Observer pattern for notifying Fragments of a ViewPager to update their views. This will update the current Fragment, as well as the off screen Fragments that are retained.

FragmentObserver.java

public class FragmentObserver extends Observable {
    @Override
    public void notifyObservers() {
        setChanged(); // Set the changed flag to true, otherwise observers won't be notified.
        super.notifyObservers();
    }
}

MyActivity.java

public class MyActivity extends Activity {
    private MyAdapter mPagerAdapter;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        setContentView(R.layout.my_activity);
        ViewPager pager = (ViewPager) findViewById(R.id.pager);
        mPagerAdapter = new MyAdapter();
        pager.setAdapter(mPagerAdapter);
    }
    
    private void updateFragments() {
        mPagerAdapter.updateFragments();
    }
}

MyAdapter.java

public class MyAdapter extends FragmentPagerAdapter {
    private Observable mObservers = new FragmentObserver();

    public MyAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        mObservers.deleteObservers(); // Clear existing observers.
        Fragment fragment = new MyFragment();
        if(fragment instanceof Observer)
            mObservers.addObserver((Observer) fragment);

        return fragment;
    }

    public void updateFragments() {
        mObservers.notifyObservers();
    }
}

MyFragment.java

public class MyFragment extends Fragment implements Observer {

    /* Fragment related stuff... */

    @Override
    public void update(Observable observable, Object data) {
        View root = getView();
        // Update your views here.
    }
}

How can we send array list through object like here
public void updateFragments() {
mObservers.notifyObservers(); // <-- here
}
and access it in MyFragment -> update(Observable observable, Object data) ??

Thanks Man! You Save my Day

Work fine! For notify all fragments remove mObservers.deleteObservers. Work great for me.
For notify with object change your implementation of FragmentObserver:

public class FragmentObserver extends Observable {
    @Override
    public void notifyObservers(object: Object) {
        setChanged(); // Set the changed flag to true, otherwise observers won't be notified.
        super.notifyObservers(object);
    }
}

In Kotlin:

class FragmentObserver : Observable() {

override fun notifyObservers(arg: Any?) {
setChanged(); // Set the changed flag to true, otherwise observers won't be notified.
super.notifyObservers(arg)
}

}