我已经bluez使用命令清除了
sudo apt-get --purge remove bluez
但unity-control-center也被卸载了。
我无法再重新安装它，它显示此错误消息：
$ sudo apt-get install unity-control-center
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
unity-control-center : Depends: indicator-bluetooth but it is not installable
E: Unable to correct problems, you have held broken packages.
我的系统是 Ubuntu 14.04。
我该如何修复此问题并恢复 Unity 控制中心？