code: public void setLabelAnimator(LabelAnimator labelAnimator) {
          if (labelAnimator == null) {
              this.labelAnimator = new DefaultLabelAnimator();
          } else {
              if (this.labelAnimator != null) {
                  labelAnimator.setLabelAnchored(getInputWidget(), getFloatingLabel(), this.labelAnimator.isAnchored());
              }
              this.labelAnimator = labelAnimator;
          }
  
          if (isInEditMode()) {
              this.labelAnimator.setLabelAnchored(getInputWidget(), getFloatingLabel(), false);
          }
      }
docs: Specifies a new LabelAnimator to handle calls to show/hide the label
  
  @param labelAnimator LabelAnimator to use; null causes use of the default LabelAnimator