private void pickNextPiece() {
		Random random = new Random();
		int pickedNumber = random.nextInt(numberOfDifferentPieces);
		switch(pickedNumber) {
		case 0: activePiece = new ITetrisPiece();
			break;
		case 1: activePiece = new OTetrisPiece();
			break;
		case 2: activePiece = new JTetrisPiece();
			break;
		case 3: activePiece = new LTetrisPiece();
			break;
		case 4: activePiece = new STetrisPiece();
			break;
		case 5: activePiece = new ZTetrisPiece();
			break;
		case 6: activePiece = new TTetrisPiece();
			break;
		}
	}