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androidandroid-fragmentsscreen-rotationratingbar

Fragment Containing RatingBar Triggers onRatingChanged on Rotation


I've got an activity that implements ActionBar.TabListener to provide 3 tabs for navigation. In one of the tabs I've introduced a RatingBar for rating of the element. Currently, changing the rating triggers a toast confirming the rating selected.

When rotating the orientation of the device, this toast is triggered again, even though the rating has not changed - I know I am probably redrawing the fragment for this tab (though in that case I do not understand why the rating persists) but I don't understand how to stop it. I tried to check the SavedInstanceState in OnCreateView but if I only apply the listener when it is not null, rotating the device removes the listener completely.

Activity onCreate

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_view_pub);

    Intent intent = getIntent();

    pubname = intent.getStringExtra(MainActivity.PUB);

    setTitle(pubname);

    final ActionBar actionBar = getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    mSectionsPagerAdapter = new SectionsPagerAdapter(getFragmentManager());

    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                actionBar.setSelectedNavigationItem(position);
            }
        });

    // For each of the sections in the app, add a tab to the action bar.
    for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
        actionBar.addTab(actionBar.newTab()
                .setText(mSectionsPagerAdapter.getPageTitle(i))
                .setTabListener(this));
    }

    actionBar.setSelectedNavigationItem(1);
}

FragmentPAgerAdapter Class

public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

    @Override
    public Fragment getItem(int position) {
        switch (position) {
            case 0:
                return DirectionsFragment.newInstance(position + 1);
            case 1:
                return DetailsFragment.newInstance(position + 1);
            case 2:
                return RelationsFragment.newInstance(position + 1);
        }
        return null;            
    }

    @Override
    public int getCount() {
        return 3;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        switch (position) {
            case 0:
                return getString(R.string.title_section1);
            case 1:
                return getString(R.string.title_section2);
            case 2:
                return getString(R.string.title_section3);
        }
        return null;
    }
}

DetailsFragment Class

public static class DetailsFragment extends Fragment {

    private static final String ARG_SECTION_NUMBER = "section_number";

    public static DetailsFragment newInstance(int sectionNumber) {
        DetailsFragment fragment = new DetailsFragment();
        Bundle args = new Bundle();
        args.putInt(ARG_SECTION_NUMBER, sectionNumber);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setRetainInstance(true);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        super.onCreateView(inflater, container, savedInstanceState);

        View rootView = inflater.inflate(R.layout.fragment_pub_details, container, false);
        RatingBar ratingBar = (RatingBar)rootView.findViewById(R.id.rating);
        ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener(){
            public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) {

                Toast.makeText(ratingBar.getContext(),"Your Selected Ratings  : " + String.valueOf(rating),Toast.LENGTH_LONG).show();

            }
        });
        return rootView;

    }
}

What obvious trick have I missed?


Solution

  • OK, so I've altered the onRatingChanged function to only fire it's contents if the fromUser boolean is true - obviously when the system redraws the tab it's then not firing the toast;

    ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener(){
        public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) {
            if(fromUser){
                Toast.makeText(ratingBar.getContext(),"Your Selected Ratings  : " + String.valueOf(rating),Toast.LENGTH_LONG).show();
            } 
        }
    });
    

    What I'm uncomfortable with is that I don't know if this is a hack, or if this is intended android process - my tabs are clearly being destroyed and rebuilt - is this for layout purposes or is my implementation flawed?

    I'm struggling to understand best practice so please feel free to point out the 'right way' if this is not it.