code: public void layoutChildren() {
  
          Set<Integer> copySet;
          synchronized (mMeasuredChildren) {
              Log.d(Log.SUBSYSTEM.LAYOUT, TAG, "layoutChildren [%d] layout = %s",
                      mMeasuredChildren.size(), this);
              copySet = new HashSet<>(mMeasuredChildren);
          }
          for (int nextMeasured: copySet) {
              Widget child = mContainer.get(nextMeasured);
              if (child != null) {
                  child.preventTransformChanged(true);
                  layoutChild(nextMeasured);
                  postLayoutChild(nextMeasured);
                  child.preventTransformChanged(false);
              }
  
          }
      }
docs: Layout children inside the layout container