我使用了viewpager来制作tablayout。有三个标签'照片''视频''文件'。我刚刚完成了“照片”标签的编码。照片选项卡有一个GridView和Button，用于将图像上传到Gridview。单击该按钮时，系统会要求用户选择图库或单击图片并上传图像并将其显示在GridView上，但是当我旋转单元格时，gridview内容将消失。当我关闭应用程序并再次启动它时，以及当我选择文档片段并再次返回到照片片段时，也会发生同样的情况。 我搜索了很多，发现将使用getChildFragmentManager（）代替getSupportFragmentManager（）。但问题是我的MainActivity是一个Activity而不是Fragment，并且getChildFragmentManager（）不能在activity中使用。 这是代码..
// MainFragment.java //从此处设置Viewpager
公共类MainFragment扩展了Fragment {
private TabLayout tabLayout;
private static ViewPager viewPager;
private static FragmentManager fragmentManager;
private View view;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
view = inflater.inflate(R.layout.activity_main, container, false);
initUI();
return view;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
List<Fragment> fragments = getChildFragmentManager().getFragments();
if (fragments != null) {
for (Fragment fragment : fragments) {
fragment.onActivityResult(requestCode, resultCode, data);
}
}
}
private void initUI() {
viewPager = (ViewPager) view.findViewById(R.id.viewpager);
setupViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
fragmentManager = getChildFragmentManager();
ViewPagerAdapter adapter = new ViewPagerAdapter(fragmentManager);
viewPager.setAdapter(adapter);
}}
// PhotoFragment.java
公共类PhotoFragment扩展Fragment {
private FloatingActionButton fabPicture;
private GridView gridView;
private View view;
private Dialog dialog = null;
private int widthofwindow, heightofwindow;
private ImageView btnCameradialog, btnGalleryDialog, btnCamera;
private final int CLICK_PHOTO = 1;
private final int SELECT_PHOTO = 2;
private Uri imageUri;
private String path, picturePath, pathlist;
private List<PictureBeans> pictureDisplayList = null;
private ImageAdapter adapter;
public PhotoFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_photo, container, false);
initUI();
setListener();
return view;
}
private void initUI() {
btnCamera = (ImageView) view.findViewById(R.id.fabPicture);
gridView = (GridView) view.findViewById(R.id.grid_view);
DisplayMetrics metrics = getActivity().getResources().getDisplayMetrics();
widthofwindow = (int) (metrics.widthPixels * 0.85);
heightofwindow = (int) (metrics.widthPixels * 1);
pictureDisplayList = new ArrayList<>();
}
private void setListener() {
fabPicture.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
showappwindow();
}
});
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent i = new Intent(getActivity(), FullImageActivity.class);
i.putExtra("id", position);
i.putExtra("path", pictureDisplayList.get(position).getPicturePath().toString());
startActivity(i);
}
});
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent imageReturnedIntent) {
super.onActivityResult(requestCode, resultCode, imageReturnedIntent);
switch (requestCode) {
case SELECT_PHOTO:
if (resultCode == Activity.RESULT_OK) {
try {
imageUri = imageReturnedIntent.getData();
path = getRealPathFromURI(getActivity(), imageUri);
Log.v("Uri", "" + imageUri);
picturePath = path.toString();
Log.e("Picture Path in Frag ", "" + picturePath);
PictureBeans bean = new PictureBeans();
bean.setPicturePath(picturePath);
pictureDisplayList.add(bean);
Log.e("List size", "" + pictureDisplayList.size());
addToAdapter(pictureDisplayList);
} catch (Exception e) {
e.printStackTrace();
}
}
break;
case CLICK_PHOTO:
if (resultCode == Activity.RESULT_OK) {
try {
imageUri = imageReturnedIntent.getData();
path = getRealPathFromURI(getActivity(), imageUri);
picturePath = path.toString();
PictureBeans bean = new PictureBeans();
bean.setPicturePath(picturePath);
pictureDisplayList.add(bean);
addToAdapter(pictureDisplayList);
} catch (Exception e) {
e.printStackTrace();
}
}
break;
}
}
private void addToAdapter(List<PictureBeans> pictureDisplayList) {
adapter = new ImageAdapter(getActivity(), pictureDisplayList);
gridView.setAdapter(adapter);
}
public String getRealPathFromURI(Context context, Uri contentUri) {
Cursor cursor = null;
try {
String[] proj = {MediaStore.Images.Media.DATA};
cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
} finally {
if (cursor != null) {
cursor.close();
}
}
}
public void showappwindow() {
dialog = new Dialog(getActivity(), R.style.mydialogstyle);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.dialog_photo);
Window window = dialog.getWindow();
window.setLayout(widthofwindow, heightofwindow);
btnCameradialog = (ImageView) dialog.findViewById(R.id.btnCameradialog);
btnGalleryDialog = (ImageView) dialog.findViewById(R.id.btnGalleryDialog);
dialog.show();
btnCameradialog.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
getParentFragment().startActivityForResult(cameraIntent, CLICK_PHOTO);
dialog.dismiss();
}
});
btnGalleryDialog.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
photoPickerIntent.setType("image/*");
getParentFragment().startActivityForResult(photoPickerIntent, SELECT_PHOTO);
dialog.dismiss();
}
});
}}
// ViewPager Adapter
公共类ViewPagerAdapter扩展了FragmentPagerAdapter {
final int PAGE_COUNT = 3;
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
private PhotoFragment photoFragment;
private TwoFragment twoFragment;
private ThreeFragment threeFragment;
private String[] titles = new String[]{"Photo", "Video", "Documents"};
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
@Override
public Fragment getItem(int position) {
Bundle bundle = new Bundle();
bundle.putInt("request.code", position + 1);
switch (position) {
case 0:
photoFragment = new PhotoFragment();
return photoFragment;
case 1:
twoFragment = new TwoFragment();
return twoFragment;
case 2:
threeFragment = new ThreeFragment();
return threeFragment;
}
return null;
}
@Override
public int getCount() {
return PAGE_COUNT;
}
@Override
public CharSequence getPageTitle(int position) {
return titles[position];
}}