Grid panel: enabling/disabling checkboxes in a grid

To change the value of the chekboxes in a grid or enabling/disabling them follow this steps:
  1. Go in your grid.
  2. Move in “Column Events” section.
  3. Create a new event: “Before Cell Click“.
  4. Hook an action like this to the event:
var currentRecord = grid.getSelectionModel().getSelected().data;
if (currentRecord.fieldToTest == 1){
 /* Don't allow edits */
 return false;
 /* Allow edits */
 return true;

Return false will prevent the natural behavior of the checkbox, making it unable to change status.