title: Run void method in background
body: <p>I want to run a method in background using rxjava. I don't care about the result.</p>
  
  <pre><code>void myHeavyMethod() { (...) }
  </code></pre>
  
  <p>So far the only solution I have is to modify the return type to e.g. <code>boolean</code>.</p>
  
  <pre><code>boolean myHeavyMethod() { (...) return true; }
  </code></pre>
  
  <p>Afterwards I run:</p>
  
  <pre><code>Completable.defer(() -&gt; Completable.fromCallable(this::myHeavyMethod))
          .subscribeOn(Schedulers.computation())
          .subscribe(
                  () -&gt; {},
                  throwable -&gt; Log.e(TAG, throwable.getMessage(), throwable)
          );
  </code></pre>
  
  <p>Is there a way to do it keeping the <code>void</code> return type?</p>