column index

How do I get the column index when I click the couse in a cell?

obj.setAction('click', function(src){
row = src.getRowProperty('index');
col = src.getColumnProperty('index');
try{
myOnClick(row,col);
}
catch(error){}
});

myOnClick is a function which can do anything with the coordinates
this must be wrote in the html page as a <script> function