Android APIs
public class

BrowseSupportFragment

extends Fragment
java.lang.Object
   ↳ android.support.v4.app.Fragment
     ↳ android.support.v17.leanback.app.BrowseSupportFragment

Class Overview

A fragment for creating Leanback browse screens. It is composed of a RowsSupportFragment and a HeadersSupportFragment.

A BrowseSupportFragment renders the elements of its ObjectAdapter as a set of rows in a vertical list. The elements in this adapter must be subclasses of Row.

The HeadersSupportFragment can be set to be either shown or hidden by default, or may be disabled entirely. See setHeadersState(int) for details.

By default the BrowseSupportFragment includes support for returning to the headers when the user presses Back. For Activities that customize onBackPressed(), you must disable this default Back key support by calling setHeadersTransitionOnBackEnabled(boolean) with false and use BrowseSupportFragment.BrowseTransitionListener and startHeadersTransition(boolean).

The recommended theme to use with a BrowseSupportFragment is Theme_Leanback_Browse.

Summary

Nested Classes
class BrowseSupportFragment.BrowseTransitionListener Listener for transitions between browse headers and rows. 
Constants
int HEADERS_DISABLED The headers fragment is disabled and will never be shown.
int HEADERS_ENABLED The headers fragment is enabled and shown by default.
int HEADERS_HIDDEN The headers fragment is enabled and hidden by default.
Public Constructors
BrowseSupportFragment()
Public Methods
static Bundle createArgs(Bundle args, String title, int headersState)
Creates arguments for a browse fragment.
void enableRowScaling(boolean enable)
Enables scaling of rows when headers are present.
ObjectAdapter getAdapter()
Returns the adapter containing the rows for the fragment.
Drawable getBadgeDrawable()
Returns the badge drawable used in the fragment title.
int getBrandColor()
Returns the brand color for the browse fragment.
int getHeadersState()
Returns the state of the headers column in the browse fragment.
OnItemViewClickedListener getOnItemViewClickedListener()
Returns the item Clicked listener.
OnItemViewSelectedListener getOnItemViewSelectedListener()
Returns an item selection listener.
int getSearchAffordanceColor()
Returns the color used to draw the search affordance.
SearchOrbView.Colors getSearchAffordanceColors()
Returns the SearchOrbView.Colors used to draw the search affordance.
String getTitle()
Returns the title for the browse fragment.
final boolean isHeadersTransitionOnBackEnabled()
Returns true if headers transition on back key support is enabled.
boolean isInHeadersTransition()
Returns true if the headers transition is currently running.
boolean isShowingHeaders()
Returns true if headers are shown.
void onCreate(Bundle savedInstanceState)
Called to do initial creation of a fragment.
View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
Called to have the fragment instantiate its user interface view.
void onDestroy()
Called when the fragment is no longer in use.
void onDestroyView()
Called when the view previously created by onCreateView(LayoutInflater, ViewGroup, Bundle) has been detached from the fragment.
void onPause()
Called when the Fragment is no longer resumed.
void onResume()
Called when the fragment is visible to the user and actively running.
void onSaveInstanceState(Bundle outState)
Called to ask the fragment to save its current dynamic state, so it can later be reconstructed in a new instance of its process is restarted.
void onStart()
Called when the Fragment is visible to the user.
void onViewCreated(View view, Bundle savedInstanceState)
Called immediately after onCreateView(LayoutInflater, ViewGroup, Bundle) has returned, but before any saved state has been restored in to the view.
void prepareEntranceTransition()
Enables entrance transition.
void setAdapter(ObjectAdapter adapter)
Sets the adapter containing the rows for the fragment.
void setBadgeDrawable(Drawable drawable)
Sets the drawable displayed in the browse fragment title.
void setBrandColor(int color)
Sets the brand color for the browse fragment.
void setBrowseTransitionListener(BrowseSupportFragment.BrowseTransitionListener listener)
Sets a listener for browse fragment transitions.
void setHeaderPresenterSelector(PresenterSelector headerPresenterSelector)
Sets the PresenterSelector used to render the row headers.
void setHeadersState(int headersState)
Sets the state for the headers column in the browse fragment.
final void setHeadersTransitionOnBackEnabled(boolean headersBackStackEnabled)
Enables/disables headers transition on back key support.
void setOnItemViewClickedListener(OnItemViewClickedListener listener)
Sets an item clicked listener on the fragment.
void setOnItemViewSelectedListener(OnItemViewSelectedListener listener)
Sets an item selection listener.
void setOnSearchClickedListener(View.OnClickListener listener)
Sets a click listener for the search affordance.
void setSearchAffordanceColor(int color)
Sets the color used to draw the search affordance.
void setSearchAffordanceColors(SearchOrbView.Colors colors)
Sets the SearchOrbView.Colors used to draw the search affordance.
void setSelectedPosition(int position, boolean smooth)
Sets the selected row position.
void setSelectedPosition(int position)
Sets the selected row position with smooth animation.
void setTitle(String title)
Sets a title for the browse fragment.
void startEntranceTransition()
When fragment finishes loading data, it should call startEntranceTransition() to execute the entrance transition.
void startHeadersTransition(boolean withHeaders)
Starts a headers transition.
Protected Methods
Object createEntranceTransition()
Create entrance transition.
void onEntranceTransitionEnd()
Callback when entrance transition is ended.
void onEntranceTransitionPrepare()
Callback when entrance transition is prepared.
void onEntranceTransitionStart()
Callback when entrance transition is started.
void runEntranceTransition(Object entranceTransition)
Run entrance transition.
[Expand]
Inherited Methods
From class android.support.v4.app.Fragment
From class java.lang.Object
From interface android.content.ComponentCallbacks
From interface android.view.View.OnCreateContextMenuListener

Constants

public static final int HEADERS_DISABLED

The headers fragment is disabled and will never be shown.

Constant Value: 3 (0x00000003)

public static final int HEADERS_ENABLED

The headers fragment is enabled and shown by default.

Constant Value: 1 (0x00000001)

public static final int HEADERS_HIDDEN

The headers fragment is enabled and hidden by default.

Constant Value: 2 (0x00000002)

Public Constructors

public BrowseSupportFragment ()

Public Methods

public static Bundle createArgs (Bundle args, String title, int headersState)

Creates arguments for a browse fragment.

Parameters
args The Bundle to place arguments into, or null if the method should return a new Bundle.
title The title of the BrowseSupportFragment.
headersState The initial state of the headers of the BrowseSupportFragment. Must be one of HEADERS_ENABLED, HEADERS_HIDDEN, or HEADERS_DISABLED.
Returns
  • A Bundle with the given arguments for creating a BrowseSupportFragment.

public void enableRowScaling (boolean enable)

Enables scaling of rows when headers are present. By default enabled to increase density.

Parameters
enable true to enable row scaling

public ObjectAdapter getAdapter ()

Returns the adapter containing the rows for the fragment.

public Drawable getBadgeDrawable ()

Returns the badge drawable used in the fragment title.

public int getBrandColor ()

Returns the brand color for the browse fragment. The default is transparent.

public int getHeadersState ()

Returns the state of the headers column in the browse fragment.

public OnItemViewClickedListener getOnItemViewClickedListener ()

Returns the item Clicked listener.

public OnItemViewSelectedListener getOnItemViewSelectedListener ()

Returns an item selection listener.

public int getSearchAffordanceColor ()

Returns the color used to draw the search affordance.

public SearchOrbView.Colors getSearchAffordanceColors ()

Returns the SearchOrbView.Colors used to draw the search affordance.

public String getTitle ()

Returns the title for the browse fragment.

public final boolean isHeadersTransitionOnBackEnabled ()

Returns true if headers transition on back key support is enabled.

public boolean isInHeadersTransition ()

Returns true if the headers transition is currently running.

public boolean isShowingHeaders ()

Returns true if headers are shown.

public void onCreate (Bundle savedInstanceState)

Called to do initial creation of a fragment. This is called after onAttach(Activity) and before onCreateView(LayoutInflater, ViewGroup, Bundle).

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, see onActivityCreated(Bundle).

Parameters
savedInstanceState If the fragment is being re-created from a previous saved state, this is the state.

public View onCreateView (LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)

Called to have the fragment instantiate its user interface view. This is optional, and non-graphical fragments can return null (which is the default implementation). This will be called between onCreate(Bundle) and onActivityCreated(Bundle).

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

Parameters
inflater The LayoutInflater object that can be used to inflate any views in the fragment,
container If non-null, this is the parent view that the fragment's UI should be attached to. The fragment should not add the view itself, but this can be used to generate the LayoutParams of the view.
savedInstanceState If non-null, this fragment is being re-constructed from a previous saved state as given here.
Returns
  • Return the View for the fragment's UI, or null.

public void onDestroy ()

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

public void onDestroyView ()

Called when the view previously created by onCreateView(LayoutInflater, ViewGroup, Bundle) 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(LayoutInflater, ViewGroup, Bundle) 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.

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 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.

public void onSaveInstanceState (Bundle outState)

Called to ask the fragment to save its current dynamic state, so it can later be reconstructed in a new instance of 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(Bundle), onCreateView(LayoutInflater, ViewGroup, Bundle), and onActivityCreated(Bundle).

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.

Parameters
outState Bundle in which to place your saved state.

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.

public void onViewCreated (View view, Bundle savedInstanceState)

Called immediately after onCreateView(LayoutInflater, ViewGroup, Bundle) 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.

Parameters
view The View returned by onCreateView(LayoutInflater, ViewGroup, Bundle).
savedInstanceState If non-null, this fragment is being re-constructed from a previous saved state as given here.

public void prepareEntranceTransition ()

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.

    public void setAdapter (ObjectAdapter adapter)

    Sets the adapter containing the rows for the fragment.

    The items referenced by the adapter must be be derived from Row. These rows will be used by the rows fragment and the headers fragment (if not disabled) to render the browse rows.

    Parameters
    adapter An ObjectAdapter for the browse rows. All items must derive from Row.

    public void setBadgeDrawable (Drawable drawable)

    Sets the drawable displayed in the browse fragment title.

    Parameters
    drawable The Drawable to display in the browse fragment title.

    public void setBrandColor (int color)

    Sets the brand color for the browse fragment. The brand color is used as the primary color for UI elements in the browse fragment. For example, the background color of the headers fragment uses the brand color.

    Parameters
    color The color to use as the brand color of the fragment.

    public void setBrowseTransitionListener (BrowseSupportFragment.BrowseTransitionListener listener)

    Sets a listener for browse fragment transitions.

    Parameters
    listener The listener to call when a browse headers transition begins or ends.

    public void setHeaderPresenterSelector (PresenterSelector headerPresenterSelector)

    Sets the PresenterSelector used to render the row headers.

    Parameters
    headerPresenterSelector The PresenterSelector that will determine the Presenter for each row header.

    public void setHeadersState (int headersState)

    Sets the state for the headers column in the browse fragment. Must be one of HEADERS_ENABLED, HEADERS_HIDDEN, or HEADERS_DISABLED.

    Parameters
    headersState The state of the headers for the browse fragment.

    public final void setHeadersTransitionOnBackEnabled (boolean headersBackStackEnabled)

    Enables/disables headers transition on back key support. This is enabled by default. The BrowseSupportFragment will add a back stack entry when headers are showing. Running a headers transition when the back key is pressed only works when the headers state is HEADERS_ENABLED or HEADERS_HIDDEN.

    NOTE: If an Activity has its own onBackPressed() handling, you must disable this feature. You may use startHeadersTransition(boolean) and BrowseSupportFragment.BrowseTransitionListener in your own back stack handling.

    public void setOnItemViewClickedListener (OnItemViewClickedListener listener)

    Sets an item clicked listener on the fragment. OnItemViewClickedListener will override View.OnClickListener that item presenter sets during onCreateViewHolder(ViewGroup). So in general, developer should choose one of the listeners but not both.

    public void setOnItemViewSelectedListener (OnItemViewSelectedListener listener)

    Sets an item selection listener.

    public void setOnSearchClickedListener (View.OnClickListener listener)

    Sets a click listener for the search affordance.

    The presence of a listener will change the visibility of the search affordance in the fragment title. When set to non-null, the title will contain an element that a user may click to begin a search.

    The listener's onClick method will be invoked when the user clicks on the search element.

    Parameters
    listener The listener to call when the search element is clicked.

    public void setSearchAffordanceColor (int color)

    Sets the color used to draw the search affordance. A default brighter color will be set by the framework.

    Parameters
    color The color to use for the search affordance.

    public void setSearchAffordanceColors (SearchOrbView.Colors colors)

    Sets the SearchOrbView.Colors used to draw the search affordance.

    public void setSelectedPosition (int position, boolean smooth)

    Sets the selected row position.

    public void setSelectedPosition (int position)

    Sets the selected row position with smooth animation.

    public void setTitle (String title)

    Sets a title for the browse fragment.

    Parameters
    title The title of the browse fragment.

    public void startEntranceTransition ()

    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.

    public void startHeadersTransition (boolean withHeaders)

    Starts a headers transition.

    This method will begin a transition to either show or hide the headers, depending on the value of withHeaders. If headers are disabled for this browse fragment, this method will throw an exception.

    Parameters
    withHeaders True if the headers should transition to being shown, false if the transition should result in headers being hidden.

    Protected Methods

    protected Object createEntranceTransition ()

    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.

    protected void onEntranceTransitionEnd ()

    Callback when entrance transition is ended.

    protected void onEntranceTransitionPrepare ()

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

    protected void onEntranceTransitionStart ()

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

    protected void runEntranceTransition (Object entranceTransition)

    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.