Implementations should override this class and implement * {@link #onViewCreated(View, Bundle)} to supply the * content of the dialog. Alternatively, they can override * {@link #onCreateDialog(Bundle)} to create an entirely custom dialog, such * as an AlertDialog, with its own content. * *
Topics covered here: *
* * *DialogFragment does various things to keep the fragment's lifecycle * driving it, instead of the Dialog. Note that dialogs are generally * autonomous entities -- they are their own window, receiving their own * input events, and often deciding on their own when to disappear (by * receiving a back key event or the user clicking on a button). * *
DialogFragment needs to ensure that what is happening with the Fragment * and Dialog states remains consistent. To do this, it watches for dismiss * events from the dialog and takes care of removing its own state when they * happen. This means you should use {@link #show(FragmentManager, String)}, * {@link #show(FragmentTransaction, String)}, or {@link #showNow(FragmentManager, String)} * to add an instance of DialogFragment to your UI, as these keep track of * how DialogFragment should remove itself when the dialog is dismissed. * * *
The simplest use of DialogFragment is as a floating container for the * fragment's view hierarchy. A simple implementation may look like this: * *
{@code
* public class MyDialogFragment extends DialogFragment {
* int mNum;
*
* // Create a new instance of MyDialogFragment, providing "num" as an argument.
* static MyDialogFragment newInstance(int num) {
* MyDialogFragment f = new MyDialogFragment();
*
* // Supply num input as an argument.
* Bundle args = new Bundle();
* args.putInt("num", num);
* f.setArguments(args);
*
* return f;
* }
*
* {@literal @}Override
* public void onCreate(Bundle savedInstanceState) {
* super.onCreate(savedInstanceState);
* mNum = getArguments().getInt("num");
*
* // Pick a style based on the num.
* int style = DialogFragment.STYLE_NORMAL, theme = 0;
* switch ((mNum-1)%6) {
* case 1: style = DialogFragment.STYLE_NO_TITLE; break;
* case 2: style = DialogFragment.STYLE_NO_FRAME; break;
* case 3: style = DialogFragment.STYLE_NO_INPUT; break;
* case 4: style = DialogFragment.STYLE_NORMAL; break;
* case 5: style = DialogFragment.STYLE_NORMAL; break;
* case 6: style = DialogFragment.STYLE_NO_TITLE; break;
* case 7: style = DialogFragment.STYLE_NO_FRAME; break;
* case 8: style = DialogFragment.STYLE_NORMAL; break;
* }
* switch ((mNum-1)%6) {
* case 4: theme = android.R.style.Theme_Holo; break;
* case 5: theme = android.R.style.Theme_Holo_Light_Dialog; break;
* case 6: theme = android.R.style.Theme_Holo_Light; break;
* case 7: theme = android.R.style.Theme_Holo_Light_Panel; break;
* case 8: theme = android.R.style.Theme_Holo_Light; break;
* }
* setStyle(style, theme);
* }
*
* {@literal @}Override
* public View onCreateView(LayoutInflater inflater, ViewGroup container,
* Bundle savedInstanceState) {
* return inflater.inflate(R.layout.fragment_dialog, container, false);
* }
*
* {@literal @}Override
* public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
* super.onViewCreated(view, savedInstanceState);
*
* // set DialogFragment title
* getDialog().setTitle("Dialog #" + mNum);
* }
* }
* }
*
* An example showDialog() method on the Activity could be: * *
{@code
* public void showDialog() {
* mStackLevel++;
*
* // DialogFragment.show() will take care of adding the fragment
* // in a transaction. We also want to remove any currently showing
* // dialog, so make our own transaction and take care of that here.
* FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
* Fragment prev = getSupportFragmentManager().findFragmentByTag("dialog");
* if (prev != null) {
* ft.remove(prev);
* }
* ft.addToBackStack(null);
*
* // Create and show the dialog.
* DialogFragment newFragment = MyDialogFragment.newInstance(mStackLevel);
* newFragment.show(ft, "dialog");
* }
* }
*
* This removes any currently shown dialog, creates a new DialogFragment * with an argument, and shows it as a new state on the back stack. When the * transaction is popped, the current DialogFragment and its Dialog will be * destroyed, and the previous one (if any) re-shown. Note that in this case * DialogFragment will take care of popping the transaction of the Dialog that * is dismissed separately from it. * * *
Instead of (or in addition to) implementing {@link #onViewCreated(View, Bundle)} to * generate the view hierarchy inside of a dialog, you may implement * {@link #onCreateDialog(Bundle)} to create your own custom Dialog object. * *
This is most useful for creating an AlertDialog, allowing you * to display standard alerts to the user that are managed by a fragment. * A simple example implementation of this is: * *
{@code
* public static class MyAlertDialogFragment extends DialogFragment {
*
* public static MyAlertDialogFragment newInstance(int title) {
* MyAlertDialogFragment frag = new MyAlertDialogFragment();
* Bundle args = new Bundle();
* args.putInt("title", title);
* frag.setArguments(args);
* return frag;
* }
*
* {@literal @}Override
* public Dialog onCreateDialog(@Nullable Bundle savedInstanceState) {
*
* return new AlertDialog.Builder(getActivity())
* .setIcon(R.drawable.alert_dialog_icon)
* .setTitle(title)
* .setPositiveButton(R.string.alert_dialog_ok,
* (dialogInterface, i) -> ((MainActivity)getActivity()).doPositiveClick())
* .setNegativeButton(R.string.alert_dialog_cancel,
* (dialogInterface, i) -> ((MainActivity)getActivity()).doNegativeClick())
* .create();
* return super.onCreateDialog(savedInstanceState);
* }
* }
* }
*
* The activity creating this fragment may have the following methods to * show the dialog and receive results from it: * *
{@code
* void showDialog() {
* DialogFragment newFragment = MyAlertDialogFragment.newInstance(
* R.string.alert_dialog_two_buttons_title);
* newFragment.show(getSupportFragmentManager(), "dialog");
* }
*
* public void doPositiveClick() {
* // Do stuff here.
* Log.i("MainActivity", "Positive click!");
* }
*
* public void doNegativeClick() {
* // Do stuff here.
* Log.i("MainActivity", "Negative click!");
* }
* }
*
* Note that in this case the fragment is not placed on the back stack, it * is just added as an indefinitely running fragment. Because dialogs normally * are modal, this will still operate as a back stack, since the dialog will * capture user input until it is dismissed. When it is dismissed, DialogFragment * will take care of removing itself from its fragment manager. * * *
A DialogFragment can still optionally be used as a normal fragment, if * desired. This is useful if you have a fragment that in some cases should * be shown as a dialog and others embedded in a larger UI. This behavior * will normally be automatically selected for you based on how you are using * the fragment, but can be customized with {@link #setShowsDialog(boolean)}. * *
For example, here is a simple dialog fragment: * *
{@code
* public static class MyDialogFragment extends DialogFragment {
* static MyDialogFragment newInstance() {
* return new MyDialogFragment();
* }
*
* {@literal @}Override
* public void onCreate(Bundle savedInstanceState) {
* super.onCreate(savedInstanceState);
*
* // this fragment will be displayed in a dialog
* setShowsDialog(true);
* }
*
* {@literal @}Override
* public View onCreateView(LayoutInflater inflater, ViewGroup container,
* Bundle savedInstanceState) {
* View v = inflater.inflate(R.layout.hello_world, container, false);
* View tv = v.findViewById(R.id.text);
* ((TextView)tv).setText("This is an instance of MyDialogFragment");
* return v;
* }
* }
* }
*
* An instance of this fragment can be created and shown as a dialog: * *
{@code
* void showDialog() {
* // Create the fragment and show it as a dialog.
* DialogFragment newFragment = MyDialogFragment.newInstance();
* newFragment.show(getSupportFragmentManager(), "dialog");
* }
* }
*
* It can also be added as content in a view hierarchy: * *
{@code
* FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
* DialogFragment newFragment = MyDialogFragment.newInstance();
* ft.add(R.id.embedded, newFragment);
* ft.commit();
* }
*/
public class DialogFragment extends Fragment
implements DialogInterface.OnCancelListener, DialogInterface.OnDismissListener {
/** @hide */
@RestrictTo(LIBRARY_GROUP_PREFIX)
@IntDef({STYLE_NORMAL, STYLE_NO_TITLE, STYLE_NO_FRAME, STYLE_NO_INPUT})
@Retention(RetentionPolicy.SOURCE)
private @interface DialogStyle {}
/**
* Style for {@link #setStyle(int, int)}: a basic,
* normal dialog.
*/
public static final int STYLE_NORMAL = 0;
/**
* Style for {@link #setStyle(int, int)}: don't include
* a title area.
*/
public static final int STYLE_NO_TITLE = 1;
/**
* Style for {@link #setStyle(int, int)}: don't draw
* any frame at all; the view hierarchy returned by {@link #onCreateView}
* is entirely responsible for drawing the dialog.
*/
public static final int STYLE_NO_FRAME = 2;
/**
* Style for {@link #setStyle(int, int)}: like
* {@link #STYLE_NO_FRAME}, but also disables all input to the dialog.
* The user can not touch it, and its window will not receive input focus.
*/
public static final int STYLE_NO_INPUT = 3;
private static final String SAVED_DIALOG_STATE_TAG = "android:savedDialogState";
private static final String SAVED_STYLE = "android:style";
private static final String SAVED_THEME = "android:theme";
private static final String SAVED_CANCELABLE = "android:cancelable";
private static final String SAVED_SHOWS_DIALOG = "android:showsDialog";
private static final String SAVED_BACK_STACK_ID = "android:backStackId";
/**
* Copied from {@link Dialog}.
*/
private static final String SAVED_INTERNAL_DIALOG_SHOWING = "android:dialogShowing";
private Handler mHandler;
private Runnable mDismissRunnable = new Runnable() {
@SuppressLint("SyntheticAccessor")
@Override
public void run() {
mOnDismissListener.onDismiss(mDialog);
}
};
private DialogInterface.OnCancelListener mOnCancelListener =
new DialogInterface.OnCancelListener() {
@SuppressLint("SyntheticAccessor")
@Override
public void onCancel(@Nullable DialogInterface dialog) {
if (mDialog != null) {
DialogFragment.this.onCancel(mDialog);
}
}
};
private DialogInterface.OnDismissListener mOnDismissListener =
new DialogInterface.OnDismissListener() {
@SuppressLint("SyntheticAccessor")
@Override
public void onDismiss(@Nullable DialogInterface dialog) {
if (mDialog != null) {
DialogFragment.this.onDismiss(mDialog);
}
}
};
private int mStyle = STYLE_NORMAL;
private int mTheme = 0;
private boolean mCancelable = true;
private boolean mShowsDialog = true;
private int mBackStackId = -1;
private boolean mCreatingDialog;
private ObserverIt is strongly recommended to supply arguments with {@link #setArguments} * and later retrieved by the Fragment with {@link #getArguments}. These arguments * are automatically saved and restored alongside the Fragment. * *
Applications should generally not implement a constructor. Prefer * {@link #onAttach(Context)} instead. It is the first place application code can run where * the fragment is ready to be used - the point where the fragment is actually associated with * its context. */ public DialogFragment() { super(); } /** * Alternate constructor that can be called from your default, no argument constructor to * provide a default layout that will be inflated by * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. * *
* class MyDialogFragment extends DialogFragment {
* public MyDialogFragment() {
* super(R.layout.dialog_fragment_main);
* }
* }
*
*
* You must
* {@link FragmentManager#setFragmentFactory(FragmentFactory) set a custom FragmentFactory}
* if you want to use a non-default constructor to ensure that your constructor is called
* when the fragment is re-instantiated.
*
* @see #DialogFragment()
* @see #onCreateView(LayoutInflater, ViewGroup, Bundle)
*/
public DialogFragment(@LayoutRes int contentLayoutId) {
super(contentLayoutId);
}
/**
* Call to customize the basic appearance and behavior of the
* fragment's dialog. This can be used for some common dialog behaviors,
* taking care of selecting flags, theme, and other options for you. The
* same effect can be achieve by manually setting Dialog and Window
* attributes yourself. Calling this after the fragment's Dialog is
* created will have no effect.
*
* @param style Selects a standard style: may be {@link #STYLE_NORMAL},
* {@link #STYLE_NO_TITLE}, {@link #STYLE_NO_FRAME}, or
* {@link #STYLE_NO_INPUT}.
* @param theme Optional custom theme. If 0, an appropriate theme (based
* on the style) will be selected for you.
*/
public void setStyle(@DialogStyle int style, @StyleRes int theme) {
if (FragmentManager.isLoggingEnabled(Log.VERBOSE)) {
Log.d(TAG, "Setting style and theme for DialogFragment " + this + " to " + style
+ ", " + theme);
}
mStyle = style;
if (mStyle == STYLE_NO_FRAME || mStyle == STYLE_NO_INPUT) {
mTheme = android.R.style.Theme_Panel;
}
if (theme != 0) {
mTheme = theme;
}
}
/**
* Display the dialog, adding the fragment to the given FragmentManager. This
* is a convenience for explicitly creating a transaction, adding the
* fragment to it with the given tag, and {@link FragmentTransaction#commit() committing} it.
* This does not add the transaction to the fragment back stack. When the fragment
* is dismissed, a new transaction will be executed to remove it from
* the activity.
* @param manager The FragmentManager this fragment will be added to.
* @param tag The tag for this fragment, as per
* {@link FragmentTransaction#add(Fragment, String) FragmentTransaction.add}.
*/
public void show(@NonNull FragmentManager manager, @Nullable String tag) {
mDismissed = false;
mShownByMe = true;
FragmentTransaction ft = manager.beginTransaction();
ft.setReorderingAllowed(true);
ft.add(this, tag);
ft.commit();
}
/**
* Display the dialog, adding the fragment using an existing transaction
* and then {@link FragmentTransaction#commit() committing} the transaction.
* @param transaction An existing transaction in which to add the fragment.
* @param tag The tag for this fragment, as per
* {@link FragmentTransaction#add(Fragment, String) FragmentTransaction.add}.
* @return Returns the identifier of the committed transaction, as per
* {@link FragmentTransaction#commit() FragmentTransaction.commit()}.
*/
public int show(@NonNull FragmentTransaction transaction, @Nullable String tag) {
mDismissed = false;
mShownByMe = true;
transaction.add(this, tag);
mViewDestroyed = false;
mBackStackId = transaction.commit();
return mBackStackId;
}
/**
* Display the dialog, immediately adding the fragment to the given FragmentManager. This
* is a convenience for explicitly creating a transaction, adding the
* fragment to it with the given tag, and calling {@link FragmentTransaction#commitNow()}.
* This does not add the transaction to the fragment back stack. When the fragment
* is dismissed, a new transaction will be executed to remove it from
* the activity.
* @param manager The FragmentManager this fragment will be added to.
* @param tag The tag for this fragment, as per
* {@link FragmentTransaction#add(Fragment, String) FragmentTransaction.add}.
*/
public void showNow(@NonNull FragmentManager manager, @Nullable String tag) {
mDismissed = false;
mShownByMe = true;
FragmentTransaction ft = manager.beginTransaction();
ft.setReorderingAllowed(true);
ft.add(this, tag);
ft.commitNow();
}
/**
* Dismiss the fragment and its dialog. If the fragment was added to the
* back stack, all back stack state up to and including this entry will
* be popped. Otherwise, a new transaction will be committed to remove
* the fragment.
*/
public void dismiss() {
dismissInternal(false, false, false);
}
/**
* Version of {@link #dismiss()} that uses {@link FragmentTransaction#commitNow()}.
* See linked documentation for further details.
*/
@MainThread
public void dismissNow() {
dismissInternal(false, false, true);
}
/**
* Version of {@link #dismiss()} that uses
* {@link FragmentTransaction#commitAllowingStateLoss()
* FragmentTransaction.commitAllowingStateLoss()}. See linked
* documentation for further details.
*/
public void dismissAllowingStateLoss() {
dismissInternal(true, false, false);
}
private void dismissInternal(boolean allowStateLoss, boolean fromOnDismiss, boolean immediate) {
if (mDismissed) {
return;
}
mDismissed = true;
mShownByMe = false;
if (mDialog != null) {
// Instead of waiting for a posted onDismiss(), null out
// the listener and call onDismiss() manually to ensure
// that the callback happens before onDestroy()
mDialog.setOnDismissListener(null);
mDialog.dismiss();
if (!fromOnDismiss) {
// onDismiss() is always called on the main thread, so
// we mimic that behavior here. The difference here is that
// we don't post the message to ensure that the onDismiss()
// callback still happens before onDestroy()
if (Looper.myLooper() == mHandler.getLooper()) {
onDismiss(mDialog);
} else {
mHandler.post(mDismissRunnable);
}
}
}
mViewDestroyed = true;
if (mBackStackId >= 0) {
if (immediate) {
getParentFragmentManager().popBackStackImmediate(mBackStackId,
FragmentManager.POP_BACK_STACK_INCLUSIVE);
} else {
getParentFragmentManager().popBackStack(mBackStackId,
FragmentManager.POP_BACK_STACK_INCLUSIVE, allowStateLoss);
}
mBackStackId = -1;
} else {
FragmentTransaction ft = getParentFragmentManager().beginTransaction();
ft.setReorderingAllowed(true);
ft.remove(this);
// allowStateLoss and immediate should not both be true
if (immediate) {
ft.commitNow();
} else if (allowStateLoss) {
ft.commitAllowingStateLoss();
} else {
ft.commit();
}
}
}
/**
* Return the {@link Dialog} this fragment is currently controlling.
*
* @see #requireDialog()
*/
@Nullable
public Dialog getDialog() {
return mDialog;
}
/**
* Return the {@link Dialog} this fragment is currently controlling.
*
* @throws IllegalStateException if the Dialog has not yet been created (before
* {@link #onCreateDialog(Bundle)}) or has been destroyed (after {@link #onDestroyView()}.
* @see #getDialog()
*/
@NonNull
public final Dialog requireDialog() {
Dialog dialog = getDialog();
if (dialog == null) {
throw new IllegalStateException("DialogFragment " + this + " does not have a Dialog.");
}
return dialog;
}
@StyleRes
public int getTheme() {
return mTheme;
}
/**
* Control whether the shown Dialog is cancelable. Use this instead of
* directly calling {@link Dialog#setCancelable(boolean)
* Dialog.setCancelable(boolean)}, because DialogFragment needs to change
* its behavior based on this.
*
* @param cancelable If true, the dialog is cancelable. The default
* is true.
*/
public void setCancelable(boolean cancelable) {
mCancelable = cancelable;
if (mDialog != null) mDialog.setCancelable(cancelable);
}
/**
* Return the current value of {@link #setCancelable(boolean)}.
*/
public boolean isCancelable() {
return mCancelable;
}
/**
* Controls whether this fragment should be shown in a dialog. If not
* set, no Dialog will be created and the fragment's view hierarchy will
* thus not be added to it. This allows you to instead use it as a
* normal fragment (embedded inside of its activity).
*
* This is normally set for you based on whether the fragment is * associated with a container view ID passed to * {@link FragmentTransaction#add(int, Fragment) FragmentTransaction.add(int, Fragment)}. * If the fragment was added with a container, setShowsDialog will be * initialized to false; otherwise, it will be true. * *
If calling this manually, it should be called in {@link #onCreate(Bundle)} * as calling it any later will have no effect. * * @param showsDialog If true, the fragment will be displayed in a Dialog. * If false, no Dialog will be created and the fragment's view hierarchy * left undisturbed. */ public void setShowsDialog(boolean showsDialog) { mShowsDialog = showsDialog; } /** * Return the current value of {@link #setShowsDialog(boolean)}. */ public boolean getShowsDialog() { return mShowsDialog; } @MainThread @Override public void onAttach(@NonNull Context context) { super.onAttach(context); getViewLifecycleOwnerLiveData().observeForever(mObserver); if (!mShownByMe) { // If not explicitly shown through our API, take this as an // indication that the dialog is no longer dismissed. mDismissed = false; } } @MainThread @Override public void onDetach() { super.onDetach(); if (!mShownByMe && !mDismissed) { // The fragment was not shown by a direct call here, it is not // dismissed, and now it is being detached... well, okay, thou // art now dismissed. Have fun. mDismissed = true; } getViewLifecycleOwnerLiveData().removeObserver(mObserver); } @MainThread @Override @SuppressWarnings("deprecation") public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); // This assumes that onCreate() is being called on the main thread mHandler = new Handler(); mShowsDialog = mContainerId == 0; if (savedInstanceState != null) { mStyle = savedInstanceState.getInt(SAVED_STYLE, STYLE_NORMAL); mTheme = savedInstanceState.getInt(SAVED_THEME, 0); mCancelable = savedInstanceState.getBoolean(SAVED_CANCELABLE, true); mShowsDialog = savedInstanceState.getBoolean(SAVED_SHOWS_DIALOG, mShowsDialog); mBackStackId = savedInstanceState.getInt(SAVED_BACK_STACK_ID, -1); } } @Override void performCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { super.performCreateView(inflater, container, savedInstanceState); // If no view was set, we need to call onRestoreInstance on the dialog to ensure // the state is restored. if (mView == null) { if (mDialog != null && savedInstanceState != null) { Bundle dialogState = savedInstanceState.getBundle(SAVED_DIALOG_STATE_TAG); if (dialogState != null) { mDialog.onRestoreInstanceState(dialogState); } } } } @NonNull @Override FragmentContainer createFragmentContainer() { final FragmentContainer fragmentContainer = super.createFragmentContainer(); return new FragmentContainer() { @Nullable @Override public View onFindViewById(int id) { if (fragmentContainer.onHasView()) { return fragmentContainer.onFindViewById(id); } return DialogFragment.this.onFindViewById(id); } @Override public boolean onHasView() { return fragmentContainer.onHasView() || DialogFragment.this.onHasView(); } }; } @Nullable View onFindViewById(int id) { if (mDialog != null) { return mDialog.findViewById(id); } return null; } boolean onHasView() { return mDialogCreated; } /** * {@inheritDoc} * *
* If this is called from within {@link #onCreateDialog(Bundle)}, the layout inflater from * {@link Fragment#onGetLayoutInflater(Bundle)}, without the dialog theme, will be returned. */ @Override @NonNull public LayoutInflater onGetLayoutInflater(@Nullable Bundle savedInstanceState) { LayoutInflater layoutInflater = super.onGetLayoutInflater(savedInstanceState); if (!mShowsDialog || mCreatingDialog) { if (FragmentManager.isLoggingEnabled(Log.VERBOSE)) { String message = "getting layout inflater for DialogFragment " + this; if (!mShowsDialog) { Log.d(TAG, "mShowsDialog = false: " + message); } else { Log.d(TAG, "mCreatingDialog = true: " + message); } } return layoutInflater; } prepareDialog(savedInstanceState); if (FragmentManager.isLoggingEnabled(Log.VERBOSE)) { Log.d(TAG, "get layout inflater for DialogFragment " + this + " from dialog context"); } if (mDialog != null) { layoutInflater = layoutInflater.cloneInContext(mDialog.getContext()); } return layoutInflater; } /** @hide */ @RestrictTo(LIBRARY_GROUP_PREFIX) public void setupDialog(@NonNull Dialog dialog, int style) { switch (style) { case STYLE_NO_INPUT: Window window = dialog.getWindow(); if (window != null) { window.addFlags(WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE); } // fall through... case STYLE_NO_FRAME: case STYLE_NO_TITLE: dialog.requestWindowFeature(Window.FEATURE_NO_TITLE); } } /** * Override to build your own custom Dialog container. This is typically * used to show an AlertDialog instead of a generic Dialog; when doing so, * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} does not need * to be implemented since the AlertDialog takes care of its own content. * *
This method will be called after {@link #onCreate(Bundle)} and * immediately before {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. The * default implementation simply instantiates and returns a {@link Dialog} * class. * *
Note: DialogFragment own the {@link Dialog#setOnCancelListener * Dialog.setOnCancelListener} and {@link Dialog#setOnDismissListener * Dialog.setOnDismissListener} callbacks. You must not set them yourself. * To find out about these events, override {@link #onCancel(DialogInterface)} * and {@link #onDismiss(DialogInterface)}.
* * @param savedInstanceState The last saved instance state of the Fragment, * or null if this is a freshly created Fragment. * * @return Return a new Dialog instance to be displayed by the Fragment. */ @MainThread @NonNull public Dialog onCreateDialog(@Nullable Bundle savedInstanceState) { if (FragmentManager.isLoggingEnabled(Log.DEBUG)) { Log.d(TAG, "onCreateDialog called for DialogFragment " + this); } return new ComponentDialog(requireContext(), getTheme()); } @Override public void onCancel(@NonNull DialogInterface dialog) { } @CallSuper @Override public void onDismiss(@NonNull DialogInterface dialog) { if (!mViewDestroyed) { // Note: we need to use allowStateLoss, because the dialog // dispatches this asynchronously so we can receive the call // after the activity is paused. Worst case, when the user comes // back to the activity they see the dialog again. if (FragmentManager.isLoggingEnabled(Log.DEBUG)) { Log.d(TAG, "onDismiss called for DialogFragment " + this); } dismissInternal(true, true, false); } } private void prepareDialog(@Nullable Bundle savedInstanceState) { if (!mShowsDialog) { return; } if (!mDialogCreated) { try { mCreatingDialog = true; mDialog = onCreateDialog(savedInstanceState); // mShowsDialog might have changed in onCreateDialog, so we should only proceed // with setting up the dialog if mShowsDialog is still true if (mShowsDialog) { setupDialog(mDialog, mStyle); final Context context = getContext(); if (context instanceof Activity) { mDialog.setOwnerActivity((Activity) context); } mDialog.setCancelable(mCancelable); mDialog.setOnCancelListener(mOnCancelListener); mDialog.setOnDismissListener(mOnDismissListener); mDialogCreated = true; } else { // Ensure that when mShowsDialog is set to false in onCreateDialog // that getDialog() returns null mDialog = null; } } finally { mCreatingDialog = false; } } } @MainThread @Override public void onViewStateRestored(@Nullable Bundle savedInstanceState) { super.onViewStateRestored(savedInstanceState); if (mDialog != null && savedInstanceState != null) { Bundle dialogState = savedInstanceState.getBundle(SAVED_DIALOG_STATE_TAG); if (dialogState != null) { mDialog.onRestoreInstanceState(dialogState); } } } /** * {@inheritDoc} * * @deprecated use {@link #onCreateDialog} for code touching the dialog created by * {@link #onCreateDialog}, {@link #onViewCreated(View, Bundle)} for code touching the * view created by {@link #onCreateView} and {@link #onCreate(Bundle)} for other initialization. * To get a callback specifically when a Fragment activity's * {@link Activity#onCreate(Bundle)} is called, register a * {@link androidx.lifecycle.LifecycleObserver} on the Activity's * {@link Lifecycle} in {@link #onAttach(Context)}, removing it when it receives the * {@link Lifecycle.State#CREATED} callback. */ @SuppressWarnings("deprecation") @MainThread @Override @Deprecated public void onActivityCreated(@Nullable Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); } @MainThread @Override public void onStart() { super.onStart(); if (mDialog != null) { mViewDestroyed = false; mDialog.show(); // Only after we show does the dialog window actually return a decor view. View decorView = mDialog.getWindow().getDecorView(); ViewTreeLifecycleOwner.set(decorView, this); ViewTreeViewModelStoreOwner.set(decorView, this); ViewTreeSavedStateRegistryOwner.set(decorView, this); } } @MainThread @Override public void onSaveInstanceState(@NonNull Bundle outState) { super.onSaveInstanceState(outState); if (mDialog != null) { Bundle dialogState = mDialog.onSaveInstanceState(); dialogState.putBoolean(SAVED_INTERNAL_DIALOG_SHOWING, false); outState.putBundle(SAVED_DIALOG_STATE_TAG, dialogState); } if (mStyle != STYLE_NORMAL) { outState.putInt(SAVED_STYLE, mStyle); } if (mTheme != 0) { outState.putInt(SAVED_THEME, mTheme); } if (!mCancelable) { outState.putBoolean(SAVED_CANCELABLE, mCancelable); } if (!mShowsDialog) { outState.putBoolean(SAVED_SHOWS_DIALOG, mShowsDialog); } if (mBackStackId != -1) { outState.putInt(SAVED_BACK_STACK_ID, mBackStackId); } } @MainThread @Override public void onStop() { super.onStop(); if (mDialog != null) { mDialog.hide(); } } /** * Remove dialog. */ @MainThread @Override public void onDestroyView() { super.onDestroyView(); if (mDialog != null) { // Set removed here because this dismissal is just to hide // the dialog -- we don't want this to cause the fragment to // actually be removed. mViewDestroyed = true; // Instead of waiting for a posted onDismiss(), null out // the listener and call onDismiss() manually to ensure // that the callback happens before onDestroy() mDialog.setOnDismissListener(null); mDialog.dismiss(); if (!mDismissed) { // Don't send a second onDismiss() callback if we've already // dismissed the dialog manually in dismissInternal() onDismiss(mDialog); } mDialog = null; mDialogCreated = false; } } }