void addFill(int row,int col){
  RowView rv=getRow(row);
  if (rv != null) {
    rv.fillColumn(col);
  }
}

void addFill ( int row , int col ) { RowView rv = getRow ( row ) ; if ( rv != null ) { rv . fillColumn ( col ) ; } }
mark a grid location as filled in for a cells overflow .
