Android : launch hidden app when secret code is dialed

my requirement is to launch an hidden app when a secret code is dailed.

MainActivity.java

public class MainActivity extends
        BroadcastReceiver {

    String dialed_number;

    @Override
    public void onReceive(Context context, Intent intent)
    {
        dialed_number = intent.getStringExtra(Intent.EXTRA_PHONE_NUMBER);

        if(dialed_number.equals("*0*1235#"))
        {
            Intent appIntent = new Intent(context, MainActivity.class);
            appIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            context.startActivity(appIntent);
            setResultData(null);
        }
    }

}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.tuto.bala.helloworld" >
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >

        <receiver
            android:name=".MainActivity">
        </receiver>
    </application>

</manifest>

When i run the project I get the following exception: connection problem invalid mmi code android

Can anyone please help

Regards, Bala