var spread = 
new GC.Spread.Sheets.Workbook(document.getElementById("ss"),
{sheetCount:3});
var activeSheet = spread.getActiveSheet();
spread.commandManager().register('myCmd',
function ColorAction() 
{                   
  // Click on a cell and press the Enter key.
  activeSheet.getCell(activeSheet.getActiveRowIndex(), 
  activeSheet.getActiveColumnIndex()).backColor("red");
}
);

// Map the created action to the Enter key.
spread.commandManager().setShortcutKey('myCmd', 
GC.Spread.Commands.Key.enter, false, false, false, false);