我有問題FragmentPagerAdapter
,我已經通過FragmentPagerAdapter
設置在viewpager片段, 我有動態地顯示viewpager,我有列表視圖數據,這是我需要顯示在viewpager, 當我點擊列表視圖時,我不得不加載視圖中的確切位置 所以我只是設置項目的總大小顯示在FragmentPagerAdapter,但問題是,當我通過mPager.setCurrentItem(listposition)
選擇viewpager位置顯示視圖的正確位置, 但數據加載錯誤的地方,它加載在viewpager位置下一個fragement,在FragmentPagerAdapter中的一些跟蹤後,我表明我nstantiateItem方法提前初始化一個片段,就像我設置viewpager 2的當前項目(從列表視圖)然後instantiateItem方法initalize 0到3片段,我認爲數據加載到第三個片段的原因,我也嘗試了很多與FragmentStatePagerAdapter但也沒有任何成功,請幫助我,在此先感謝。的Android Viewpager.setCurrentitem()和FragmentPagerAdapter instantiateItem()片段initailize失配
MainActivity類別(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();
}
}
}