I am using ViewPager with some Fragments. I would like to achieve the next little effect: if I swipe to the very first page of the viewpager (so the index of the page equals 0), i would like to recreate it. So I do not want it to be pulled from the memory, I would like like to recreate it every time I swipe to that page. I read that I needed to override the instantiateItem method, but I cannot do it.
public class PagerAdapter1 extends FragmentPagerAdapter {
private List<String> fragments;
private static final String TAG = "FragmentPagerAdapter";
private static final boolean DEBUG = false;
private final FragmentManager mFragmentManager;
private FragmentTransaction mCurTransaction = null;
/**
* @param fm
* @param fragments2
*/
public PagerAdapter1(FragmentManager fm, List<String> fragments2) {
super(fm);
mFragmentManager=fm;
this.fragments = fragments2;
}
/* (non-Javadoc)
* @see android.support.v4.app.FragmentPagerAdapter#getItem(int)
*/
@Override
public Fragment getItem(int position) {
//return this.fragments.get(position);
return Fragment.instantiate(ViewPagerActivity.context, fragments.get(position));
}
/* (non-Javadoc)
* @see android.support.v4.view.PagerAdapter#getCount()
*/
@Override
public int getCount() {
return this.fragments.size();
}
@Override
public Object instantiateItem(View container, int position) {
Log.i("OVERRIDE", "OVERRIDE");
if (mCurTransaction == null) {
mCurTransaction = mFragmentManager.beginTransaction();
}
// Do we already have this fragment?
String name = makeFragmentName(container.getId(), position);
Fragment fragment = mFragmentManager.findFragmentByTag(name);
if (fragment != null) {
if (DEBUG) Log.v(TAG, "Attaching item #" + position + ": f=" + fragment);
mCurTransaction.attach(fragment);
} else {
fragment = getItem(position);
if (DEBUG) Log.v(TAG, "Adding item #" + position + ": f=" + fragment);
mCurTransaction.add(container.getId(), fragment,
makeFragmentName(container.getId(), position));
}
return fragment;
}
private static String makeFragmentName(int viewId, int index) {
return "android:switcher:" + viewId + ":" + index;
}
}
I never get the OVERRIDE tag. So my first question is, why dont I get that? And how should I rewrite this method (if this is what I need) to achieve the effect I wrote previously? I want it because I save a state of a checkbox at the page 0, but the optimisation twists it because the page 0 dont get destroyed if I swipe onto page 1, so it does not recreate it and a state of the checkbox dont get saved (unless I swipe to page2, beacuse I use setOffScreenLimit(1)).
