private void propagateScroll(int scrollY) {
// Set scrollY for the fragments that are not created yet
mPagerAdapter.setScrollY(scrollY);
// Set scrollY for the active fragments
for (int i = 0; i < mPagerAdapter.getCount(); i++) {
// Skip current item
if (i == mPager.getCurrentItem()) {
continue;
}
// Skip destroyed or not created item
FlexibleSpaceWithImageBaseFragment f =
(FlexibleSpaceWithImageBaseFragment) mPagerAdapter.getItemAt(i);
if (f == null) {
continue;
}
View view = f.getView();
if (view == null) {
continue;
}
f.setScrollY(scrollY, mFlexibleSpaceHeight);
f.updateFlexibleSpace(scrollY);
}
}
private View prepareMenuView(View view, Bundle savedInstanceState) {
mNavigationAdapter = new NavigationAdapter();
mNavigationAdapter.add(MainFragment.class, R.string.demo);
mNavigationAdapter.add(SettingsFragment.class, R.string.settings);
mNavigationAdapter.add(OtherFragment.class, R.string.other);
mNavigationAdapter.add(AboutFragment.class, R.string.about);
mNavigationAdapter.onItemSelected(mCurrentPage, mFirstRun);
ListView list = (ListView) view.findViewById(R.id.list);
list.setAdapter(mNavigationAdapter);
list.setOnItemClickListener(mNavigationAdapter);
return view;
}
public void onScrollChanged(int scrollY, Scrollable s) {
FlexibleSpaceWithImageBaseFragment fragment =
(FlexibleSpaceWithImageBaseFragment) mPagerAdapter.getItemAt(mPager.getCurrentItem());
if (fragment == null) {
return;
}
View view = fragment.getView();
if (view == null) {
return;
}
Scrollable scrollable = (Scrollable) view.findViewById(R.id.scroll);
if (scrollable == null) {
return;
}
if (scrollable == s) {
// This method is called by not only the current fragment but also other fragments
// when their scrollY is changed.
// So we need to check the caller(S) is the current fragment.
int adjustedScrollY = Math.min(scrollY, mFlexibleSpaceHeight - mTabHeight);
translateTab(adjustedScrollY, false);
propagateScroll(adjustedScrollY);
}
}