title: Uncaught TypeError: this.function is not a function
body: <p>Hi this is my (shortcuted) example code:</p>
  
  <pre><code>export class SolarSystemInfo {
  
      constructor() {
          this.test();
      }
  
      // click on solar system
      clickSolarSystem() {
          $("body").on("click",".hex", function() {
              this.test();
          }); 
      }
  
      public test () {
          alert('test');
      }
  
  }
  </code></pre>
  
  <p>My problem is, that in constructor is <strong>test</strong> function called right, but in <strong>clickSolarSystem</strong> function after calling <em>this.test()</em> I get: <strong><em>Uncaught TypeError: this.test is not a function</em></strong><br>
  How I have to call <strong>test</strong> function in my function inner class?<br>
  Thanks</p>