fragment to activity typecasting
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
if (position == 0) {
openBottomSheetForScanning();
} else if (position == 1) {
((ReturnCrateFragment) adapter.getItem(position)).openBottomSheetForScanning();
}
}
@Override
public void onPageScrollStateChanged(int state) {
}
});