我有一个viewpager在一个片段中,我显示了3个片段,但是当我第一次打开片段时,它打开的很好,当我移动到另一个片段并返回到viewpager片段时,它不会在查看寻呼机中不显示片段,然后我必须改变手机的方向,或者不断刷看视图,以显示隐藏的片段。保留viewpager片段的状态android
我用Google搜索它,现在我知道我要的标签设置为每个片段并用findfragmentbytag方法来检索片段,但问题是,当我尝试设置标签片段
getSupportFragmentManager().beginTransaction().add(myFragment, "Some Tag").commit();
上面一行崩溃我应用程序和logcat显示“不能设置标记到片段”,我知道我在做一些愚蠢的错误
这是我的片段的完整代码。如果能指导我在哪里编写用于设置片段标签的代码,我将非常感激。提前致谢。
public class MatchesListingFragment extends Fragment implements ActionBar.TabListener {
Context context;
SectionsPagerAdapter mSectionsPagerAdapter;
ViewPager mViewPager;
ActionBar actionBar;
Matchlistings db;
Bundle savedInstanceState;
Fragment livescore,fixture,results;
@Override
public void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
this.savedInstanceState = savedInstanceState;
db = new Matchlistings(getActivity());
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_matches, container, false);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
context = getActivity().getApplicationContext();
if(savedInstanceState == null){
livescore = new LiveScoreListingFragment();
fixture = new FixturesListingFragment();
results = new ResultsListingFragment();
}
if(!Constants.is_listing_refreshed){
Log.i(MainActivity.TAG,"refreshing list");
db.loadListingsFromServer().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
}
actionBar = getActivity().getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
if(mSectionsPagerAdapter == null)
mSectionsPagerAdapter = new SectionsPagerAdapter(getActivity().getSupportFragmentManager());
mViewPager = (ViewPager) getView().findViewById(R.id.pager);
mViewPager.setAdapter(mSectionsPagerAdapter);
mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
for (int i = 0; i < mSectionsPagerAdapter.getCount(); i++) {
Tab tb = actionBar.newTab()
.setText(mSectionsPagerAdapter.getPageTitle(i))
.setTabListener(this);
actionBar.addTab(tb);
}
}
public class SectionsPagerAdapter extends FragmentPagerAdapter {
Fragment fragment;
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
switch(position){
case 0:
fragment = livescore;
return fragment;
case 1:
fragment = fixture;
return fragment;
case 2:
fragment = results;
return fragment;
case 3:
fragment = new LiveScoreListingFragment();
return fragment;
}
return null;
}
@Override
public int getCount() {
return 4;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "LIVE";
case 1:
return "FIXTURES";
case 2:
return "RESULTS";
case 3:
return "HOT";
}
return null;
}
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
actionBar.removeAllTabs();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
}
@Override
public void onTabReselected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
@Override
public void onTabSelected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
@Override
public void onTabUnselected(Tab arg0, FragmentTransaction arg1) {
// TODO Auto-generated method stub
}
}
编辑: 我现在已经试图通过标签来得到viewpager的片段,而不是创造新的片段,每次的。但问题仍然是一样的。
FixturesListingFragment fixture = (FixturesListingFragment) getActivity().getSupportFragmentManager().findFragmentByTag("android:switcher:"+R.id.pager+":1");
if(fixture == null)
fixture = new FixturesListingFragment();
FragmentPagerAdapter使用标签本身 – MGDroid
我该如何使用它来获取片段? –