我有一个MainActivity,它加载一个包含ViewPager的布局,其中包含三个片段(根据方向有不同的布局).

我已将此功能添加到活动中,因此当方向更改时它不会被销毁,因为我可能会打开一些对话框或弹出窗口：

android:configChanges="keyboardHidden|orientation|screenSize|screenLayout|uiMode"

因此,我已经覆盖了方法“onConfigurationChanged”,它只调用方法loadLayout,其中有关视图的所有内容：

private void loadLayout() {
    setContentView(R.layout.layout_main_activity);
 
    pager = (ViewPager) this.findViewById(R.id.pager);
    pager.setPageTransformer(true,new DepthPageTransformer());
 
    adapter = new MyFragmentPagerAdapter(getSupportFragmentManager());
    adapter.addFragment(Fragment1.getInstance());
    adapter.addFragment(Fragment2.getInstance());
    adapter.addFragment(Fragment3.getInstance());
 
    pager.setAdapter(adapter);
    pager.setOffscreenPageLimit(2);
 
    //Media controllers
    imgMediaController= (ImageButton) findViewById(R.id.media_controller);
 
    imgMediaController.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            [...]
        }
    });
 
    imgVolumeController= (ImageButton) findViewById(R.id.volume_controller);
    gM.setImgVolumeController(imgVolumeController);
 
    imgVolumeController.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            [...]
        }
    });
}

片段的代码是相同的：

public class FragmentNature extends Fragment {
 
private static FragmentNature instance;
private SoundManager sM;
private View rootView;
Hashtable<String,ImageButton> h_Images;
private Handler repeatUpdateHandler = new Handler();
private Toast volumeToast;
 
 
public static FragmentNature getInstance() {
    if (instance == null)
        instance = new FragmentNature();
    return instance;
}
 
public void nullInstance() {
    instance=null;
}
 
public FragmentNature(){
    h_Images=new Hashtable<String,ImageButton>();
}
 
public void onCreate(Bundle savedInstanceState) {
    Log.d("Naturing","On create->Estoy en el fragment nature");
    super.onActivityCreated(savedInstanceState);
    sM=SoundManager.getInstance();
}
 
public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
 
 
    rootView=null;
    Log.d("Naturing","On createView->Estoy en el fragment nature");
    rootView = inflater.inflate(R.layout.fragment_nature,container,false);
 
    final ImageButton imgRain= (ImageButton) rootView.findViewById(R.id.n_rain);
    h_Images.put("n_rain",imgRain);
    imgRain.setImageResource(R.drawable.n_rainsel);
 
    final ImageButton imgRiver= (ImageButton) rootView.findViewById(R.id.n_river);
    imgRiver.setImageResource(R.drawable.n_riversel);
 
    final ImageButton imgWave= (ImageButton) rootView.findViewById(R.id.n_wave);
    h_Images.put("n_wave",imgWave);
    imgWave.setImageResource(R.drawable.n_wavesel);
 
    final ImageButton imgWind= (ImageButton) rootView.findViewById(R.id.n_wind);
    h_Images.put("n_wind",imgWind);
    imgWind.setImageResource(R.drawable.n_windsel);
 
    final ImageButton imgFire= (ImageButton) rootView.findViewById(R.id.n_fire);
    h_Images.put("n_fire",imgFire);
    imgFire.setImageResource(R.drawable.n_firesel);
 
    final ImageButton imgTree= (ImageButton) rootView.findViewById(R.id.n_tree);
    h_Images.put("n_tree",imgTree);
    imgTree.setImageResource(R.drawable.n_treesel);
 
    final ImageButton imgStorm= (ImageButton) rootView.findViewById(R.id.n_storm);
    h_Images.put("n_storm",imgStorm);
    imgStorm.setImageResource(R.drawable.n_stormsel);
 
    final ImageButton imgDrop= (ImageButton) rootView.findViewById(R.id.n_drop);
    h_Images.put("n_drop",imgDrop);
    imgDrop.setImageResource(R.drawable.n_dropsel);
 
    final ImageButton imgDeepSea= (ImageButton) rootView.findViewById(R.id.n_deepsea);
    h_Images.put("n_deepsea",imgDeepSea);
    imgDeepSea.setImageResource(R.drawable.n_deepseasel);
 
    return rootView;
}
 
private boolean isNetworkAvailable(){
    Context context=ApplicationManager.getAppContext();
    ConnectivityManager connectivityManager=
            (ConnectivityManager) context.getSystemService(context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetworkInfo= connectivityManager.getActiveNetworkInfo();
    return activeNetworkInfo != null && activeNetworkInfo.isConnected();
}
 
public void changeImageStatus(String sound,int imgId){
    Log.d("Naturing","FragmentNature::changeImageStatus  | sound= " + sound + "  imgId=" + imgId);
    h_Images.get(sound).setImageResource(imgId);
}

}

问题是当方向改变时,mainActivity布局被正确加载,但viewPager不是.事实上,它消失了,在它的位置上看不到任何东西.无论如何,viewPager在那里,因为我能够通过它并到达终点(我知道这是因为当你到达菜单的末尾时我可以看到蓝色标志等等).

我也尝试调用片段的OncreateView方法但没有任何变化.

任何的想法？
谢谢和亲切的问候

编辑1

如果我取出“pager.setOffscreenPageLimit(2);”,在方向更改后,当我滚动viewpager一段时间时,片段1和片段3是可见的,但片段2在任何情况下都不会出现.我知道它并不多,但万一它会暗示任何人.

编辑2

如果我取出Manifest中的行,它可以正常工作,因为它调用MainActivity和Fragment的onCreateView.但是我需要清单中的那一行.

解决方法

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