Fragment

public Fragment()

Constructor used by the default FragmentFactory. You must 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.

It is strongly recommended to supply arguments with setArguments and later retrieved by the Fragment with getArguments. These arguments are automatically saved and restored alongside the Fragment.

Applications should generally not implement a constructor. Prefer onAttach 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. Some applications may also want to implement onInflate to retrieve attributes from a layout resource, although note this happens when the fragment is attached.

@ContentView
public Fragment(@LayoutRes int contentLayoutId)

Alternate constructor that can be called from your default, no argument constructor to provide a default layout that will be inflated by onCreateView.

class MyFragment extends Fragment {
  public MyFragment() {
    super(R.layout.fragment_main);
  }
}

public void addOnContextAvailableListener(
    @NonNull OnContextAvailableListener listener
)

Add a new OnContextAvailableListener for receiving a callback for when this class is associated with a android.content.Context.

Listeners are triggered in the order they are added when added before the Context is available. Listeners added after the context has been made available will have the Context synchronously delivered to them as part of this call.

public void dump(
    @NonNull String prefix,
    @Nullable FileDescriptor fd,
    @NonNull PrintWriter writer,
    @Nullable String[] args
)

Print the Fragments's state into the given stream.

public final boolean equals(@Nullable Object o)

Subclasses can not override equals().

public final @Nullable FragmentActivity getActivity()

Return the FragmentActivity this fragment is currently associated with. May return null if the fragment is associated with a Context instead.

public boolean getAllowEnterTransitionOverlap()

Returns whether the the exit transition and enter transition overlap or not. When true, the enter transition will start as soon as possible. When false, the enter transition will wait until the exit transition completes before starting.

public boolean getAllowReturnTransitionOverlap()

Returns whether the the return transition and reenter transition overlap or not. When true, the reenter transition will start as soon as possible. When false, the reenter transition will wait until the return transition completes before starting.

public final @Nullable Bundle getArguments()

Return the arguments supplied when the fragment was instantiated, if any.

public final @NonNull FragmentManager getChildFragmentManager()

Return a private FragmentManager for placing and managing Fragments inside of this Fragment.

public @Nullable Context getContext()

Return the Context this fragment is currently associated with.

@CallSuper
public @NonNull CreationExtras getDefaultViewModelCreationExtras()

Returns the default CreationExtras that should be passed into ViewModelProvider.Factory.create when no overriding CreationExtras were passed to the ViewModelProvider constructors.

The Fragment's arguments when this is first called will be used as the defaults to any androidx.lifecycle.SavedStateHandle passed to a view model created using this extra.

public @NonNull ViewModelProvider.Factory getDefaultViewModelProviderFactory()

Returns the default ViewModelProvider.Factory that should be used when no custom Factory is provided to the ViewModelProvider constructors.

public @Nullable Object getEnterTransition()

Returns the Transition that will be used to move Views into the initial scene. The entering Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as entering is governed by changing visibility from INVISIBLE to VISIBLE.

public @Nullable Object getExitTransition()

Returns the Transition that will be used to move Views out of the scene when the fragment is removed, hidden, or detached when not popping the back stack. The exiting Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as exiting is governed by changing visibility from VISIBLE to INVISIBLE. If transition is null, the views will remain unaffected.

public final @Nullable FragmentManager getFragmentManager()

Return the FragmentManager for interacting with fragments associated with this fragment's activity. Note that this will be non-null slightly before getActivity, during the time from when the fragment is placed in a FragmentTransaction until it is committed and attached to its activity.

If this Fragment is a child of another Fragment, the FragmentManager returned here will be the parent's getChildFragmentManager.

public final @Nullable Object getHost()

Return the host object of this fragment. May return null if the fragment isn't currently being hosted.

public final int getId()

Return the identifier this fragment is known by. This is either the android:id value supplied in a layout or the container view ID supplied when adding the fragment.

public final @NonNull LayoutInflater getLayoutInflater()

Returns the cached LayoutInflater used to inflate Views of this Fragment. If onGetLayoutInflater has not been called onGetLayoutInflater will be called with a null argument and that value will be cached.

The cached LayoutInflater will be replaced immediately prior to onCreateView and cleared immediately after onDetach.

public @NonNull Lifecycle getLifecycle()

Returns the Lifecycle of the provider.

Overriding this method is no longer supported and this method will be made final in a future version of Fragment.

public @NonNull LoaderManager getLoaderManager()

Return the LoaderManager for this fragment.

public final @Nullable Fragment getParentFragment()

Returns the parent Fragment containing this Fragment. If this Fragment is attached directly to an Activity, returns null.

public final @NonNull FragmentManager getParentFragmentManager()

Return the FragmentManager for interacting with fragments associated with this fragment's activity. Note that this will be available slightly before getActivity, during the time from when the fragment is placed in a FragmentTransaction until it is committed and attached to its activity.

If this Fragment is a child of another Fragment, the FragmentManager returned here will be the parent's getChildFragmentManager.

public @Nullable Object getReenterTransition()

Returns the Transition that will be used to move Views in to the scene when returning due to popping a back stack. The entering Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as exiting is governed by changing visibility from VISIBLE to INVISIBLE. If nothing is set, the default will be to use the same transition as getExitTransition.

public final @NonNull Resources getResources()

Return requireActivity().getResources().

public final boolean getRetainInstance()

Returns true if this fragment instance's state will be retained across configuration changes, and false if it will not.

public @Nullable Object getReturnTransition()

Returns the Transition that will be used to move Views out of the scene when the Fragment is preparing to be removed, hidden, or detached because of popping the back stack. The exiting Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as entering is governed by changing visibility from VISIBLE to INVISIBLE. If nothing is set, the default will be to use the same transition as getEnterTransition.

public final @NonNull SavedStateRegistry getSavedStateRegistry()

The SavedStateRegistry owned by this SavedStateRegistryOwner

public @Nullable Object getSharedElementEnterTransition()

Returns the Transition that will be used for shared elements transferred into the content Scene. Typical Transitions will affect size and location, such as android.transition.ChangeBounds. A null value will cause transferred shared elements to blink to the final position.

public @Nullable Object getSharedElementReturnTransition()

Return the Transition that will be used for shared elements transferred back during a pop of the back stack. This Transition acts in the leaving Fragment. Typical Transitions will affect size and location, such as android.transition.ChangeBounds. A null value will cause transferred shared elements to blink to the final position. If no value is set, the default will be to use the same value as setSharedElementEnterTransition.

public final @NonNull String getString(@StringRes int resId)

Return a localized string from the application's package's default string table.

public final @NonNull String getString(@StringRes int resId, @Nullable Object[] formatArgs)

Return a localized formatted string from the application's package's default string table, substituting the format arguments as defined in java.util.Formatter and format.

public final @Nullable String getTag()

Get the tag name of the fragment, if specified.

public final @Nullable Fragment getTargetFragment()

Return the target fragment set by setTargetFragment.

public final int getTargetRequestCode()

Return the target request code set by setTargetFragment.

public final @NonNull CharSequence getText(@StringRes int resId)

Return a localized, styled CharSequence from the application's package's default string table.

public @Nullable View getView()

Get the root view for the fragment's layout (the one returned by onCreateView), if provided.

@MainThread
public @NonNull LifecycleOwner getViewLifecycleOwner()

Get a LifecycleOwner that represents the Fragment's View lifecycle. In most cases, this mirrors the lifecycle of the Fragment itself, but in cases of detached Fragments, the lifecycle of the Fragment can be considerably longer than the lifecycle of the View itself.

Namely, the lifecycle of the Fragment's View is:

1. created after onViewStateRestored
2. started after onStart
3. resumed after onResume
4. paused before onPause
5. stopped before onStop
6. destroyed before onDestroyView

The view lifecycle remains valid through the call to onDestroyView, after which getView will return null, the view lifecycle will be destroyed, and this method will throw an IllegalStateException. Consider using getViewLifecycleOwnerLiveData or runOnCommit to receive a callback for when the Fragment's view lifecycle is available.

This should only be called on the main thread.

Overriding this method is no longer supported and this method will be made final in a future version of Fragment.

public @NonNull LiveData<LifecycleOwner> getViewLifecycleOwnerLiveData()

Retrieve a LiveData which allows you to observe the lifecycle of the Fragment's View.

This will be set to the new LifecycleOwner after onCreateView returns a non-null View and will set to null after onDestroyView.

Overriding this method is no longer supported and this method will be made final in a future version of Fragment.

public @NonNull ViewModelStore getViewModelStore()

Returns the ViewModelStore associated with this Fragment

Overriding this method is no longer supported and this method will be made final in a future version of Fragment.

public final int hashCode()

Subclasses can not override hashCode().

public static @NonNull Fragment instantiate(@NonNull Context context, @NonNull String fname)

Like instantiate but with a null argument Bundle.

public static @NonNull Fragment instantiate(
    @NonNull Context context,
    @NonNull String fname,
    @Nullable Bundle args
)

Create a new instance of a Fragment with the given class name. This is the same as calling its empty constructor, setting the ClassLoader on the supplied arguments, then calling setArguments.

public final boolean isAdded()

Return true if the fragment is currently added to its activity.

public final boolean isDetached()

Return true if the fragment has been explicitly detached from the UI. That is, FragmentTransaction.detach(Fragment) has been used on it.

public final boolean isHidden()

Return true if the fragment has been hidden. This includes the case if the fragment is hidden because its parent is hidden. By default fragments are shown. You can find out about changes to this state with onHiddenChanged. Note that the hidden state is orthogonal to other states -- that is, to be visible to the user, a fragment must be both started and not hidden.

public final boolean isInLayout()

Return true if the layout is included as part of an activity view hierarchy via the tag. This will always be true when fragments are created through the tag, except in the case where an old fragment is restored from a previous state and it does not appear in the layout of the current state.

public final boolean isRemoving()

Return true if this fragment is currently being removed from its activity. This is not whether its activity is finishing, but rather whether it is in the process of being removed from its activity.

public final boolean isResumed()

Return true if the fragment is in the resumed state. This is true for the duration of onResume and onPause as well.

public final boolean isStateSaved()

Returns true if this fragment is added and its state has already been saved by its host. Any operations that would change saved state should not be performed if this method returns true, and some operations such as setArguments will fail.

public final boolean isVisible()

Return true if the fragment is currently visible to the user. This means it: (1) has been added, (2) has its view attached to the window, and (3) is not hidden.

@MainThread
@CallSuper
public void onActivityCreated(@Nullable Bundle savedInstanceState)

Called when the fragment's activity has been created and this fragment's view hierarchy instantiated. It can be used to do final initialization once these pieces are in place, such as retrieving views or restoring state. It is also useful for fragments that use setRetainInstance to retain their instance, as this callback tells the fragment when it is fully associated with the new activity instance. This is called after onCreateView and before onViewStateRestored.

public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data)

Receive the result from a previous call to startActivityForResult. This follows the related Activity API as described there in onActivityResult.

@MainThread
@CallSuper
public void onAttach(@NonNull Activity activity)

Called when a fragment is first attached to its activity. onCreate will be called after this.

@MainThread
@CallSuper
public void onAttach(@NonNull Context context)

Called when a fragment is first attached to its context. onCreate will be called after this.

@MainThread
public void onAttachFragment(@NonNull Fragment childFragment)

Called when a fragment is attached as a child of this fragment.

This is called after the attached fragment's onAttach and before the attached fragment's onCreate if the fragment has not yet had a previous call to onCreate.

@MainThread
public boolean onContextItemSelected(@NonNull MenuItem item)

This hook is called whenever an item in a context menu is selected. The default implementation simply returns false to have the normal processing happen (calling the item's Runnable or sending a message to its Handler as appropriate). You can use this method for any items for which you would like to do processing without those other facilities.

Use getMenuInfo to get extra information set by the View that added this menu item.

Derived classes should call through to the base class for it to perform the default menu handling.

@MainThread
@CallSuper
public void onCreate(@Nullable Bundle savedInstanceState)

Called to do initial creation of a fragment. This is called after onAttach and before onCreateView.

Note that this can be called while the fragment's activity is still in the process of being created. As such, you can not rely on things like the activity's content view hierarchy being initialized at this point. If you want to do work once the activity itself is created, add a androidx.lifecycle.LifecycleObserver on the activity's Lifecycle, removing it when it receives the CREATED callback.

Any restored child fragments will be created before the base Fragment.onCreate method returns.

@MainThread
public @Nullable Animation onCreateAnimation(int transit, boolean enter, int nextAnim)

Called when a fragment loads an animation. Note that if setCustomAnimations was called with Animator resources instead of Animation resources, nextAnim will be an animator resource.

@MainThread
public @Nullable Animator onCreateAnimator(int transit, boolean enter, int nextAnim)

Called when a fragment loads an animator. This will be called when onCreateAnimation returns null. Note that if setCustomAnimations was called with Animation resources instead of Animator resources, nextAnim will be an animation resource.

@MainThread
public void onCreateContextMenu(
    @NonNull ContextMenu menu,
    @NonNull View v,
    @Nullable ContextMenu.ContextMenuInfo menuInfo
)

Called when a context menu for the view is about to be shown. Unlike onCreateOptionsMenu, this will be called every time the context menu is about to be shown and should be populated for the view (or item inside the view for AdapterView subclasses, this can be found in the menuInfo)).

Use onContextItemSelected to know when an item has been selected.

The default implementation calls up to Activity.onCreateContextMenu, though you can not call this implementation if you don't want that behavior.

It is not safe to hold onto the context menu after this method returns.

@MainThread
public void onCreateOptionsMenu(@NonNull Menu menu, @NonNull MenuInflater inflater)

Initialize the contents of the Fragment host's standard options menu. You should place your menu items in to menu. For this method to be called, you must have first called setHasOptionsMenu. See Activity.onCreateOptionsMenu for more information.

@MainThread
public @Nullable View onCreateView(
    @NonNull LayoutInflater inflater,
    @Nullable ViewGroup container,
    @Nullable Bundle savedInstanceState
)

Called to have the fragment instantiate its user interface view. This is optional, and non-graphical fragments can return null. This will be called between onCreate and onViewCreated.

A default View can be returned by calling Fragment in your constructor. Otherwise, this method returns null.

It is recommended to only inflate the layout in this method and move logic that operates on the returned View to onViewCreated.

If you return a View from here, you will later be called in onDestroyView when the view is being released.

@MainThread
@CallSuper
public void onDestroy()

Called when the fragment is no longer in use. This is called after onStop and before onDetach.

@MainThread
public void onDestroyOptionsMenu()

Called when this fragment's option menu items are no longer being included in the overall options menu. Receiving this call means that the menu needed to be rebuilt, but this fragment's items were not included in the newly built menu (its onCreateOptionsMenu was not called).

@MainThread
@CallSuper
public void onDestroyView()

Called when the view previously created by onCreateView has been detached from the fragment. The next time the fragment needs to be displayed, a new view will be created. This is called after onStop and before onDestroy. It is called regardless of whether onCreateView returned a non-null view. Internally it is called after the view's state has been saved but before it has been removed from its parent.

@MainThread
@CallSuper
public void onDetach()

Called when the fragment is no longer attached to its activity. This is called after onDestroy.

public @NonNull LayoutInflater onGetLayoutInflater(@Nullable Bundle savedInstanceState)

Returns the LayoutInflater used to inflate Views of this Fragment. The default implementation will throw an exception if the Fragment is not attached.

@MainThread
public void onHiddenChanged(boolean hidden)

Called when the hidden state (as returned by isHidden of the fragment or another fragment in its hierarchy has changed. Fragments start out not hidden; this will be called whenever the fragment changes state from that.

@UiThread
@CallSuper
public void onInflate(
    @NonNull Activity activity,
    @NonNull AttributeSet attrs,
    @Nullable Bundle savedInstanceState
)

Called when a fragment is being created as part of a view layout inflation, typically from setting the content view of an activity.

@UiThread
@CallSuper
public void onInflate(
    @NonNull Context context,
    @NonNull AttributeSet attrs,
    @Nullable Bundle savedInstanceState
)

Called when a fragment is being created as part of a view layout inflation, typically from setting the content view of an activity. This may be called immediately after the fragment is created from a FragmentContainerView in a layout file. Note this is before the fragment's onAttach has been called; all you should do here is parse the attributes and save them away.

This is called the first time the fragment is inflated. If it is being inflated into a new instance with saved state, this method will not be called a second time for the restored state fragment.

Here is a typical implementation of a fragment that can take parameters both through attributes supplied here as well from getArguments:

public static class MyFragment extends Fragment {
    CharSequence mLabel;

    /**
     * Create a new instance of MyFragment that will be initialized
     * with the given arguments.
     */
    static MyFragment newInstance(CharSequence label) {
        MyFragment f = new MyFragment();
        Bundle b = new Bundle();
        b.putCharSequence("label", label);
        f.setArguments(b);
        return f;
    }

    /**
     * Parse attributes during inflation from a view hierarchy into the
     * arguments we handle.
     */
    @Override
    public void onInflate(@NonNull Context context, @NonNull AttributeSet attrs,
            @Nullable Bundle savedInstanceState) {
        super.onInflate(context, attrs, savedInstanceState);

        TypedArray a = context.obtainStyledAttributes(attrs,
                R.styleable.FragmentArguments);
        mLabel = a.getText(R.styleable.FragmentArguments_android_label);
        a.recycle();
    }

    /**
     * During creation, if arguments have been supplied to the fragment
     * then parse those out.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Bundle args = getArguments();
        if (args != null) {
            CharSequence label = args.getCharSequence("label");
            if (label != null) {
                mLabel = label;
            }
        }
    }

    /**
     * Create the view for this fragment, using the arguments given to it.
     */
    @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(mLabel != null ? mLabel : "(no label)");
        ViewCompat.setBackground(
                tv, ContextCompat.getDrawable(getContext(), android.R.drawable.gallery_thumb));
        return v;
    }
}

Note that parsing the XML attributes uses a "styleable" resource. The declaration for the styleable used here is:

<declare-styleable name="FragmentArguments">
    <attr name="android:label" />
</declare-styleable>

The fragment can then be declared within its activity's content layout through a tag like this:

<androidx.fragment.app.FragmentContainerView
        class="com.example.android.supportv4.app.FragmentArgumentsSupport$MyFragment"
        android:id="@+id/embedded"
        android:layout_width="0px" android:layout_height="wrap_content"
        android:layout_weight="1"
        android:label="@string/fragment_arguments_embedded" />

This fragment can also be created dynamically from arguments given at runtime in the arguments Bundle; here is an example of doing so at creation of the containing activity:

@Override protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.fragment_arguments_support);

    if (savedInstanceState == null) {
        // First-time init; create fragment to embed in activity.
        FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
        Fragment newFragment = MyFragment.newInstance("From Arguments");
        ft.add(R.id.created, newFragment);
        ft.commit();
    }
}

public void onMultiWindowModeChanged(boolean isInMultiWindowMode)

Called when the Fragment's activity changes from fullscreen mode to multi-window mode and visa-versa. This is generally tied to onMultiWindowModeChanged of the containing Activity.

@MainThread
public boolean onOptionsItemSelected(@NonNull MenuItem item)

This hook is called whenever an item in your options menu is selected. The default implementation simply returns false to have the normal processing happen (calling the item's Runnable or sending a message to its Handler as appropriate). You can use this method for any items for which you would like to do processing without those other facilities.

Derived classes should call through to the base class for it to perform the default menu handling.

@MainThread
public void onOptionsMenuClosed(@NonNull Menu menu)

This hook is called whenever the options menu is being closed (either by the user canceling the menu with the back/menu button, or when an item is selected).

@MainThread
@CallSuper
public void onPause()

Called when the Fragment is no longer resumed. This is generally tied to Activity.onPause of the containing Activity's lifecycle.

public void onPictureInPictureModeChanged(boolean isInPictureInPictureMode)

Called by the system when the activity changes to and from picture-in-picture mode. This is generally tied to onPictureInPictureModeChanged of the containing Activity.

@MainThread
public void onPrepareOptionsMenu(@NonNull Menu menu)

Prepare the Fragment host's standard options menu to be displayed. This is called right before the menu is shown, every time it is shown. You can use this method to efficiently enable/disable items or otherwise dynamically modify the contents. See Activity.onPrepareOptionsMenu for more information.

@MainThread
public void onPrimaryNavigationFragmentChanged(
    boolean isPrimaryNavigationFragment
)

Callback for when the primary navigation state of this Fragment has changed. This can be the result of the getParentFragmentManager containing FragmentManager} having its primary navigation fragment changed via setPrimaryNavigationFragment or due to the primary navigation fragment changing in a parent FragmentManager.

public void onRequestPermissionsResult(
    int requestCode,
    @NonNull String[] permissions,
    @NonNull int[] grantResults
)

Callback for the result from requesting permissions. This method is invoked for every call on requestPermissions.

Note: It is possible that the permissions request interaction with the user is interrupted. In this case you will receive empty permissions and results arrays which should be treated as a cancellation.

@MainThread
@CallSuper
public void onResume()

Called when the fragment is visible to the user and actively running. This is generally tied to Activity.onResume of the containing Activity's lifecycle.

@MainThread
public void onSaveInstanceState(@NonNull Bundle outState)

Called to ask the fragment to save its current dynamic state, so it can later be reconstructed in a new instance if its process is restarted. If a new instance of the fragment later needs to be created, the data you place in the Bundle here will be available in the Bundle given to onCreate, onCreateView, and onViewCreated.

This corresponds to Activity.onSaveInstanceState(Bundle) and most of the discussion there applies here as well. Note however: this method may be called at any time before onDestroy. There are many situations where a fragment may be mostly torn down (such as when placed on the back stack with no UI showing), but its state will not be saved until its owning activity actually needs to save its state.

@MainThread
@CallSuper
public void onStart()

Called when the Fragment is visible to the user. This is generally tied to Activity.onStart of the containing Activity's lifecycle.

@MainThread
@CallSuper
public void onStop()

Called when the Fragment is no longer started. This is generally tied to Activity.onStop of the containing Activity's lifecycle.

@MainThread
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState)

Called immediately after onCreateView has returned, but before any saved state has been restored in to the view. This gives subclasses a chance to initialize themselves once they know their view hierarchy has been completely created. The fragment's view hierarchy is not however attached to its parent at this point.

@MainThread
@CallSuper
public void onViewStateRestored(@Nullable Bundle savedInstanceState)

Called when all saved state has been restored into the view hierarchy of the fragment. This can be used to do initialization based on saved state that you are letting the view hierarchy track itself, such as whether check box widgets are currently checked. This is called after onViewCreated and before onStart.

public @Nullable Context peekAvailableContext()

Get the Context if it is currently available. If this returns null, you can use addOnContextAvailableListener to receive a callback for when it available.

public void postponeEnterTransition()

Postpone the entering Fragment transition until startPostponedEnterTransition or executePendingTransactions has been called.

This method gives the Fragment the ability to delay Fragment animations until all data is loaded. Until then, the added, shown, and attached Fragments will be INVISIBLE and removed, hidden, and detached Fragments won't be have their Views removed. The transaction runs when all postponed added Fragments in the transaction have called startPostponedEnterTransition.

This method should be called before being added to the FragmentTransaction or in onCreate, onAttach, or onCreateView}. startPostponedEnterTransition must be called to allow the Fragment to start the transitions.

When a FragmentTransaction is started that may affect a postponed FragmentTransaction, based on which containers are in their operations, the postponed FragmentTransaction will have its start triggered. The early triggering may result in faulty or nonexistent animations in the postponed transaction. FragmentTransactions that operate only on independent containers will not interfere with each other's postponement.

Calling postponeEnterTransition on Fragments with a null View will not postpone the transition.

public final void postponeEnterTransition(long duration, @NonNull TimeUnit timeUnit)

Postpone the entering Fragment transition for a given amount of time and then call startPostponedEnterTransition.

This method gives the Fragment the ability to delay Fragment animations for a given amount of time. Until then, the added, shown, and attached Fragments will be INVISIBLE and removed, hidden, and detached Fragments won't be have their Views removed. The transaction runs when all postponed added Fragments in the transaction have called startPostponedEnterTransition.

This method should be called before being added to the FragmentTransaction or in onCreate, onAttach, or onCreateView}.

When a FragmentTransaction is started that may affect a postponed FragmentTransaction, based on which containers are in their operations, the postponed FragmentTransaction will have its start triggered. The early triggering may result in faulty or nonexistent animations in the postponed transaction. FragmentTransactions that operate only on independent containers will not interfere with each other's postponement.

Calling postponeEnterTransition on Fragments with a null View will not postpone the transition.

@MainThread
public final @NonNull ActivityResultLauncher<I> <I, O> registerForActivityResult(
    @NonNull ActivityResultContract<I, O> contract,
    @NonNull ActivityResultCallback<O> callback
)

Register a request to start an activity for result, designated by the given contract.

This creates a record in the registry associated with this caller, managing request code, as well as conversions to/from Intent under the hood.

This must be called unconditionally, as part of initialization path, typically as a field initializer of an Activity or Fragment.

If the host of this fragment is an ActivityResultRegistryOwner the ActivityResultRegistry of the host will be used. Otherwise, this will use the registry of the Fragment's Activity.

@MainThread
public final @NonNull ActivityResultLauncher<I> <I, O> registerForActivityResult(
    @NonNull ActivityResultContract<I, O> contract,
    @NonNull ActivityResultRegistry registry,
    @NonNull ActivityResultCallback<O> callback
)

Register a request to start an activity for result, designated by the given contract.

This creates a record in the given registry, managing request code, as well as conversions to/from Intent under the hood.

This must be called unconditionally, as part of initialization path, typically as a field initializer of an Activity or Fragment.

public void registerForContextMenu(@NonNull View view)

Registers a context menu to be shown for the given view (multiple views can show the context menu). This method will set the OnCreateContextMenuListener on the view to this fragment, so onCreateContextMenu will be called when it is time to show the context menu.

public void removeOnContextAvailableListener(
    @NonNull OnContextAvailableListener listener
)

Remove a OnContextAvailableListener previously added via addOnContextAvailableListener.

public final void requestPermissions(@NonNull String[] permissions, int requestCode)

Requests permissions to be granted to this application. These permissions must be requested in your manifest, they should not be granted to your app, and they should have protection level #PROTECTION_DANGEROUS dangerous, regardless whether they are declared by the platform or a third-party app.

Normal permissions PROTECTION_NORMAL are granted at install time if requested in the manifest. Signature permissions PROTECTION_SIGNATURE are granted at install time if requested in the manifest and the signature of your app matches the signature of the app declaring the permissions.

Call shouldShowRequestPermissionRationale before calling this API to check if the system recommends to show a rationale dialog before asking for a permission.

If your app does not have the requested permissions the user will be presented with UI for accepting them. After the user has accepted or rejected the requested permissions you will receive a callback on onRequestPermissionsResult reporting whether the permissions were granted or not.

Note that requesting a permission does not guarantee it will be granted and your app should be able to run without having this permission.

This method may start an activity allowing the user to choose which permissions to grant and which to reject. Hence, you should be prepared that your activity may be paused and resumed. Further, granting some permissions may require a restart of you application. In such a case, the system will recreate the activity stack before delivering the result to onRequestPermissionsResult.

When checking whether you have a permission you should use checkSelfPermission.

Calling this API for permissions already granted to your app would show UI to the user to decide whether the app can still hold these permissions. This can be useful if the way your app uses the data guarded by the permissions changes significantly.

public final @NonNull FragmentActivity requireActivity()

Return the FragmentActivity this fragment is currently associated with.

public final @NonNull Bundle requireArguments()

Return the arguments supplied when the fragment was instantiated.

public final @NonNull Context requireContext()

Return the Context this fragment is currently associated with.

public final @NonNull FragmentManager requireFragmentManager()

Return the FragmentManager for interacting with fragments associated with this fragment's activity. Note that this will be available slightly before getActivity, during the time from when the fragment is placed in a FragmentTransaction until it is committed and attached to its activity.

If this Fragment is a child of another Fragment, the FragmentManager returned here will be the parent's getChildFragmentManager.

public final @NonNull Object requireHost()

Return the host object of this fragment.

public final @NonNull Fragment requireParentFragment()

Returns the parent Fragment containing this Fragment.

public final @NonNull View requireView()

Get the root view for the fragment's layout (the one returned by onCreateView).

public void setAllowEnterTransitionOverlap(boolean allow)

Sets whether the the exit transition and enter transition overlap or not. When true, the enter transition will start as soon as possible. When false, the enter transition will wait until the exit transition completes before starting.

public void setAllowReturnTransitionOverlap(boolean allow)

Sets whether the the return transition and reenter transition overlap or not. When true, the reenter transition will start as soon as possible. When false, the reenter transition will wait until the return transition completes before starting.

public void setArguments(@Nullable Bundle args)

Supply the construction arguments for this fragment. The arguments supplied here will be retained across fragment destroy and creation.

This method cannot be called if the fragment is added to a FragmentManager and if isStateSaved would return true.

public void setEnterSharedElementCallback(@Nullable SharedElementCallback callback)

When custom transitions are used with Fragments, the enter transition callback is called when this Fragment is attached or detached when not popping the back stack.

public void setEnterTransition(@Nullable Object transition)

Sets the Transition that will be used to move Views into the initial scene. The entering Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as entering is governed by changing visibility from INVISIBLE to VISIBLE. If transition is null, entering Views will remain unaffected.

public void setExitSharedElementCallback(@Nullable SharedElementCallback callback)

When custom transitions are used with Fragments, the exit transition callback is called when this Fragment is attached or detached when popping the back stack.

public void setExitTransition(@Nullable Object transition)

Sets the Transition that will be used to move Views out of the scene when the fragment is removed, hidden, or detached when not popping the back stack. The exiting Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as exiting is governed by changing visibility from VISIBLE to INVISIBLE. If transition is null, the views will remain unaffected.

public void setHasOptionsMenu(boolean hasMenu)

Report that this fragment would like to participate in populating the options menu by receiving a call to onCreateOptionsMenu and related methods.

public void setInitialSavedState(@Nullable Fragment.SavedState state)

Set the initial saved state that this Fragment should restore itself from when first being constructed, as returned by FragmentManager.saveFragmentInstanceState.

public void setMenuVisibility(boolean menuVisible)

Set a hint for whether this fragment's menu should be visible. This is useful if you know that a fragment has been placed in your view hierarchy so that the user can not currently seen it, so any menu items it has should also not be shown.

public void setReenterTransition(@Nullable Object transition)

Sets the Transition that will be used to move Views in to the scene when returning due to popping a back stack. The entering Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as exiting is governed by changing visibility from VISIBLE to INVISIBLE. If transition is null, the views will remain unaffected. If nothing is set, the default will be to use the same transition as getExitTransition.

public void setRetainInstance(boolean retain)

Control whether a fragment instance is retained across Activity re-creation (such as from a configuration change). If set, the fragment lifecycle will be slightly different when an activity is recreated:

• onDestroy will not be called (but onDetach still will be, because the fragment is being detached from its current activity).
• onCreate will not be called since the fragment is not being re-created.
• onAttach and onActivityCreatedwill still be called.

public void setReturnTransition(@Nullable Object transition)

Sets the Transition that will be used to move Views out of the scene when the Fragment is preparing to be removed, hidden, or detached because of popping the back stack. The exiting Views will be those that are regular Views or ViewGroups that have isTransitionGroup return true. Typical Transitions will extend android.transition.Visibility as entering is governed by changing visibility from VISIBLE to INVISIBLE. If transition is null, entering Views will remain unaffected. If nothing is set, the default will be to use the same value as set in setEnterTransition.

public void setSharedElementEnterTransition(@Nullable Object transition)

Sets the Transition that will be used for shared elements transferred into the content Scene. Typical Transitions will affect size and location, such as android.transition.ChangeBounds. A null value will cause transferred shared elements to blink to the final position.

public void setSharedElementReturnTransition(@Nullable Object transition)

Sets the Transition that will be used for shared elements transferred back during a pop of the back stack. This Transition acts in the leaving Fragment. Typical Transitions will affect size and location, such as android.transition.ChangeBounds. A null value will cause transferred shared elements to blink to the final position. If no value is set, the default will be to use the same value as setSharedElementEnterTransition.

public void setTargetFragment(@Nullable Fragment fragment, int requestCode)

Optional target for this fragment. This may be used, for example, if this fragment is being started by another, and when done wants to give a result back to the first. The target set here is retained across instances via FragmentManager.putFragment().

public void setUserVisibleHint(boolean isVisibleToUser)

Set a hint to the system about whether this fragment's UI is currently visible to the user. This hint defaults to true and is persistent across fragment instance state save and restore.

An app may set this to false to indicate that the fragment's UI is scrolled out of visibility or is otherwise not directly visible to the user. This may be used by the system to prioritize operations such as fragment lifecycle updates or loader ordering behavior.

Note: This method may be called outside of the fragment lifecycle. and thus has no ordering guarantees with regard to fragment lifecycle method calls.