def insertDomain(self, domain, indegree=0, outdegree=0):
		'''增加一个域名'''
		cur = self.conn.cursor()
		cur.execute("INSERT INTO Domains VALUES (NULL,?,?,?)", (domain, indegree, outdegree))
		# 写入到文件中
		self.conn.commit()
def _init_gui(self):
    self._size_spin_button = gtk.SpinButton(
      gtk.Adjustment(
        value=0,
        lower=self._min_size,
        upper=self._max_size,
        step_incr=1,
        page_incr=10,
      ),
      digits=0)