Meine app stürzt immer ab in Android Studio

Zur Zeit arbeite ich an einem timer-app in Android Studio und es stürzt immer ab bevor ich noch ausführen. Ich muss es heute Abend getan, so kann es sein, meinem Vater, Weihnachtsgeschenk (es für seine Firma).

Hier ist mein code:

JS:

public class TimerActivity extends ActionBarActivity {
    Button btnStart = (Button) findViewById(R.id.btnStart);
    TextView txtTimer = (TextView) findViewById(R.id.textViewTime);

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_timer);
       //btnStart.setBackgroundColor(0x57C173);

        final CountDownTimer timer = new CountDownTimer(60000, 1000) {
            @Override
            public void onTick(long millisUntilFinished) {
                long secondsRemaining = millisUntilFinished / 60;
                long minutesRemaining = secondsRemaining / 60;
                secondsRemaining = secondsRemaining % 60;

                txtTimer.setText(minutesRemaining + ":" + secondsRemaining);
            }

            @Override
            public void onFinish() {
                txtTimer.setText("You are Awesome!");
            }
        };

        btnStart.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                timer.start();
                btnStart.setText("Cancel");

                btnStart.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        timer.cancel();
                        btnStart.setText("Start");
                        txtTimer.setText("1:00");
                    }
                });
            }
        });
    }
}

Und hier ist, was mein Logcat sagt:

HTML:

12-24 14:48:01.324  16878-16878/com.mintemovement.minutemovement W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x416a9e30)
12-24 14:48:01.334  16878-16878/com.mintemovement.minutemovement E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.mintemovement.minutemovement, PID: 16878
    java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.mintemovement.minutemovement/com.mintemovement.minutemovement.TimerActivity}: java.lang.NullPointerException
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2357)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2495)
            at android.app.ActivityThread.access$800(ActivityThread.java:153)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1349)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:157)
            at android.app.ActivityThread.main(ActivityThread.java:5633)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:896)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:712)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.NullPointerException
            at android.app.Activity.findViewById(Activity.java:1952)
            at com.mintemovement.minutemovement.TimerActivity.<init>(TimerActivity.java:12)
            at java.lang.Class.newInstanceImpl(Native Method)
            at java.lang.Class.newInstance(Class.java:1208)
            at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2348)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2495)
            at android.app.ActivityThread.access$800(ActivityThread.java:153)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1349)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:157)
            at android.app.ActivityThread.main(ActivityThread.java:5633)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:896)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:712)
            at dalvik.system.NativeStart.main(Native Method)