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?
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.