ObjectAdapter

Kotlin |Java

public abstract class ObjectAdapter

Known direct subclasses

ArrayObjectAdapter, CursorObjectAdapter, PagingDataAdapter, SparseArrayObjectAdapter

`ArrayObjectAdapter`	An `ObjectAdapter` implemented with an `ArrayList`.
`CursorObjectAdapter`	An `ObjectAdapter` implemented with a `Cursor`.
`PagingDataAdapter`	An `ObjectAdapter` implemented with an `AsyncPagingDataDiffer`.
`SparseArrayObjectAdapter`	An `ObjectAdapter` implemented with a `android.util.SparseArray`.

Base class adapter to be used in leanback activities. Provides access to a data model and is decoupled from the presentation of the items via PresenterSelector.

Summary

Nested types
`public abstract class ObjectAdapter.DataObserver` A DataObserver can be notified when an ObjectAdapter's underlying data changes.

Constants
`static final int`	`NO_ID = -1` Indicates that an id has not been set.

Public constructors
`ObjectAdapter()` Constructs an adapter.
`ObjectAdapter(Presenter presenter)` Constructs an adapter that uses the given `Presenter` for all items.
`ObjectAdapter(PresenterSelector presenterSelector)` Constructs an adapter with the given `PresenterSelector`.

Public methods
`abstract Object`	`get(int position)` Returns the item for the given position.
`long`	`getId(int position)` Returns the id for the given position.
`final Presenter`	`getPresenter(Object item)` Returns the `Presenter` for the given item from the adapter.
`final PresenterSelector`	`getPresenterSelector()` Returns the presenter selector for this ObjectAdapter.
`final boolean`	`hasStableIds()` Returns true if the item ids are stable across changes to the underlying data.
`boolean`	`isImmediateNotifySupported()` Returns true if the adapter pairs each underlying data change with a call to notify and false otherwise.
`final void`	`notifyItemRangeChanged(int positionStart, int itemCount, Object payload)` Notifies UI that some items has changed.
`final void`	`notifyItemRangeChanged(int positionStart, int itemCount)` Notifies UI that some items has changed.
`final void`	`registerObserver(ObjectAdapter.DataObserver observer)` Registers a DataObserver for data change notifications.
`final void`	`setHasStableIds(boolean hasStableIds)` Sets whether the item ids are stable across changes to the underlying data.
`final void`	`setPresenterSelector(PresenterSelector presenterSelector)` Sets the presenter selector.
`abstract int`	`size()` Returns the number of items in the adapter.
`final void`	`unregisterAllObservers()` Unregisters all DataObservers for this ObjectAdapter.
`final void`	`unregisterObserver(ObjectAdapter.DataObserver observer)` Unregisters a DataObserver for data change notifications.

Protected methods
`final void`	`notifyChanged()` Notifies UI that the underlying data has changed.
`final void`	`notifyItemMoved(int fromPosition, int toPosition)` Notifies UI that item at fromPosition has been moved to toPosition.
`final void`	`notifyItemRangeInserted(int positionStart, int itemCount)` Notifies UI that new items has been inserted.
`final void`	`notifyItemRangeRemoved(int positionStart, int itemCount)` Notifies UI that some items that has been removed.
`void`	`onHasStableIdsChanged()` Called when `setHasStableIds` is called and the status of stable ids has changed.
`void`	`onPresenterSelectorChanged()` Called when `setPresenterSelector` is called and the PresenterSelector differs from the previous one.

Constants

NO_ID

public static final int NO_ID = -1

Indicates that an id has not been set.

Public constructors

ObjectAdapter

public ObjectAdapter()

Constructs an adapter.

public ObjectAdapter(Presenter presenter)

Constructs an adapter that uses the given Presenter for all items.

public ObjectAdapter(PresenterSelector presenterSelector)

Constructs an adapter with the given PresenterSelector.

Public methods

get

public abstract Object get(int position)

Returns the item for the given position.

getId

public long getId(int position)

Returns the id for the given position.

getPresenter

public final Presenter getPresenter(Object item)

Returns the Presenter for the given item from the adapter.

getPresenterSelector

public final PresenterSelector getPresenterSelector()

Returns the presenter selector for this ObjectAdapter.

hasStableIds

public final boolean hasStableIds()

Returns true if the item ids are stable across changes to the underlying data. When this is true, clients of the ObjectAdapter can use getId to correlate Objects across changes.

isImmediateNotifySupported

public boolean isImmediateNotifySupported()

Returns true if the adapter pairs each underlying data change with a call to notify and false otherwise.

notifyItemRangeChanged

public final void notifyItemRangeChanged(int positionStart, int itemCount, Object payload)

Notifies UI that some items has changed.

Parameters
`int positionStart`	Starting position of the changed items.
`int itemCount`	Total number of items that changed.
`Object payload`	Optional parameter, use null to identify a "full" update.

notifyItemRangeChanged

public final void notifyItemRangeChanged(int positionStart, int itemCount)

Notifies UI that some items has changed.

Parameters
`int positionStart`	Starting position of the changed items.
`int itemCount`	Total number of items that changed.

public final void registerObserver(ObjectAdapter.DataObserver observer)

Registers a DataObserver for data change notifications.

setHasStableIds

public final void setHasStableIds(boolean hasStableIds)

Sets whether the item ids are stable across changes to the underlying data.

public final void setPresenterSelector(PresenterSelector presenterSelector)

Sets the presenter selector. May not be null.

size

public abstract int size()

Returns the number of items in the adapter.

unregisterAllObservers

public final void unregisterAllObservers()

Unregisters all DataObservers for this ObjectAdapter.

public final void unregisterObserver(ObjectAdapter.DataObserver observer)

Unregisters a DataObserver for data change notifications.

Protected methods

notifyChanged

protected final void notifyChanged()

Notifies UI that the underlying data has changed.

notifyItemMoved

protected final void notifyItemMoved(int fromPosition, int toPosition)

Notifies UI that item at fromPosition has been moved to toPosition.

Parameters
`int fromPosition`	Previous position of the item.
`int toPosition`	New position of the item.

notifyItemRangeInserted

protected final void notifyItemRangeInserted(int positionStart, int itemCount)

Notifies UI that new items has been inserted.

Parameters
`int positionStart`	Position where new items has been inserted.
`int itemCount`	Count of the new items has been inserted.

notifyItemRangeRemoved

protected final void notifyItemRangeRemoved(int positionStart, int itemCount)

Notifies UI that some items that has been removed.

Parameters
`int positionStart`	Starting position of the removed items.
`int itemCount`	Total number of items that has been removed.

onHasStableIdsChanged

protected void onHasStableIdsChanged()

Called when setHasStableIds is called and the status of stable ids has changed.

onPresenterSelectorChanged

protected void onPresenterSelectorChanged()

Called when setPresenterSelector is called and the PresenterSelector differs from the previous one.

ObjectAdapter

Summary

Nested types

Constants

Public constructors

Public methods

Protected methods

Constants

NO_ID

Public constructors

ObjectAdapter

ObjectAdapter

ObjectAdapter

Public methods

get

getId

getPresenter

getPresenterSelector

hasStableIds

isImmediateNotifySupported

notifyItemRangeChanged

notifyItemRangeChanged

registerObserver

setHasStableIds

setPresenterSelector

size

unregisterAllObservers

unregisterObserver

Protected methods

notifyChanged

notifyItemMoved

notifyItemRangeInserted

notifyItemRangeRemoved

onHasStableIdsChanged

onPresenterSelectorChanged