How to use

getAnchorId

method

in

android.support.design.widget.CoordinatorLayout$LayoutParams

@Override
protected HashMap<String, Object> fillValues(ViewGroup.LayoutParams lp, HashMap<String, Object> data, HashMap<String, Object> parentData) {
  super.fillValues(lp, data, parentData);
  if (lp instanceof AppBarLayout.LayoutParams) {
    AppBarLayout.LayoutParams alp = (AppBarLayout.LayoutParams) lp;
    data.put("LayoutParams_ScrollFlags", getTranslator().appBarLayoutScrollFlags(alp.getScrollFlags()));
    data.put("LayoutParams_ScrollInterpolator", alp.getScrollInterpolator() != null ? alp.getScrollInterpolator().getClass().getName() : "null");
  }
  if (lp instanceof CollapsingToolbarLayout.LayoutParams) {
    CollapsingToolbarLayout.LayoutParams clp = (CollapsingToolbarLayout.LayoutParams) lp;
    data.put("LayoutParams_CollapseMode", getTranslator().collapseMode(clp.getCollapseMode()));
    data.put("LayoutParams_ParallaxMultiplier", clp.getParallaxMultiplier());
  }
  if (lp instanceof CoordinatorLayout.LayoutParams) {
    CoordinatorLayout.LayoutParams clp = (CoordinatorLayout.LayoutParams) lp;
    data.put("LayoutParams_AnchorId", IdsHelper.getNameForId(clp.getAnchorId()));
    data.put("LayoutParams_Behavior", clp.getBehavior() != null ? clp.getBehavior().getClass().getName() : "null");
  }
  return data;
}

final CoordinatorLayout.LayoutParams lp =
    (CoordinatorLayout.LayoutParams) child.getLayoutParams();
if (lp.getAnchorId() != appBarLayout.getId()) {

final CoordinatorLayout.LayoutParams lp =
    (CoordinatorLayout.LayoutParams) child.getLayoutParams();
if (lp.getAnchorId() != appBarLayout.getId()) {

private boolean updateFabVisibility(CoordinatorLayout parent,
                  AppBarLayout appBarLayout, FabSpeedDial child) {
  final CoordinatorLayout.LayoutParams lp =
      (CoordinatorLayout.LayoutParams) child.getLayoutParams();
  if (lp.getAnchorId() != appBarLayout.getId()) {
    // The anchor ID doesn't match the dependency, so we won't automatically
    // show/hide the FAB
    return false;
  }
  if (child.getUserSetVisibility() != VISIBLE) {
    // The view isn't set to be visible so skip changing its visibility
    return false;
  }
  if (mTmpRect == null) {
    mTmpRect = new Rect();
  }
  // First, let's get the visible rect of the dependency
  final Rect rect = mTmpRect;
  ViewGroupUtils.getDescendantRect(parent, appBarLayout, rect);
  if (rect.bottom <= appBarLayout.getMinimumHeightForVisibleOverlappingContent()) {
    // If the anchor's bottom is below the seam, we'll animate our FAB out
    child.hide();
  } else {
    // Else, we'll animate our FAB back in
    child.show();
  }
  return true;
}