NullPointer Exception bei Starte, wieso? Kein setcontentView?

1/** Called when the activity is first created. */
2 @Override
3 public void onCreate(Bundle savedInstanceState) {
4 super.onCreate(savedInstanceState);
5 setContentView(R.layout.main);
6
7 new AbrufenLigen().abruf(this, true);
8 new MeineTippsErgebnis().abrufErgebnis(this, true);
9 a=this;
10 MadvertiseView madView = (MadvertiseView) findViewById(R.id.madad);
11 if(madView!=null){
12 madView.setMadvertiseViewCallbackListener(this);
13 }
14 titel[0] = (String) this.getText(R.string.prediction);
15 titel[1] = (String) this.getText(R.string.result);
16 titel[2] = (String) this.getText(R.string.meine_tipps);
17 titel[3] = (String) this.getText(R.string.info);
18
19 getSupportActionBar().hide();
20 List<Fragment> fragments = getFragments();
21 mAdapter = new PageAdapter(getSupportFragmentManager(), fragments);
22
23 mPager = (ViewPager) findViewById(R.id.pager);
24 mIndicator = (TabPageIndicator) findViewById(R.id.indicator);
25 mPager.setOffscreenPageLimit(4);
26 mAdapter.set_titles(titel);
27 mPager.setAdapter(mAdapter);
28 mIndicator.setViewPager(mPager);

1java.lang.RuntimeException: Unable to start activity ComponentInfo{de.sportwettenblogger.de.vorhersage/de.sportwettenblogger.de.vorhersage.TabWidget}: java.lang.NullPointerException
2at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2110)
3at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2135)
4at android.app.ActivityThread.access$700(ActivityThread.java:140)
5at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1237)
6at android.os.Handler.dispatchMessage(Handler.java:99)
7at android.os.Looper.loop(Looper.java:137)
8at android.app.ActivityThread.main(ActivityThread.java:4921)
9at java.lang.reflect.Method.invokeNative(Native Method)
10at java.lang.reflect.Method.invoke(Method.java:511)
11at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
12at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
13at dalvik.system.NativeStart.main(Native Method)
14Caused by: java.lang.NullPointerException
15at de.sportwettenblogger.de.vorhersage.TabWidget.onCreate(TabWidget.java:74)
16at android.app.Activity.performCreate(Activity.java:5188)
17at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
18at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2074)
19... 11 more

1if(madView!=null){
2madView.setMadvertiseViewCallbackListener(this);
3}