接听电话后停止工作应用程序

Question

我写了一个应用程序并且工作正常，但在接听来电之后我的应用程序崩溃并且我得到空指针异常，我的应用程序是smsManager并且根本不使用呼叫统计，我在谷歌搜索但注意到发现， 请帮忙。 和我的代码：

public class Home extends Activity implements OnClickListener {
private ViewFlipper mFlipper;
String contactId;
int i = 0;
public static boolean clickAuto = false , groupauto = false;
public static Button SendMessage , group;

ProgressDialog dialog ;
//private static final String[] PHOTO_BITMAP_PROJECTION = new String[] { ContactsContract.CommonDataKinds.Photo.PHOTO };

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);

    setContentView(R.layout.home);

    SendMessage = (Button) findViewById(R.id.SendMessage);
    final Button SendBox = (Button) findViewById(R.id.SendBox);
    Button exit = (Button) findViewById(R.id.Home_exit);
     group =(Button) findViewById(R.id.GroupButon);
    //ImageButton Site = (ImageButton) findViewById(R.id.Site);


    mFlipper = ((ViewFlipper) this.findViewById(R.id.flipper));
    mFlipper.startFlipping();
    mFlipper.setInAnimation(AnimationUtils.loadAnimation(this,
            R.anim.push_left_in));
    mFlipper.setOutAnimation(AnimationUtils.loadAnimation(this,
            R.anim.push_left_out));

    group.setOnClickListener(this);
    SendBox.setOnClickListener(this);
    SendMessage.setOnClickListener(this);
    exit.setOnClickListener(this);

}

@Override
public void onClick(View v) {

    switch (v.getId()) {
    case R.id.SendMessage:
        SmsMultiCasting.Forward = 0;
        Intent inten = new Intent(this, MainActivity.class);
        if (SmsMultiCasting.GoNext == 0 && SmsMultiCasting.contactinfo.size() > 0)
        {
            clickAuto = true;
            dialog = new ProgressDialog(this);
            dialog.setMessage("Please wait while loading...");
            dialog.setIndeterminate(true);
            dialog.setCancelable(true);
            dialog.show();
        }
        else 
        {
            if (SmsMultiCasting.contactinfo.size() == 0 )
                Toast.makeText(Home.this, "No Contact Found Please Try Again", Toast.LENGTH_SHORT).show();
            else
            {
                try
                {
                    dialog.cancel();
                }
                catch(NullPointerException e)
                {}
                animatedStartActivity(inten);
            }
        }
        //this.finish();
        break;

    case R.id.SendBox:
        Intent intent = new Intent(this, SendFolder.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        animatedStartActivity(intent);
        break;

    case R.id.GroupButon:
        SmsMultiCasting.Forward = 0;
        if (SmsMultiCasting.GoNext == 0)
        {
            groupauto = true;
            dialog = new ProgressDialog(this);
            dialog.setMessage("Please wait while loading...");
            dialog.setIndeterminate(true);
            dialog.setCancelable(true);
            dialog.show();
        }
        else 
        {
            startActivity(new Intent(Home.this, GroupsLayout.class));
        }
        break;


    case R.id.Home_exit:
        this.finish();
    }
}

private void animatedStartActivity(final Intent intent) {
    intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
    ActivitySwitcher.animationOut(findViewById(R.id.container),
            getWindowManager(),
            new ActivitySwitcher.AnimationFinishedListener() {
                @Override
                public void onAnimationFinished() {

                    startActivity(intent);
                }
            });
}

public void createToast(String text)
        {
            Toast.makeText(getBaseContext(), text, Toast.LENGTH_SHORT).show();
        }

} 和logcat是：

    11-17 09:52:02.626: E/AndroidRuntime(6981): FATAL EXCEPTION: main
    11-17 09:52:02.626: E/AndroidRuntime(6981): java.lang.NullPointerException
    11-17 09:52:02.626: E/AndroidRuntime(6981):                                    at                                                                                      job.shayan.activity.Home.onClick(Home.java:68)
    11-17 09:52:02.626: E/AndroidRuntime(6981):                               
    at android.view.View.performClick(View.java:4171)
    11-17 09:52:02.626: E/AndroidRuntime(6981):at                            android.view.View$PerformClick.run(View.java:17186)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at android.os.Handler.handleCallback(Handler.java:615)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at android.os.Handler.dispatchMessage(Handler.java:92)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at android.os.Looper.loop(Looper.java:213)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at android.app.ActivityThread.main(ActivityThread.java:4793)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at  java.lang.reflect.Method.invokeNative(Native Method)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at  java.lang.reflect.Method.invoke(Method.java:511)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:556)
    11-17 09:52:02.626: E/AndroidRuntime(6981):     at dalvik.system.NativeStart.main(Native Method)

UPDATE /////

我弄清楚我的问题，我在应用程序类中有一个列表，并且在回答调用之后这个列表已经消失，然后如果我想使用返回零点异常，那么我重写onSaveInstanceState并且每件事都运行正常。