Merge pull request #4521 from ByteHamster/generate-unique-ids
Generate unique view IDs
This commit is contained in:
commit
e4a714f2f4
|
@ -19,6 +19,7 @@ import androidx.annotation.Nullable;
|
|||
import androidx.appcompat.app.ActionBarDrawerToggle;
|
||||
import androidx.appcompat.app.AlertDialog;
|
||||
import androidx.appcompat.widget.Toolbar;
|
||||
import androidx.core.view.ViewCompat;
|
||||
import androidx.drawerlayout.widget.DrawerLayout;
|
||||
import androidx.fragment.app.Fragment;
|
||||
import androidx.fragment.app.FragmentManager;
|
||||
|
@ -67,6 +68,7 @@ public class MainActivity extends CastEnabledActivity {
|
|||
public static final String EXTRA_FEED_ID = "fragment_feed_id";
|
||||
public static final String EXTRA_OPEN_PLAYER = "open_player";
|
||||
public static final String EXTRA_REFRESH_ON_START = "refresh_on_start";
|
||||
public static final String KEY_GENERATED_VIEW_ID = "generated_view_id";
|
||||
|
||||
private DrawerLayout drawerLayout;
|
||||
private View navDrawer;
|
||||
|
@ -88,6 +90,9 @@ public class MainActivity extends CastEnabledActivity {
|
|||
public void onCreate(Bundle savedInstanceState) {
|
||||
lastTheme = UserPreferences.getNoTitleTheme();
|
||||
setTheme(lastTheme);
|
||||
if (savedInstanceState != null) {
|
||||
ensureGeneratedViewIdGreaterThan(savedInstanceState.getInt(KEY_GENERATED_VIEW_ID, 0));
|
||||
}
|
||||
super.onCreate(savedInstanceState);
|
||||
StorageUtils.checkStorageAvailability(this);
|
||||
setContentView(R.layout.main);
|
||||
|
@ -132,6 +137,25 @@ public class MainActivity extends CastEnabledActivity {
|
|||
sheetBehavior.setBottomSheetCallback(bottomSheetCallback);
|
||||
}
|
||||
|
||||
/**
|
||||
* ViewCompat.generateViewId stores the current ID in a static variable.
|
||||
* When the process is killed, the variable gets reset.
|
||||
* This makes sure that we do not get ID collisions
|
||||
* and therefore errors when trying to restore state from another view.
|
||||
*/
|
||||
@SuppressWarnings("StatementWithEmptyBody")
|
||||
private void ensureGeneratedViewIdGreaterThan(int minimum) {
|
||||
while (ViewCompat.generateViewId() <= minimum) {
|
||||
// Generate new IDs
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
protected void onSaveInstanceState(@NonNull Bundle outState) {
|
||||
super.onSaveInstanceState(outState);
|
||||
outState.putInt(KEY_GENERATED_VIEW_ID, ViewCompat.generateViewId());
|
||||
}
|
||||
|
||||
private BottomSheetBehavior.BottomSheetCallback bottomSheetCallback =
|
||||
new BottomSheetBehavior.BottomSheetCallback() {
|
||||
@Override
|
||||
|
|
|
@ -38,6 +38,8 @@ import io.reactivex.schedulers.Schedulers;
|
|||
public class ItemPagerFragment extends Fragment {
|
||||
private static final String ARG_FEEDITEMS = "feeditems";
|
||||
private static final String ARG_FEEDITEM_POS = "feeditem_pos";
|
||||
private static final String KEY_PAGER_ID = "pager_id";
|
||||
private ViewPager2 pager;
|
||||
|
||||
/**
|
||||
* Creates a new instance of an ItemPagerFragment.
|
||||
|
@ -77,12 +79,16 @@ public class ItemPagerFragment extends Fragment {
|
|||
feedItems = getArguments().getLongArray(ARG_FEEDITEMS);
|
||||
int feedItemPos = getArguments().getInt(ARG_FEEDITEM_POS);
|
||||
|
||||
ViewPager2 pager = layout.findViewById(R.id.pager);
|
||||
pager = layout.findViewById(R.id.pager);
|
||||
// FragmentStatePagerAdapter documentation:
|
||||
// > When using FragmentStatePagerAdapter the host ViewPager must have a valid ID set.
|
||||
// When opening multiple ItemPagerFragments by clicking "item" -> "visit podcast" -> "item" -> etc,
|
||||
// the ID is no longer unique and FragmentStatePagerAdapter does not display any pages.
|
||||
int newId = ViewCompat.generateViewId();
|
||||
if (savedInstanceState != null && savedInstanceState.getInt(KEY_PAGER_ID, 0) != 0) {
|
||||
// Restore state by using the same ID as before. ID collisions are prevented in MainActivity.
|
||||
newId = savedInstanceState.getInt(KEY_PAGER_ID, 0);
|
||||
}
|
||||
pager.setId(newId);
|
||||
pager.setAdapter(new ItemPagerAdapter(this));
|
||||
pager.setCurrentItem(feedItemPos, false);
|
||||
|
@ -99,6 +105,12 @@ public class ItemPagerFragment extends Fragment {
|
|||
return layout;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void onSaveInstanceState(@NonNull Bundle outState) {
|
||||
super.onSaveInstanceState(outState);
|
||||
outState.putInt(KEY_PAGER_ID, pager.getId());
|
||||
}
|
||||
|
||||
@Override
|
||||
public void onDestroyView() {
|
||||
super.onDestroyView();
|
||||
|
|
Loading…
Reference in New Issue