private void doWork(object state)
{
SudokuGrid sg = new SudokuGrid(path, file);
updateProgressLabel("Trabajando...");
sg.setUpPlacementOrders();
updateProgressBar();
for (int i = 0; i < 9; i++)
{
sg.doInitialPlacementFill(i);
}
updateProgressBar();
sg.populate(this);
}