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BaseFragment

open class BaseFragment : BrandedFragment
kotlin.Any
   ↳ android.app.Fragment
   ↳ androidx.leanback.app.BrandedFragment
   ↳ androidx.leanback.app.BaseFragment

Base class for leanback Fragments. This class is not intended to be subclassed by apps.

Summary

Public methods
open Unit
onViewCreated(@NonNull view: View, @Nullable savedInstanceState: Bundle?)

open Unit
onCreate(savedInstanceState: Bundle!)

open Unit

When fragment finishes loading data, it should call startEntranceTransition() to execute the entrance transition.

open Unit

Enables entrance transition.

ProgressBarManager!

Returns the ProgressBarManager.

Protected methods
open Any!

Create entrance transition.

open Unit

Callback when entrance transition is started.

open Unit
runEntranceTransition(entranceTransition: Any!)

Run entrance transition.

open Unit

Callback when entrance transition is ended.

open Unit

Callback when entrance transition is prepared.

Inherited functions

Public methods

onViewCreated

open fun onViewCreated(@NonNull view: View, @Nullable savedInstanceState: Bundle?): Unit

onCreate

open fun onCreate(savedInstanceState: Bundle!): Unit

startEntranceTransition

open fun startEntranceTransition(): Unit

When fragment finishes loading data, it should call startEntranceTransition() to execute the entrance transition. startEntranceTransition() will start transition only if both two conditions are satisfied:

  • prepareEntranceTransition() was called.
  • has not executed entrance transition yet.
  • If startEntranceTransition() is called before onViewCreated(), it will be pending and executed when view is created.

    prepareEntranceTransition

    open fun prepareEntranceTransition(): Unit

    Enables entrance transition.

    Entrance transition is the standard slide-in transition that shows rows of data in browse screen and details screen.

    The method is ignored before LOLLIPOP (API21).

    This method must be called in or before onCreate(). Typically entrance transition should be enabled when savedInstance is null so that fragment restored from instanceState does not run an extra entrance transition. When the entrance transition is enabled, the fragment will make headers and content hidden initially. When data of rows are ready, app must call startEntranceTransition() to kick off the transition, otherwise the rows will be invisible forever.

    It is similar to android:windowsEnterTransition and can be considered a late-executed android:windowsEnterTransition controlled by app. There are two reasons that app needs it:

  • Workaround the problem that activity transition is not available between launcher and app. Browse activity must programmatically start the slide-in transition.
  • Separates DetailsOverviewRow transition from other rows transition. So that the DetailsOverviewRow transition can be executed earlier without waiting for all rows to be loaded.
  • Transition object is returned by createEntranceTransition(). Typically the app does not need override the default transition that browse and details provides.

    getProgressBarManager

    fun getProgressBarManager(): ProgressBarManager!

    Returns the ProgressBarManager.

    Return
    ProgressBarManager!: The ProgressBarManager.

    Protected methods

    createEntranceTransition

    protected open fun createEntranceTransition(): Any!

    Create entrance transition. Subclass can override to load transition from resource or construct manually. Typically app does not need to override the default transition that browse and details provides.

    onEntranceTransitionStart

    protected open fun onEntranceTransitionStart(): Unit

    Callback when entrance transition is started. This is when fragment should stop processing layout.

    runEntranceTransition

    protected open fun runEntranceTransition(entranceTransition: Any!): Unit

    Run entrance transition. Subclass may use TransitionManager to perform go(Scene) or beginDelayedTransition(). App should not override the default implementation of browse and details fragment.

    onEntranceTransitionEnd

    protected open fun onEntranceTransitionEnd(): Unit

    Callback when entrance transition is ended.

    onEntranceTransitionPrepare

    protected open fun onEntranceTransitionPrepare(): Unit

    Callback when entrance transition is prepared. This is when fragment should stop user input and animations.