indirectSelection, but there is no option for check all acheckbox in header !!</p>
  
  <p>The only way i know to overcome it is by setting format functions and build a checkbox in it, 
  but i want it to be coupled in grid object.</p>
  
  <p>Thanks in advance</p>