private void material_Click(object sender, EventArgs e)
{
whatToDo = true;
CategoryOrMaterial m = new CategoryOrMaterial(whatToDo);
m.ShowDialog();
}
private void category_Click(object sender, EventArgs e)
{
whatToDo = false;
CategoryOrMaterial c = new CategoryOrMaterial(whatToDo);
c.ShowDialog();
}