Android: switching from one layout activity to another

I am trying to display a splash screen for 3 seconds and then go to the main screen, both of them being in the same class. However, my problem is that, when I try calling the new layout.activity, before the original layout.acitity for the class Im in, the program crash. Why?

Here is a little example of what I am talkin about:

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_splash);//new activity 
    displaySplash();

    setContentView(R.layout.activity_visualizer);//original activity 

The only way that I can get this to run is if I comment out the splash activity completely, but I need it! I wont work if I comment out the other layout activity...

Here are my two activities if it helps:

<LinearLayout xmlns:android="http://ift.tt/nIICcg"
xmlns:tools="http://ift.tt/LrGmb4"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:background="#000000"
tools:context="comp380.musicvisualizer.Visualizer" >

<ListView
    android:id="@+id/song_list"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" >
</ListView>

<LinearLayout xmlns:android="http://ift.tt/nIICcg"
xmlns:tools="http://ift.tt/LrGmb4"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#000000"
tools:context="comp380.musicvisualizer.Visualizer" >

<ImageView
    android:id="@+id/splashscreen"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:src="@drawable/logo"
    android:layout_gravity="center"/>