ubuntu下面板上無網絡連接的圖標

解決方法：刪除舊的網絡配置，重新讓networkManager自動配置

sudo service network-manager stop
sudo rm /var/lib/NetworkManager/NetworkManager.state
sudo service network-manager start
 
sudo gedit /etc/NetworkManager/nm-system-settings.conf
false----改成--->true
 
sudo service network-manager restart