myTasks

///////////////////////////////
        MainActivity class
//////////////////////////////

package com.example.raz.mytasks;

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    EditText txtUser;
    EditText txtPass;
    String userNameLogged;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        txtUser = (EditText)findViewById(R.id.username);
        txtPass = (EditText)findViewById(R.id.pass);
    }


    public void onClick (View v)
    {
        if (chkUser())
        {
            Intent helloIntent = new Intent(this , Hello.class);
            helloIntent.putExtra("extraUserName",txtUser.getText().toString());
            this.startActivity(helloIntent);
        }
    }

    private boolean chkUser()
    {
        SharedPreferences myPref = getApplicationContext().getSharedPreferences("myPref",MODE_PRIVATE);
        String userPass = myPref.getString(txtUser.getText().toString(), "error");
        if (userPass.equals("error") || !userPass.equals(txtPass.getText().toString()))
        {
            Toast.makeText(this, "User or password error", Toast.LENGTH_LONG).show();
            return false;
        }
        return true;
    }

    public void btnReg (View v)
    {
        Intent intentReg = new Intent(this, Register.class);
        this.startActivity(intentReg);
    }

}



/////////////////////////////
            Hello class
////////////////////////////

package com.example.raz.mytasks;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.text.InputType;
import android.view.View;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by raz on 27/03/2016.
 */
public class Hello extends Activity {
    SharedPreferences myPrefs; //calling SharedPrefrences Class
    SharedPreferences.Editor editor;//calling the editor for SharedPrefrences
    private String myText = "";
    Context context;
    TextView myTxt;
    List<utlShared> myList;
    utlShared myUtl;
    ListView myListView;

    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.hello);
        // setPoints();
        myTxt = (TextView) findViewById(R.id.hellotxt);
        myTxt.setText("Hello " + getIntent().getStringExtra("extraUserName"));
        myList = new ArrayList<>();
        myUtl = new utlShared(this,getIntent().getStringExtra("extraUserName"));
        myList = myUtl.getAllTasks();
        myListView=(ListView)findViewById(R.id.listView);
        if (myList!=null)
        {
            taskAdapter adapter = new taskAdapter(this, (ArrayList<utlShared>) myList);
            myListView.setAdapter(adapter);
        }
    }



    /*private void setPoints()
    {
        myTxt = (TextView)findViewById(R.id.hellotxt);
        myPrefs = getApplicationContext().getSharedPreferences("myPref",MODE_PRIVATE);
        editor = myPrefs.edit();
    }

    /*private String getUser()
    {
        String user = myPrefs.getString("userName","error");
        return user;
    }
*/

    public void btnAddTask(View v) {
       /* Intent AddTask = new Intent(this, AddTasks.class);
        AddTask.putExtra("userPutTask" , getIntent().getStringExtra("userName"));*/
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Input New Task");

        final EditText input = new EditText(this);
        input.setInputType(InputType.TYPE_CLASS_TEXT);
        builder.setView(input);

        builder.setPositiveButton("Add Task", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                myText = input.getText().toString();
                myUtl.newTask(myText);
                myList.add(new utlShared(myText, false));
                taskAdapter adapter = new taskAdapter(Hello.this, (ArrayList<utlShared>) myList);
                myListView.setAdapter(adapter);

            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
            }
        });
        builder.show();
    }

    public void btnExit(View v) {
        SharedPreferences myPref = getApplicationContext().getSharedPreferences("myPref", MODE_PRIVATE);
        SharedPreferences.Editor editor = myPref.edit();
        editor.remove("extraUserName");
        editor.commit();
        myTxt.setText("");
       /* Intent exit = new Intent(this,MainActivity.class);
        this.startActivity(exit);*/
        finish();
    }
}


//////////////////////////////////////
        utlShared class
//////////////////////////////////////

package com.example.raz.mytasks;

import android.content.Context;
import android.content.SharedPreferences;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * Created by raz on 27/03/2016.
 */
public class utlShared
{
    private Context context;
    private SharedPreferences userPref;
    private SharedPreferences.Editor editor;
    public String taskName;
    public Boolean taskDone;
    public String userName;
    private ArrayList<utlShared> myTasks;

    public utlShared (String taskName , Boolean taskDone)
    {
        this.taskName=taskName;
        this.taskDone=taskDone;
    }

    public utlShared (Context context, String userName)
    {
        this.context=context;
        this.userName=userName;
        userPref=context.getSharedPreferences(userName, Context.MODE_PRIVATE);
        editor = userPref.edit();

        ArrayList<utlShared> myTasks = new ArrayList<utlShared>();
        getTasks();
    }

    public void newTask (String taskName)
    {
        editor.putString(taskName , "0");
        editor.commit();
        myTasks.add(new utlShared(taskName, false));
    }

    public void removeTask (String taskName)
    {
        editor.remove(taskName);
        editor.commit();
        myTasks.remove(taskName);
    }

    public void doneTask (String taskName , boolean taskDone)
    {
        editor.putString(taskName , taskDone ? "1" : "0");
        editor.commit();
        myTasks.remove(taskName);
        myTasks.add(new utlShared(taskName, taskDone));
    }

    public void getTasks ()
    {
        Map<String,?> tasks = userPref.getAll();
        for (Map.Entry<String,?> singleTask:tasks.entrySet())
        {
            myTasks.add(new utlShared(singleTask.getKey() , true));
        }
    }

    public ArrayList<utlShared> getAllTasks()
    {
        return myTasks;
    }
}


////////////////////////////////////////////////
            taskAdapter class
////////////////////////////////////////////////

package com.example.raz.mytasks;

import android.content.Context;
import android.graphics.Color;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.EditText;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by raz on 27/03/2016.
 */
public class taskAdapter extends BaseAdapter
{
    Context context;
    List<utlShared> myList;

    public taskAdapter(Context context, ArrayList<utlShared> myList)
    {
        this.context=context;
        this.myList=myList;
    }
    @Override
    public int getCount() {
        return myList.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final EditText txtTask = new EditText(context);
        txtTask.setText(myList.get(position).taskName);
        txtTask.setTextColor(myList.get(position).taskDone ? Color.GREEN : Color.RED);
        txtTask.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                txtTask.setTextColor(Color.GREEN);
            }
        });
        return txtTask;
    }
}