title: How to get primary or accent color of currently applied theme in angular material 2
body: <p>I'm building an app with multiple theme with angular material design 2. I created multiple theme and it's working really great.
  Using this guideline : <a href="https://material.angular.io/guide/theming" rel="noreferrer">Angular Material design theme</a></p>
  
  <p>But the problem is that if user select "green theme" for example. Then I want to display his/her name in green and so. But how can I get the currently selected theme in this case "green" in my component style and then use that primary variable in my user name class to change its color  </p>