public class FlashCardActivity extends AppCompatActivity {

    FlashCardsDeck mTestDeck = new FlashCardsDeck();
    int currentPosition = 0;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.flashcards_layout);


        mTestDeck.addCard(new FlashCard("black", "czarny"));
        mTestDeck.addCard(new FlashCard("red", "czerwony"));
        mTestDeck.addCard(new FlashCard("yellow", "zolty"));
        mTestDeck.addCard(new FlashCard("green", "zielony"));
        mTestDeck.addCard(new FlashCard("white", "bialy"));

        // shuffles the deck so cards appear randomly

        mTestDeck.shuffle();

        setCurrentCard();

    }

    // sets the text of myTextView so each time after pressing one of two buttons there is a different flashcard

    private void setCurrentCard(){
        final FlashCard currentCard = mTestDeck.get(currentPosition);

        final TextView myTextView = (TextView) findViewById(R.id.flashcard_text_view);

        Button knowAnswerButton = (Button) findViewById(R.id.know_answer);

        Button dontKnowAnswerButton = (Button) findViewById(R.id.dont_know_answer);

        myTextView.setText(currentCard.getFront());

        knowAnswerButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (currentPosition > mTestDeck.size()){
                        mTestDeck.correctAnswer();
                }

                currentPosition++;
                setCurrentCard();
            }
        });

        dontKnowAnswerButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if(currentPosition > mTestDeck.size()){
                    myTextView.setText(currentCard.getBack());
                }

                currentPosition++;
                setCurrentCard();
            }
        });
    }
}