more my task classes

MainActivity.java
============================

import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{
    Context context;
    EditText lUser,lPass;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setPointer();
    }

    private void setPointer() {
        lUser=(EditText)findViewById(R.id.userLogin);
        lPass=(EditText)findViewById(R.id.userPass);
        this.context=this;
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()){
            case R.id.btnLogin:
                /*//                         Key                       Value
                if (!SharedPref.checkPass(lUser.getText().toString(),lPass.getText().toString(),this))
                {
                    Toast.makeText(this, "Invalid user name or pass", Toast.LENGTH_LONG).show();
                    return;
                }
                */

                //check if user exists
                if (!SharedPref.checkUserExists(lUser.getText().toString(),context))
                {
                    AlertDialog.Builder dlgNewUser = new AlertDialog.Builder(context);
                    //dlgNewUser.setTitle("user does not exists");
                    //dlgNewUser.setMessage("do you wish to create new user");
                    //dlgNewUser.setView()   -> for inflater
                    View myDlgView = LayoutInflater.from(context).inflate(R.layout.dialog_layout,null);
                    dlgNewUser.setView(myDlgView);
                    dlgNewUser.setPositiveButton("Create", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {
                            startActivity(new Intent(context,Register.class));
                            dialogInterface.dismiss();
                        }
                    });
                    dlgNewUser.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {
                            dialogInterface.dismiss();
                        }
                    });
                    dlgNewUser.show();
                }
                else {
                    Intent intent = new Intent(this, Tasks.class);
                    //intent.putExtra("userName",lUser.getText().toString());
                    intent.putExtra("userName", "zeev");
                    startActivity(intent);
                }
                break;

            case R.id.btnRegister:
                startActivity(new Intent(this,Register.class));
                break;

            default:
                Toast.makeText(this, "Error in button", Toast.LENGTH_SHORT).show();
        }
    }

    private void checkLogin() {
    }
}


dialog_layout.xml
=======================
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#000000">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="User not exists !!!"
        android:textColor="#ff0000"
        android:textSize="22sp"
        android:layout_marginBottom="20dp"
        android:layout_gravity="center" />
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="User not found in the system"
        android:textColor="#ffffff"
        android:textSize="22sp"
        android:layout_marginBottom="5dp"/>
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="do you wish to create a new one"
        android:textColor="#ffffff"
        android:textSize="22sp"/>
</LinearLayout>