之前有人问过类似的问题，但我的情况不同。
我的应用程序中到处都是 DialogFragments。当我旋转手机时，除了这个之外，所有的 DialogFragments 都没有问题地返回。
我已经在生命周期回调中添加了 Log 消息，以查看发生了什么，这就是场景：
- 我的 DialogFragment 已创建并显示
- 在轮换时，我将任何我想要的东西保存到一个包中以便之后恢复。
- DialogFragment 已成功重新创建。我知道是因为调用了 onCreate 到 onResume 。
- 在恢复之后，由于某种莫名其妙的原因，onPause、onStop、onDestroyView、onDestroy 和 onDetach 立即被快速连续调用。DialogFragment 在重新创建后立即被销毁，我不知道为什么。
任何帮助深表感谢。DialogFragment 为结果启动一个活动以拍照。它适用于大多数手机，但 Galaxy S3 摄像头会导致方向更改，从而强制重新创建活动。我不介意，我知道如何处理活动娱乐，但我从未遇到过。
DialogFragment 是通过 RecyclerView 适配器回调从主托管活动中的常规片段启动的。
我没有在托管 RecyclerView 的片段中使用 ChildFragmentManger 显示 DialogFragment，因为多个片段可以显示此 DialogFragment 并且功能始终相同。无论哪个片段启动它，让活动接收回调更为谨慎。
从片段：
selectionPickAdapter.setAdapterListener(new selectionPickAdapter.AdapterListener() {
@Override
public void onSelectionClicked(Selection selection) {
if (getActivity() instanceof RankingActivity) {
((RankingActivity) getActivity()).onSelectionClicked(selection);
}
}
});
主托管活动收到回调并显示如下：
@Override
public void onSelectionClicked(Selection selection) {
if (isSignedInUser) {
selectionsToEdit.put(selection.hashCode(), selection);
if (baseCategory != null) {
selection.setCategory(baseCategory);
}
RankingSelectionEditDialogFragment rankingSelectionEditDialogFragment =
RankingSelectionEditDialogFragment.newInstance(SELECTION_EDIT, selection.hashCode(), selection);
rankingSelectionEditDialogFragment.show(getSupportFragmentManager(), EDIT_TAG);
}
else {
Intent i = new Intent(this, BusinessActivity.class);
i.putExtra(Constants.BUSINESS, selection.getBusiness().getId());
startActivity(i);
}
}
这些是我的生命周期回调：
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
selectionToEdit = savedInstanceState.getParcelable(SELECTION_TO_EDIT);
imagePath = savedInstanceState.getString(IMAGE_PATH);
}
else {
selectionToEdit = getArguments().getParcelable(SELECTION_TO_EDIT);
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
if (savedInstanceState != null) {
Log.i(TAG, "CREATED A SECOND TIME!");
}
else {
Log.i(TAG, "CREATED ONCE!");
}
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_ranking_edit, container, false);
initializeViewComponents(rootView);
return rootView;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setupFragment(selectionToEdit);
}
@Override
public void onResume() {
super.onResume();
Log.i(TAG, "onResume");
Dialog dialog = getDialog();
if (dialog != null) { // Only do this if returning a dialog, not a fragment
Log.i(TAG, "Dialog is not null");
SharedPreferences sharedPreferences
= getActivity().getSharedPreferences(Constants.PREFS, Context.MODE_PRIVATE);
// Get items required to put dialog just under the ActionBar.
int screenWidth = sharedPreferences.getInt(Constants.SCREEN_WIDTH, 720);
int screenHeight = sharedPreferences.getInt(Constants.SCREEN_HEIGHT, 1280);
int screenDPI = sharedPreferences.getInt(Constants.SCREEN_DPI, 320);
Window window = dialog.getWindow();
window.setLayout(screenWidth, WindowManager.LayoutParams.WRAP_CONTENT);
WindowManager.LayoutParams windowLayoutParams = window.getAttributes();
window.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
windowLayoutParams.y = -((screenHeight / 2) - 56) * (screenDPI / 160);
window.setAttributes(windowLayoutParams);
if (dialog.isShowing()) {
Log.i(TAG, "Dialog is showing");
}
else {
Log.i(TAG, "Dialog is not showing");
}
}
else {
Log.i(TAG, "Dialog is null");
}
Log.i(TAG, "onResume finished");
}
/**
* The system calls this only when creating the layout in a dialog.
*/
@Override
@NonNull
public Dialog onCreateDialog(Bundle savedInstanceState) {
Dialog dialog = super.onCreateDialog(savedInstanceState);
// The only reason you might override this method when using onCreateView() is
// to modify any dialog characteristics. For example, the dialog includes a
// title by default, but your custom layout might not need it. So here you can
// remove the dialog title, but you must call the superclass to get the Dialog.
SharedPreferences sharedPreferences
= getActivity().getSharedPreferences(Constants.PREFS, Context.MODE_PRIVATE);
// Get items required to put dialog just under the ActionBar.
int screenWidth = sharedPreferences.getInt(Constants.SCREEN_WIDTH, 720);
int screenHeight = sharedPreferences.getInt(Constants.SCREEN_HEIGHT, 1280);
int screenDPI = sharedPreferences.getInt(Constants.SCREEN_DPI, 320);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
Window window = dialog.getWindow();
window.setLayout(screenWidth, WindowManager.LayoutParams.WRAP_CONTENT);
WindowManager.LayoutParams windowLayoutParams = window.getAttributes();
window.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
windowLayoutParams.y = -((screenHeight / 2) - 56) * (screenDPI / 160);
windowLayoutParams.flags &= ~WindowManager.LayoutParams.FLAG_DIM_BEHIND;
window.setAttributes(windowLayoutParams);
return dialog;
}
/**
* Restore the previous currentFragment before the dialog was brought up
*/
@Override
public void dismiss() { // Used when the user deliberately dismisses the dialog
Log.i(TAG, "Dismissed");
super.dismiss(); // Ensure Super class method is called
}
/**
* Restore the previous currentFragment before the dialog was brought up
*/
@Override
public void onCancel(DialogInterface dialog) { // Used when the user inadvertently leaves the dialog,
// e.g back pressed or touched outside the dialog
Log.i(TAG, "Cancelled");
super.onCancel(dialog); // Ensure Super class method is called
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putParcelable(SELECTION_TO_EDIT, selectionToEdit);
outState.putString(IMAGE_PATH, imagePath);
}
@Override
public void onPause() {
Log.i(TAG, "onPause");
super.onPause();
}
@Override
public void onStop() {
Log.i(TAG, "onStop");
super.onStop();
}
@Override
public void onDestroyView() {
Log.i(TAG, "View Destroyed");
super.onDestroyView();
}
@Override
public void onDestroy() {
Log.i(TAG, "onDestroy");
super.onDestroy();
}
@Override
public void onDetach() {
Log.i(TAG, "onDetach");
super.onDetach();
}
编辑：我已经解决了这个问题。要显示 DialogFragment，我应该使用托管片段的 ChildFragmentManager 而不是活动。也就是说，改变这个：
RankingSelectionEditDialogFragment rankingSelectionEditDialogFragment =
RankingSelectionEditDialogFragment.newInstance(SELECTION_EDIT, selection.hashCode(), selection);
rankingSelectionEditDialogFragment.show(getSupportFragmentManager(), EDIT_TAG);
对此：
RankingSelectionEditDialogFragment rankingSelectionEditDialogFragment =
RankingSelectionEditDialogFragment.newInstance(SELECTION_EDIT, selection.hashCode(), selection);
switch (currentFragment) {
case CATEGORY_PICK:
rankingCategoryPickFragment = (RankingCategoryPickFragment)
getSupportFragmentManager().findFragmentByTag(CATEGORY_PICK_TAG);
if(rankingCategoryPickFragment != null) {
rankingSelectionEditDialogFragment.show
(rankingCategoryPickFragment.getChildFragmentManager(), EDIT_TAG);
}
break;
case BUSINESS_SORT:
rankingBusinessSortParentFragment = (RankingBusinessSortParentFragment)
getSupportFragmentManager().findFragmentByTag(BUSINESS_SORT_TAG);
if(rankingBusinessSortParentFragment != null) {
rankingSelectionEditDialogFragment.show
(rankingBusinessSortParentFragment.getChildFragmentManager(), EDIT_TAG);
}
break;
是票。希望能帮助其他有类似问题的人。