FragmentNavigator

Artifact: androidx.navigation:navigation-fragment

View Source

Added in 1.0.0

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Kotlin |Java

@Navigator.Name(value = "fragment")
public class FragmentNavigator extends Navigator

java.lang.Object
↳	androidx.navigation.Navigator
	↳	androidx.navigation.fragment.FragmentNavigator

Known direct subclasses

DynamicFragmentNavigator

DynamicFragmentNavigator

The Navigator that enables navigating to destinations within dynamic feature modules.

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Navigator that navigates through fragment transactions. Every destination using this Navigator must set a valid Fragment class name with android:name or Destination.setClassName.

The current Fragment from FragmentNavigator's perspective can be retrieved by calling FragmentManager.getPrimaryNavigationFragment with the FragmentManager passed to this FragmentNavigator.

Note that the default implementation does Fragment transactions asynchronously, so the current Fragment will not be available immediately (i.e., in callbacks to NavController.OnDestinationChangedListener).

FragmentNavigator respects Log.isLoggable for debug logging, allowing you to use adb shell setprop log.tag.FragmentNavigator VERBOSE.

Summary

Nested types
@NavDestination.ClassType(value = Fragment) public class FragmentNavigator.Destination extends NavDestination NavDestination specific to FragmentNavigator
public final class FragmentNavigator.Extras implements Navigator.Extras Extras that can be passed to FragmentNavigator to enable Fragment specific behavior
public final class FragmentNavigator.Extras.Builder Builder for constructing new Extras instances.

Public constructors
FragmentNavigator(     @NonNull Context context,     @NonNull FragmentManager fragmentManager,     int containerId )

Public methods
@NonNull FragmentNavigator.Destination	createDestination() Construct a new NavDestination associated with this Navigator.
@NonNull Fragment	instantiateFragment(     @NonNull Context context,     @NonNull FragmentManager fragmentManager,     @NonNull String className,     Bundle args ) This method is deprecated. Set a custom {@link androidx.fragment.app.FragmentFactory} via {@link FragmentManager#setFragmentFactory(FragmentFactory)} to control instantiation of Fragments.
void	navigate(     @NonNull List<@NonNull NavBackStackEntry> entries,     NavOptions navOptions,     Navigator.Extras navigatorExtras ) {@inheritDoc}
void	onAttach(@NonNull NavigatorState state) Indicator that this Navigator is actively being used by a NavController.
void	onLaunchSingleTop(@NonNull NavBackStackEntry backStackEntry) {@inheritDoc}
void	onRestoreState(@NonNull Bundle savedState) Restore any state previously saved in onSaveState.
Bundle	onSaveState() Called to ask for a Bundle representing the Navigator's state.
void	popBackStack(@NonNull NavBackStackEntry popUpTo, boolean savedState) {@inheritDoc}

Inherited methods

From androidx.navigation.Navigator final @NonNull NavigatorState getState() The state of the Navigator is the communication conduit between the Navigator and the NavController that has called onAttach. final boolean isAttached() Whether this Navigator is actively being used by a NavController. NavDestination navigate(     @NonNull FragmentNavigator.Destination destination,     Bundle args,     NavOptions navOptions,     Navigator.Extras navigatorExtras ) Navigate to a destination. boolean popBackStack() Attempt to pop this navigator's back stack, performing the appropriate navigation.

Public constructors

FragmentNavigator

Added in 2.0.0

public FragmentNavigator(
    @NonNull Context context,
    @NonNull FragmentManager fragmentManager,
    int containerId
)

Public methods

createDestination

Added in 1.0.0

public @NonNull FragmentNavigator.Destination createDestination()

Construct a new NavDestination associated with this Navigator.

Any initialization of the destination should be done in the destination's constructor as it is not guaranteed that every destination will be created through this method.

Returns
@NonNull FragmentNavigator.Destination	a new NavDestination

instantiateFragment

Added in 2.0.0

Deprecated in 2.1.0

public @NonNull Fragment instantiateFragment(
    @NonNull Context context,
    @NonNull FragmentManager fragmentManager,
    @NonNull String className,
    Bundle args
)

This method is deprecated.
Set a custom {@link androidx.fragment.app.FragmentFactory} via {@link FragmentManager#setFragmentFactory(FragmentFactory)} to control instantiation of Fragments.

Instantiates the Fragment via the FragmentManager's androidx.fragment.app.FragmentFactory.

Note that this method is not responsible for calling Fragment.setArguments on the returned Fragment instance.

Parameters
@NonNull Context context	Context providing the correct ClassLoader
@NonNull FragmentManager fragmentManager	FragmentManager the Fragment will be added to
@NonNull String className	The Fragment to instantiate
Bundle args	The Fragment's arguments, if any

Returns
@NonNull Fragment	A new fragment instance.

navigate

public void navigate(
    @NonNull List<@NonNull NavBackStackEntry> entries,
    NavOptions navOptions,
    Navigator.Extras navigatorExtras
)

{@inheritDoc}

This method should always call FragmentTransaction.setPrimaryNavigationFragment so that the Fragment associated with the new destination can be retrieved with FragmentManager.getPrimaryNavigationFragment.

Note that the default implementation commits the new Fragment asynchronously, so the new Fragment is not instantly available after this call completes.

This call will be ignored if the FragmentManager state has already been saved.

onAttach

public void onAttach(@NonNull NavigatorState state)

Indicator that this Navigator is actively being used by a NavController. This is called when the NavController's state is ready to be restored.

onLaunchSingleTop

public void onLaunchSingleTop(@NonNull NavBackStackEntry backStackEntry)

{@inheritDoc}

This method should always call FragmentTransaction.setPrimaryNavigationFragment so that the Fragment associated with the new destination can be retrieved with FragmentManager.getPrimaryNavigationFragment.

Note that the default implementation commits the new Fragment asynchronously, so the new Fragment is not instantly available after this call completes.

This call will be ignored if the FragmentManager state has already been saved.

onRestoreState

public void onRestoreState(@NonNull Bundle savedState)

Restore any state previously saved in onSaveState. This will be called before any calls to navigate or popBackStack.

Calls to createDestination should not be dependent on any state restored here as createDestination can be called before the state is restored.

Parameters
@NonNull Bundle savedState	The state previously saved

onSaveState

public Bundle onSaveState()

Called to ask for a Bundle representing the Navigator's state. This will be restored in onRestoreState.

popBackStack

public void popBackStack(@NonNull NavBackStackEntry popUpTo, boolean savedState)

{@inheritDoc}

This method must call FragmentTransaction.setPrimaryNavigationFragment if the pop succeeded so that the newly visible Fragment can be retrieved with FragmentManager.getPrimaryNavigationFragment.

Note that the default implementation pops the Fragment asynchronously, so the newly visible Fragment from the back stack is not instantly available after this call completes.