android - 关于android View 寻呼机中嵌套 fragment 中的回栈的问题

Question

我开发了一个有一个 Activity 的应用程序，在这个 Activity 中，抽屉中有很多 fragment ，在一个 fragment 中，我设置了 View 寻呼机来显示多个 fragment 实例，它的工作完美，但是当我在 View 寻呼机中打开另一个 fragment (嵌套 fragment )时，它工作但是当我按下后退按钮时它的整个应用程序关闭所以 fragment 管理器中的后退堆栈有什么问题我使用子 fragment 管理器所以我想要实现就像我按下它时打开前一个 fragment

我的代码是

    pageAdapter = new MyPageAdapter(getChildFragmentManager(), Global.DatabaseHandler.DisplayTempleList(), activityType);

        pager = (ViewPager) v.findViewById(R.id.pager);
        pager.setAdapter(pageAdapter);
        indicator = (TabPageIndicator) v.findViewById(R.id.indicator);
        indicator.setViewPager(pager);


        return v;
    }

//    private List<Fragment> getFragments() {
//
//        List<Fragment> fList = new ArrayList<Fragment>();
//        //TempleLists = Global.DatabaseHandler.DisplayTempleList();
//
//        for (TempleDetail templeDetail : TempleLists.Temple) {
//            if (activityType == Global.About) {
//                fList.add(new About_Fragment(templeDetail.temple_id, templeDetail.temple_name));
//            } else if (activityType == Global.DailyDarshan) {
//                fList.add(new DailyDarshan_Activity(templeDetail.temple_id, templeDetail.temple_name));
//            } else if (activityType == Global.PhotoGallery) {
//                fList.add(new PhotoGallery_Activity(templeDetail.temple_id, templeDetail.temple_name));
//            }
//        }
//
//        return fList;
//    }

    private class MyPageAdapter extends FragmentPagerAdapter {
        private HashMap<Integer, Fragment> fragments;
        private TempleList TempleLists;
        private String ActivityType;

        //public MyPageAdapter(FragmentManager fm, List<Fragment> fragments) {
        public MyPageAdapter(FragmentManager fm, TempleList templeList, String activityType) {
            super(fm);
            fragments = new HashMap<Integer, Fragment>();
            TempleLists = templeList;
            ActivityType = activityType;
        }

        @Override
        public Fragment getItem(int position) {

            if (!fragments.containsKey(position)) {
                Fragment fragment = new Sub_container(TempleLists.Temple.get(position).temple_id,
                        TempleLists.Temple.get(position).temple_name, ActivityType);
                fragments.put(position, fragment);
            }

            return this.fragments.get(position);
        }

        @Override
        public int getCount() {
            return TempleLists.Temple.size();
        }

        @Override
        public CharSequence getPageTitle(int position) {
            //return TempleLists.Temple.get(position % TempleLists.Temple.size()).temple_name.toUpperCase();
            return TempleLists.Temple.get(position).temple_name.toUpperCase();
        }
    }

}


other fragment 

         Fragment fragment = new FullImageActivity();

                FragmentTransaction transaction =  getFragmentManager ().beginTransaction();
                transaction.add(R.id.sub_container, fragment);
                transaction.addToBackStack(null);
                transaction.commit();

                Bundle args = new Bundle();
                args.putInt(Global.Id, position);
                args.putString(Global.TempleId, getArguments().getString(Global.TempleId));
                fragment.setArguments(args);

我的背压密码

    @Override
public void onBackPressed() {
    FragmentManager fragmentManager = getSupportFragmentManager();
    Log.i("-----------------", "---------------" + getFragmentManager().getBackStackEntryCount() + "---------");
    if (fragmentManager.getBackStackEntryCount() == 0) {
        if (doubleBackToExitPressedOnce) {

            super.onBackPressed();
            return;
        }
        this.doubleBackToExitPressedOnce = true;
        Global.interstitial.loadAd(Global.adRequest);
        Toast.makeText(this, "Press Again to Exit", Toast.LENGTH_SHORT).show();
    } else {
        fragmentManager.popBackStack();
        removeCurrentFragment();
    }
}

Answer 1

您必须在 backstack 中添加嵌套 fragment ，

 public void changePage(int id, Fragment frag) {

    String backStateName = frag.getClass().getName();
    changePage(id, frag, backStateName);
}



public void changePage(int id, Fragment frag, String backStateName) {

    imm.hideSoftInputFromWindow(backView.getWindowToken(), 0);

    transaction = fragmentManager.beginTransaction();

    transaction.setCustomAnimations(R.animator.righttoleft_1, R.animator.righttoleft_2, R.animator.lefttoright_1, R.animator.lefttoright_2);

    boolean fragmentPopped = fragmentManager.popBackStackImmediate (backStateName, 0);

     if (!fragmentPopped){ //fragment not in back stack, create it.

        transaction.replace(id, frag);
        transaction.addToBackStack(backStateName);
        transaction.commit();
      }

}

并将此代码添加到您的 Activity 中。

@Override
public void onBackPressed() {
    // TODO Auto-generated method stub


    if (fragmentManager.getBackStackEntryCount() > 1) {
        Log.i("MainActivity", "popping backstack");
        fragmentManager.popBackStack();
    } else {
        Log.i("MainActivity", "nothing on backstack, calling super");
        super.onBackPressed();
    }
}