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我有问题FragmentPagerAdapter，我已经通过FragmentPagerAdapter设置在viewpager片段， 我有动态地显示viewpager，我有列表视图数据，这是我需要显示在viewpager， 当我点击列表视图时，我不得不加载视图中的确切位置 所以我只是设置项目的总大小显示在FragmentPagerAdapter，但问题是，当我通过mPager.setCurrentItem(listposition)选择viewpager位置显示视图的正确位置， 但数据加载错误的地方，它加载在viewpager位置下一个fragement，在FragmentPagerAdapter中的一些跟踪后，我表明我nstantiateItem方法提前初始化一个片段，就像我设置viewpager 2的当前项目（从列表视图）然后instantiateItem方法initalize 0到3片段，我认为数据加载到第三个片段的原因，我也尝试了很多与FragmentStatePagerAdapter但也没有任何成功，请帮助我，在此先感谢。的Android Viewpager.setCurrentitem（）和FragmentPagerAdapter instantiateItem（）片段initailize失配
MainActivity类别（Fragmnetactivity）：
public class NewsDetail extends FragmentActivity implements OnClickListener {
public static ViewPager mPager;
private static int NUM_PAGES;
private PagerAdapter mPagerAdapter;
public static ArrayList<Integer> exist_detail = new ArrayList<Integer>();
public static ArrayList<PageFragment> detailfragment = new ArrayList<PageFragment>();
mPager = (ViewPager) findViewById(R.id.pager);
mPagerAdapter = new ScreenSlidePagerAdapter(getSupportFragmentManager());
mPager.setAdapter(mPagerAdapter);
NUM_PAGES = topList.size();
PageFragment fragment = new PageFragment();
Bundle args = new Bundle();
args.putInt("page", i);
fragment.setArguments(args);
detailfragment.add(fragment);
mPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int arg0) {
if (PageFragment.getInstance() != null) {
Log.d("LOG","PageFragment || "+ PageFragment.getInstance());
PageFragment.getInstance().startLoadingNews(
MusicList.topMusicList.get(arg0)._id);
}
return;
}
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {}
@Override
public void onPageScrollStateChanged(int arg0) {}
});
mPagerAdapter.notifyDataSetChanged();
mPager.setCurrentItem(listposition);// setcurrent item from here , it is selected from list. "listposition" indicate list position click
private class ScreenSlidePagerAdapter extends FragmentPagerAdapter {
private FragmentManager mFragmentManager;
private FragmentTransaction mCurTransaction = null;
private Fragment mCurrentPrimaryItem = null;
private static final boolean DEBUG = false;
public ScreenSlidePagerAdapter(FragmentManager fragmentManager) {
super(fragmentManager);
this.mFragmentManager = fragmentManager;
}
@Override
public Fragment getItem(int position) {
return detailfragment.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return super.getItemId(position);
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
Log.v("LOG", "On InstantiateItem " + position);// it indicate that this method initialize one fragment in advance.
return super.instantiateItem(container, position);
}
public String makeFragmentName(int viewId, long index) {
return "android:switcher:" + viewId + ":" + index;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
if (mCurTransaction == null) {
mCurTransaction = mFragmentManager.beginTransaction();
}
if (DEBUG)
Log.e("LOG", "Detaching item #" + position + ": f=" + object
+ " v=" + ((Fragment) object).getView());
mCurTransaction.detach((Fragment) object);
}
@Override
public void restoreState(Parcelable state, ClassLoader loader) {
}
@Override
public int getCount() {
return NUM_PAGES;
}
}
}
PageFragment
public class PageFragment extends Fragment implements OnClickListener {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mPageNumber = getArguments().getInt(ARG_PAGE);
mDetailPageFragment = this;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout containing a title and body text.
rootView = (ViewGroup) inflater.inflate(R.layout.newsdetail, container,
false);
//init();
return rootView;
}
public void startLoadingNews(String _id) {
if (NetworkUtil.cheackNetwork(mActivity)) {
executeTask(_id);
} else {
showRetryCancelDialog();
}
}
}