title: convert method to java 8 lambda
body: <p>How to write this method in functional programming by using Java 8 lambda / stream() in a short more intuitive way?</p>
  
  <pre><code>int animation = R.style.DialogAnimationSlideHorizontal;
  String body;
  String subject = mSubjectView.getText().toString();
  BaseDialog dialog = dialogFactory.getType(DialogTypes.DIALOG_FULL);
  
  if (!checkFields()) {
      // one of the recipients is invalid.
      body = getString(R.string.bad_address);
      dialog.showDialog(body, animation, new DialogBuilder.Positive() {
          @Override
          public void handleClick(DialogInterface dialogInterface, View view) {
              // do nothing
          }
      });
  } else if (Helpers.isEmpty(subject)) {
          // Yup, empty... send the message without a subject?
          body = getString(R.string.empty_subject_compose);
          dialog.showDialog(body, animation, new DialogBuilder.Positive() {
              @Override
              public void handleClick(DialogInterface dialogInterface, View view) {
                  // user accepted to send anyway.
                  mWebView.getComposeContent();
              }
          });
  } else {
      // everything is correct! send the message.
      mWebView.getComposeContent();
  }
  </code></pre>