private void setPreviousNavigationButton() {
        ivPrevious = (ImageView) flNavigationButtons.findViewById(R.id.iv_previous_month);
        ivPrevious.setImageResource(settingsManager.getPreviousMonthIconRes());
        ivPrevious.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                goToPreviousMonth();
            }
        });
    }
Creates Next/Previous buttons to navigate months.
Visible only in HORIZONTAL mode
cosmocalendar/src/main/java/com/applikeysolutions/cosmocalendar/view/CalendarView.java