NullPointerException in onCreate() when using findViewById - setContentView is used before?

Hello I'm writing a little Android app (Version 2.3.3). Now i get this strange NullPointer Exception in this very basic code:

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mainmenu);

newDeck = (Button) findViewById(R.id.newDeckB);
loadDeck = (Button) findViewById(R.id.loadDeckB);
viewEdition = (Button) findViewById(R.id.viewEditionB);

newDeck.setOnClickListener(this);
loadDeck.setOnClickListener(this);
viewEdition.setOnClickListener(this);
}

Im using this simple layout at the moment in main menu.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button android:id="@+id/newDeckB"
        android:text="New Deck"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>
<Button android:id="@+id/loadDeckB"
        android:text="Load Deck"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>
<Button android:id="@+id/viewEditionB"
        android:text="View Edition"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>
<TextView android:id="@+id/currentDeckTextView"
        android:text="Default Deck"
        an开发者_JAVA技巧droid:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
</LinearLayout>

Now my problem is a nullpointexception in line 25, which is the line where i set the first clickListener

newDeck.setOnClickListener(this);

Using the debugger i figured out that the button newDeck is null. I searched a lot in the web but the only answer to such kind of problem was to check that the setContentView is set before the findViewById. This is obviously the case here.

I would be very glad for any kind of advice.

Thx in Before!

Get your views and set the listeners in onPostCreate() method.

There are two events that the App expects, onCreate(), and onStart()

Which one you put this function in, matters.

I had to move "findViewByID" from onCreate() to onStart()

    @Override
protected void onStart() {
         // use findViewById() here instead of in onCreate()
    }