Why doesn't the data from my database update in Android Studio?

I think my SQL queries is working but the data of my table is not updating. Why is that?

I have a table in my database named MasterStudents with column names StudentID INTEGER NOT NULL UNIQUE, FirstName VARCHAR, LastName VARCHAR, ContactNumber VARCHAR, EmailAddress VARCHAR

I have two classes, StudentsMasterList.java - makes a Table layout that display data in a database using a Table Row & StudentsFormUpdate.java that retrieves the data of the selected Table Row and displays it in EditText/s.

I have a button in the StudentsFormUpdate that calls the function UpdateButton() onClick.

This is the StudentsMasterList.java class:

public class StudentsMasterList extends Activity
{
    SQLiteDatabase db;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {

        super.onCreate(savedInstanceState);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.students_masterlist);
        db=openOrCreateDatabase("ClassManager",MODE_WORLD_WRITEABLE, null);


        final Cursor c=db.rawQuery("SELECT * FROM MasterStudents ORDER BY LastName", null);
        int count= c.getCount();
        c.moveToFirst();
        TableLayout tableLayout = new TableLayout(getApplicationContext());
        tableLayout.setVerticalScrollBarEnabled(true);
        TableRow tableRow;
        TextView textView, textView1 = null;

        RelativeLayout rl = (RelativeLayout)findViewById(R.id.layout);
        ScrollView sv = new ScrollView (this);
        sv.addView(tableLayout);
        rl.addView(sv, new WindowManager.LayoutParams(WindowManager.LayoutParams.FILL_PARENT, WindowManager.LayoutParams.FILL_PARENT));

        for (Integer j = 0; j < count; j++)
        {

            tableRow = new TableRow(getApplicationContext());
            textView1 = new TextView(getApplicationContext());
            textView1.setText(c.getString(c.getColumnIndex("StudentID")));
            textView1.setPadding(20, 20, 20, 20);
            textView1.setTextColor(getResources().getColor(R.color.blueactionbar));
            textView1.setTextSize(TypedValue.COMPLEX_UNIT_DIP,25);
            textView1.setTypeface(null, Typeface.BOLD);
            tableRow.addView(textView1);

            tableRow.setClickable(true);

            final String container = textView1.getText().toString();
            tableRow.setOnClickListener(new View.OnClickListener()
            {
                @Override
                public void onClick(View view)
                {
                    Intent StudentUpdateScreenIntent = new Intent (view.getContext(), StudentsFormUpdate.class);

                    StudentUpdateScreenIntent.putExtra("sender", container);

                    startActivity(StudentUpdateScreenIntent);

                    overridePendingTransition(R.anim.transition,R.anim.right2left);

                }
            });

            textView = new TextView(getApplicationContext());
            textView.setText(c.getString(c.getColumnIndex("LastName")));
            textView.setPadding(20, 20, 20, 20);
            textView.setTextColor(getResources().getColor(R.color.blueactionbar));
            textView.setTextSize(TypedValue.COMPLEX_UNIT_DIP,25);
            textView.setTypeface(null, Typeface.BOLD);
            tableRow.addView(textView);
            tableLayout.addView(tableRow);
            c.moveToNext() ;
        }
        db.close();
        rl.requestLayout();


    }

}

This is the StudentsFormUpdate.java class:

public class StudentsFormUpdate extends Activity
{
    String FirstName, LastName, EmailAddress, ContactNumber, StudentID;
    SQLiteDatabase db;

    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.students_updateform);
        db = openOrCreateDatabase("ClassManager", MODE_WORLD_READABLE, null);

        String reciever = getIntent().getStringExtra("sender");

        Cursor c = db.rawQuery("SELECT * FROM MasterStudents WHERE StudentID = '" + reciever + "'", null);

        TextView StudentIDViewUpdate2  = (TextView)findViewById(R.id.StudentIDViewPermanentUpdate);
        EditText FirstNameUpdate2      = (EditText)findViewById(R.id.FirstNameTextUpdate);
        EditText LastNameUpdate2       = (EditText)findViewById(R.id.LastNameTextUpdate);
        EditText ContactNumberUpdate2  = (EditText)findViewById(R.id.ContactNumberTextUpdate);
        EditText EmailUpdate2          = (EditText)findViewById(R.id.EmailAddressTextUpdate);


        c.moveToFirst();
        StudentIDViewUpdate2.setText(c.getString(c.getColumnIndex("StudentID")));
        FirstNameUpdate2.setText(c.getString(c.getColumnIndex("FirstName")));
        LastNameUpdate2.setText(c.getString(c.getColumnIndex("LastName")));
        ContactNumberUpdate2.setText(c.getString(c.getColumnIndex("ContactNumber")));
        EmailUpdate2.setText(c.getString(c.getColumnIndex("EmailAddress")));

        StudentID = StudentIDViewUpdate2.getText().toString();
        FirstName = FirstNameUpdate2.getText().toString();
        LastName = LastNameUpdate2.getText().toString();
        ContactNumber = ContactNumberUpdate2.getText().toString();
        EmailAddress = EmailUpdate2.getText().toString();

    }

    public void UpdateButton(View view)
    {
        db.execSQL("UPDATE MasterStudents SET FirstName = '" + FirstName + "', LastName = '" + LastName + "', ContactNumber = '" + ContactNumber + "', " +
                   "EmailAddress = '" + EmailAddress + "' WHERE StudentID = '" + StudentID + "'");

        Toast toast = Toast.makeText(getApplicationContext(), "Student Updated", Toast.LENGTH_SHORT);
        toast.show();
        finish();
    }

Why isn't my code working? Any help is highly appreciated!