code: @Override
      protected BaseDialogFragment.Builder build(BaseDialogFragment.Builder builder) {
          final CharSequence title = getTitle();
          if (!TextUtils.isEmpty(title)) {
              builder.setTitle(title);
          }
  
          final CharSequence message = getMessage();
          if (!TextUtils.isEmpty(message)) {
              builder.setMessage(message);
          }
  
          final CharSequence positiveButtonText = getPositiveButtonText();
          if (!TextUtils.isEmpty(positiveButtonText)) {
              builder.setPositiveButton(positiveButtonText, new View.OnClickListener() {
                  @Override
                  public void onClick(View view) {
                      for (IPositiveButtonDialogListener listener : getPositiveButtonDialogListeners()) {
                          listener.onPositiveButtonClicked(mRequestCode);
                      }
                      dismiss();
                  }
              });
          }
  
          final CharSequence negativeButtonText = getNegativeButtonText();
          if (!TextUtils.isEmpty(negativeButtonText)) {
              builder.setNegativeButton(negativeButtonText, new View.OnClickListener() {
                  @Override
                  public void onClick(View view) {
                      for (INegativeButtonDialogListener listener : getNegativeButtonDialogListeners()) {
                          listener.onNegativeButtonClicked(mRequestCode);
                      }
                      dismiss();
                  }
              });
          }
  
          final CharSequence neutralButtonText = getNeutralButtonText();
          if (!TextUtils.isEmpty(neutralButtonText)) {
              builder.setNeutralButton(neutralButtonText, new View.OnClickListener() {
                  @Override
                  public void onClick(View view) {
                      for (INeutralButtonDialogListener listener : getNeutralButtonDialogListeners()) {
                          listener.onNeutralButtonClicked(mRequestCode);
                      }
                      dismiss();
                  }
              });
          }
  
          return builder;
      }
docs: Key method for extending {@link com.avast.android.dialogs.fragment.SimpleDialogFragment}.
  Children can extend this to add more things to base builder.