how to disconnect a signal handler in windowManager except using disconnect

[zhh zhou <zhouzhh217 gmail com>]

Hello, I want to write a gnome-shell extension to add some eye candy effects while minimizing, maximizing and closing a window for current window manager. So I have to disconnect the default signal handler, such as minimize signal handler. However, the wm object only has disconnect function which needs a signal handler ID as parameter and the ID is not saved in windowManager.js. So if I want to disconnect it, I have to modify the windowManager.js like this:

  

   this._minHandlerID = this._shellwm.connect('minimize', Lang.bind(this, this._minimizeWindow));

Can anyone have a idea that does not need to modify windowManager.js ? Thanks very much~