[...]
   activate: (state) ->
     @helloWorldView = new HelloWorldView (state.helloWorldViewState)
     @modalPanel = atom.workspace.addModalPanel(item: @helloWorldView.getElement(), visible: false)

     # Atom-Events lassen sich über CompositeDisposable einfach aufräumen
     @subscriptions = new CompositeDisposable

     # @toggle()-Methode mit 'hello-world:toggle' verknüpfen
     @subscriptions.add atom.commands.add 'atom-workspace', 'hello-world:toggle': => @toggle()

   deactivate: ->
     @modalPanel.destroy()
     @subscriptions.dispose()
     @helloWorldView.destroy()

   serialize: ->
     helloWorldViewState: @helloWorldView.serialize()

   toggle: ->
     console.log 'HelloWorld was toggled!'

     if @modalPanel.isVisible()
       @modalPanel.hide()
     else
       @modalPanel.show()