+ assert(owner_ || owner);
+ v_offset_animation_.stop();
+
+ if (owner_) {
+ const int owner_offset = owner_->owner_visual_v_offset();
+ layout_v_offset_ += owner_offset;
+ visual_v_offset_ += owner_offset;
+ }
+
+ owner_ = owner;
+
+ if (owner_) {
+ const int owner_offset = owner_->owner_visual_v_offset();
+ layout_v_offset_ -= owner_offset;
+ visual_v_offset_ -= owner_offset;
+ }