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Ok, so i needed circular ViewPager. I was having really hard time to implement it. Now that i have implemented it and it is working fine as far as circular scroll is concern. But i have notice a problem.Which is, after first round of scroll fragments don't work. I have three Fragments with a button inside them. Button works in first round but when i come back to first page button doesn't work. p.s i used fake pages technique to make viewpager circular.

Here is code

        mViewPager.setAdapter(new PagerAdapter(getSupportFragmentManager(), this));
    //mViewPager.setOnPageChangeListener(new CircularViewPagerHandler(mViewPager));
    mViewPager.setCurrentItem(1, false);
    mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

        }

        @Override
        public void onPageSelected(int position) {
            if (position == 0) {
                mViewPager.setCurrentItem(3, false);
                Log.d("TAG",
                        "Swiped before first page, looping and resetting to last page.");
            } else if (position == 4) {
                mViewPager.setCurrentItem(1, false);
                Log.d("TAG",
                        "Swiped beyond last page, looping and resetting to first page.");
            }
        }

        @Override
        public void onPageScrollStateChanged(int state) {
            Log.d("onPageScrollState", "state:" + state);
            int currentPage = mViewPager.getCurrentItem();
            if(currentPage==1){
                imgCenter.setImageResource(R.drawable.take_ride);
                imgLeft.setImageResource(R.drawable.give_ride);
                imgRight.setImageResource(R.drawable.setting);
            }
            if(currentPage==2){
                imgCenter.setImageResource(R.drawable.setting);
                imgRight.setImageResource(R.drawable.take_ride);
                imgLeft.setImageResource(R.drawable.give_ride);
            }
            if (currentPage==3){
                imgCenter.setImageResource(R.drawable.give_ride);
                imgLeft.setImageResource(R.drawable.take_ride);
                imgRight.setImageResource(R.drawable.setting);

            }
        }
    });

here is PagerAdapter class

  public class PagerAdapter extends FragmentPagerAdapter {

Context mcontext;

public PagerAdapter(FragmentManager fm, Context context) {
    super(fm);
    mcontext = context;
}

@Override
public Fragment getItem(int position) {
    if (position == 0) {
        return new HomeFragment2();
    }
    else if(position==1){
        return new HomeFragment();
    }
    else if (position == 2) {
        return new SettingFragment();
    }
    else if(position==3){
        return new HomeFragment2();
    }
    else
        return new HomeFragment();
}

@Override
public int getCount() {
    return 5;
}
}
Zeeshan Shabbir
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  • Try these [How to do circular scrolling on ViewPager](http://stackoverflow.com/questions/21368693/how-to-do-circular-scrolling-on-viewpager), [CircularViewPager](https://github.com/TobiasBuchholz/CircularViewPager) – Archie.bpgc Dec 28 '15 at 06:34
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    Actually problem is with fragments. Fragments aren't functioning but circular scrolling is work. Fragment only work if i don't scroll in circular way – Zeeshan Shabbir Dec 28 '15 at 06:57

1 Answers1

4

I've created a simple test-app with you PagerAdapter and simple Fragments with a Button:

enter image description here

And it works fine!

I've uploaded the source code here, so you can check it out and see if there's any difference with yours.

As a Fragment's I used:

public class FragmentA extends android.support.v4.app.Fragment {

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_a, container, false);
        rootView.findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Snackbar.make(v, "Hi, fragment A", Snackbar.LENGTH_SHORT).show();
            }
        });
        return rootView;
    }
}

So what I can recommend

  • replace your fragments with some dummy ones (like the one above). If it works - the issue is in the Fragment code, not in the Circular ViewPager

  • If it still doesn't work - I'd try to instead of re-creating fragments multiple times - create them once and store:

     public class PagerAdapter extends FragmentPagerAdapter {
        Context mcontext;
        Fragment [] fragments;
        public PagerAdapter(FragmentManager fm, Context context, Fragment [] fragments) {
            super(fm);
            mcontext = context;
            this.fragments = fragments;
        }
    
        @Override
        public Fragment getItem(int position) {
            return fragments[position];
        }
    
        @Override
        public int getCount() {
            return fragments.length;
        }
    }
    

    And in Activity:

    Fragment[] fragments = {
            Fragment.instantiate(this, FragmentC.class.getName()),
            Fragment.instantiate(this, FragmentA.class.getName()),
            Fragment.instantiate(this, FragmentB.class.getName()),
            Fragment.instantiate(this, FragmentC.class.getName()),
            Fragment.instantiate(this, FragmentA.class.getName()),
    };
    .....
    viewPager.setAdapter(new PagerAdapter(getSupportFragmentManager(), this, fragments));
    

Let me know, if it helps!

Konstantin Loginov
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  • Thanks for answering. I will check on your solution if this works then i will accept your answer. – Zeeshan Shabbir Dec 30 '15 at 04:31
  • Why didn't you hand onClick event in OnActivityCreated(){} ? – Zeeshan Shabbir Dec 30 '15 at 04:48
  • Thanks it works. But now please explain. Why it wasn't working when i was firing button events inside onActivityCreated()? – Zeeshan Shabbir Dec 30 '15 at 07:30
  • Hi, @ZeeshanShabbir . I'm glad, that it worked for you. About `onActivityCreated()` - I can _suggest_, that it wasn't firing every time: In the Fragment's lifecycle, `onCreateView()` is getting called every time after `onStop()`, but `onActivityCreated()` only with some pre-conditions: http://2.bp.blogspot.com/-8nlybJW9w4Y/U2fEfDczGiI/AAAAAAAALAg/w6ZcaP91C2c/s1600/complete_android_fragment_lifecycle.png – Konstantin Loginov Dec 30 '15 at 08:42
  • Thanks much it really helped. I am really having hard time understanding how fragments work. – Zeeshan Shabbir Dec 30 '15 at 11:36
  • Sorry i didn't know how bounty works. I just got it know. Gave you bounty. – Zeeshan Shabbir Jan 05 '16 at 13:15