code: private void handleRelease() {
          float speed = Math.max(dragHelper.getDragSpeed(), animationSpeed);
  
          if (getTopMargin() > initialMargin ||
                  (dragHelper.getDragSpeed() > animationSpeed && dragHelper.getDragDistance() > 0) ||
                  (getDeviceType(getContext()) == DeviceType.TABLET && isMaximized() &&
                          getTopMargin() > minMargin)) {
              animateHideView(parentHeight - getTopMargin(), speed, new DecelerateInterpolator(),
                      true);
          } else {
              animateShowView(-(getTopMargin() - minMargin), speed, new DecelerateInterpolator());
          }
      }
docs: Handles when a drag gesture has been ended by the user.