Android Studio - Como crear un patron de desbloqueo

Librerias: https://github.com/aritraroy/PatternLockView
                 https://github.com/pilgr/Paper


activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/colorPrimaryDark"

    tools:context="com.example.usuario.lockpattern.MainActivity">

    <com.andrognito.patternlockview.PatternLockView
        android:id="@+id/pattern_lock_view"
        android:layout_width="280dp"
        android:layout_height="280dp"
        android:layout_centerInParent="true"/>


   <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Guardar Patron"
    android:id="@+id/btnSetearPatron"
       android:layout_below="@+id/pattern_lock_view"
       android:layout_centerHorizontal="true"/>


</RelativeLayout>

activity_principal.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_principal"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/colorPrimaryDark"
    tools:context="com.example.usuario.lockpattern.Principal">


    <com.andrognito.patternlockview.PatternLockView
        android:id="@+id/pattern_lock_view"
        android:layout_width="280dp"
        android:layout_height="280dp"
        android:layout_gravity="center"
        android:layout_centerInParent="true"/>

</RelativeLayout>

MainActivity.java

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import com.andrognito.patternlockview.PatternLockView;
import com.andrognito.patternlockview.listener.PatternLockViewListener;
import com.andrognito.patternlockview.utils.PatternLockUtils;

import java.util.List;

import io.paperdb.Paper;


public class MainActivity extends AppCompatActivity {

    String save_pattern_key = "pattern_code";
    String final_pattern = "";
    PatternLockView mPatternLockView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Paper.init(this);
        final String save_pattern = Paper.book().read(save_pattern_key);
        if(save_pattern != null && !save_pattern.equals("null"))
        {
            setContentView(R.layout.activity_principal);
            mPatternLockView = (PatternLockView)findViewById(R.id.pattern_lock_view);
            mPatternLockView.addPatternLockListener(new PatternLockViewListener() {
                @Override
                public void onStarted() {

                }

                @Override
                public void onProgress(List<PatternLockView.Dot> progressPattern) {

                }

                @Override
                public void onComplete(List<PatternLockView.Dot> pattern) {
                    final_pattern = PatternLockUtils.patternToString(mPatternLockView,pattern);
                    if(final_pattern.equals(save_pattern)){
                        Toast.makeText(MainActivity.this, "Password Correct!", Toast.LENGTH_SHORT).show();
                        Intent intent = new Intent(MainActivity.this,ActividadDesbloqueada.class);
                        startActivity(intent);


                    }else{ Toast.makeText(MainActivity.this, "Password Incorrecta!", Toast.LENGTH_SHORT).show();}


                }

                @Override
                public void onCleared() {

                }
            });
        }
        else
        {

            setContentView(R.layout.activity_main);
            mPatternLockView = (PatternLockView)findViewById(R.id.pattern_lock_view);
            mPatternLockView.addPatternLockListener(new PatternLockViewListener() {
                @Override
                public void onStarted() {

                }

                @Override
                public void onProgress(List<PatternLockView.Dot> progressPattern) {

                }

                @Override
                public void onComplete(List<PatternLockView.Dot> pattern) {
                    final_pattern = PatternLockUtils .patternToString(mPatternLockView,pattern);

                }

                @Override
                public void onCleared() {

                }
            });




            Button btnSetup = (Button)findViewById(R.id.btnSetearPatron);
            btnSetup.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    Paper.book().write(save_pattern_key, final_pattern);
                    Toast.makeText(MainActivity.this, "Save pattern okay!", Toast.LENGTH_SHORT).show();
                    Intent intent = new Intent(MainActivity.this,Principal.class);
                    startActivity(intent);
                }
            });
        }
    }
}

Principal.java

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Toast;

import com.andrognito.patternlockview.PatternLockView;
import com.andrognito.patternlockview.listener.PatternLockViewListener;
import com.andrognito.patternlockview.utils.PatternLockUtils;

import java.util.List;

import io.paperdb.Paper;

public class Principal extends AppCompatActivity {


    String save_pattern_key = "pattern_code";
    PatternLockView mPatternLockView;
    String final_pattern = "";



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Paper.init(this);
        final String save_pattern = Paper.book().read(save_pattern_key);
        if(save_pattern != null && !save_pattern.equals("null"))
        {
            setContentView(R.layout.activity_principal);
            mPatternLockView = (PatternLockView)findViewById(R.id.pattern_lock_view);
            mPatternLockView.addPatternLockListener(new PatternLockViewListener() {
                @Override
                public void onStarted() {

                }

                @Override
                public void onProgress(List<PatternLockView.Dot> progressPattern) {

                }

                @Override
                public void onComplete(List<PatternLockView.Dot> pattern) {
                    final_pattern = PatternLockUtils.patternToString(mPatternLockView,pattern);
                    if(final_pattern.equals(save_pattern)){
                        Toast.makeText(Principal.this, "Password Correct!", Toast.LENGTH_SHORT).show();
                        Intent intent = new Intent(Principal.this,ActividadDesbloqueada.class);
                        startActivity(intent);


                    }else{ Toast.makeText(Principal.this, "Password Incorrecta!", Toast.LENGTH_SHORT).show();}


                }

                @Override
                public void onCleared() {

                }
            });
        }
    }
}