XML : Snackbar preventing Recyclerview from updating its view?

This is a really bizarre bug I am encountering.

If I run my code like this (adding a new item to my recyclerview), it works and updates fine:

  mListOfData.add(someNewItem);  mRecyclerViewAdapter = new RecyclerViewAdapter(this, mListOfData);  mRecyclerViewAdapter.notifyDataSetChanged();  mRecyclerView.setAdapter(mRecyclerViewAdapter);    

But if I display a Snackbar telling the user an item has been added, suddenly the list doesn't update in real time unless I recreate the activity (rotating the screen, etc):

  View view = findViewById(R.id.primary_coordinator_layout);  mListOfData.add(someNewItem);  mRecyclerViewAdapter = new RecyclerViewAdapter(this, mListOfData);  mRecyclerViewAdapter.notifyDataSetChanged();  mRecyclerView.setAdapter(mRecyclerViewAdapter);  Snackbar.make(view, "Item added!", Snackbar.LENGTH_SHORT).show();    

Any reason why this may be or how to prevent it from blocking the visual update?

Here is the XML:

  <?xml version="1.0" encoding="utf-8"?>  <LinearLayout      xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:app="http://schemas.android.com/apk/res-auto"      xmlns:tools="http://schemas.android.com/tools"      android:orientation="vertical"      android:layout_width="match_parent"      android:layout_height="match_parent">        <include          layout="@layout/toolbar_layout"          android:layout_width="match_parent"          android:layout_height="wrap_content"/>          <android.support.design.widget.CoordinatorLayout          android:id="@+id/primary_coordinator_layout"          android:orientation="vertical"          android:layout_width="match_parent"          android:layout_height="match_parent">            <LinearLayout              android:orientation="vertical"              android:layout_width="match_parent"              android:layout_height="match_parent"              android:padding="10dp">                <android.support.v7.widget.RecyclerView                  android:id="@+id/recyclerview"                  android:layout_width="match_parent"                  android:layout_height="match_parent"                  android:scrollbars="vertical" />                <TextView                  android:id="@+id/emptytext"                  android:layout_width="match_parent"                  android:layout_height="match_parent"                  android:visibility="gone"                  android:text="@string/no_items_in_recyclerview"                  android:layout_gravity="center_horizontal"                  android:gravity="center"/>          </LinearLayout>            <android.support.design.widget.FloatingActionButton              android:id="@+id/fab"              android:layout_width="wrap_content"              android:layout_height="wrap_content"              android:layout_gravity="bottom|end"              android:layout_margin="@dimen/fab_margin"              android:src="@android:drawable/ic_input_add"/>        </android.support.design.widget.CoordinatorLayout>    </LinearLayout>