title: How to add view to cardview inside livedata observer
body: <p>I am trying to add some radio button into a card view. Here's my code:</p>
  
  <p><strong>MainActivity.java</strong></p>
  
  <pre><code>cardView = findViewById(R.id.card_view);
  mGameViewModel.setUpGame().observe(this,this::loadRound);
  
  private void loadRound(List&lt;Smiley&gt; smileys) {
      if (smileys == null) {
          return;
      }
      mAnswersView.loadAnswers(smileys, cardView);
      mGameViewModel.startNewGameRound();
  }
  </code></pre>
  
  <p><strong>AnswerView</strong></p>
  
  <pre><code>public void loadAnswers(List&lt;Smiley&gt; smileys, CardView cardView) {
      if (smileys == null) {
          return;
      }
      removeAllViews();
      LayoutInflater inflater = LayoutInflater.from(getContext());
  
      for (Smiley smiley : smileys) {
          RadioButton button = (RadioButton) inflater.inflate(R.layout.answer_item, this, false);
          button.setText(smiley.getName());
          button.setTag(R.string.answer_tag, smiley.getCode());
          cardView.addView(button);
      }
  }
  </code></pre>
  
  <p>But that doesn't seem to work. Any idea please?</p>
  
  <p>EDIT:
  The problem here is that the radio button i try to create doesn't show. I've already do some debugging and all of the methods are called until the addView method. But when i take a look on the device, there's no 'extended' view, in this case, radio button at all.</p>