PositionalDataSource.LoadInitialCallback
public
static
abstract
class
PositionalDataSource.LoadInitialCallback
extends Object
java.lang.Object | |
↳ | android.arch.paging.PositionalDataSource.LoadInitialCallback<T> |
Callback for loadInitial(LoadInitialParams, LoadInitialCallback)
to return data, position, and count.
A callback should be called only once, and may throw if called again.
It is always valid for a DataSource loading method that takes a callback to stash the callback and call it later. This enables DataSources to be fully asynchronous, and to handle temporary, recoverable error states (such as a network error that can be retried).
Summary
Public constructors | |
---|---|
PositionalDataSource.LoadInitialCallback()
|
Public methods | |
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abstract
void
|
onResult(List<T> data, int position, int totalCount)
Called to pass initial load state from a DataSource. |
abstract
void
|
onResult(List<T> data, int position)
Called to pass initial load state from a DataSource without total count, when placeholders aren't requested. |
Inherited methods | |
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Public constructors
PositionalDataSource.LoadInitialCallback
PositionalDataSource.LoadInitialCallback ()
Public methods
onResult
void onResult (List<T> data, int position, int totalCount)
Called to pass initial load state from a DataSource.
Call this method from your DataSource's loadInitial
function to return data,
and inform how many placeholders should be shown before and after. If counting is cheap
to compute (for example, if a network load returns the information regardless), it's
recommended to pass the total size to the totalCount parameter. If placeholders are not
requested (when placeholdersEnabled
is false), you can instead
call onResult(List, int)
.
Parameters | |
---|---|
data |
List : List of items loaded from the DataSource. If this is empty, the DataSource
is treated as empty, and no further loads will occur. |
position |
int : Position of the item at the front of the list. If there are N
items before the items in data that can be loaded from this DataSource,
pass N . |
totalCount |
int : Total number of items that may be returned from this DataSource.
Includes the number in the initial data parameter
as well as any items that can be loaded in front or behind of
data .
|
onResult
void onResult (List<T> data, int position)
Called to pass initial load state from a DataSource without total count, when placeholders aren't requested.
Note: This method can only be called when placeholders
are disabled (placeholdersEnabled
is false).
Call this method from your DataSource's loadInitial
function to return data,
if position is known but total size is not. If placeholders are requested, call the three
parameter variant: onResult(List, int, int)
.
Parameters | |
---|---|
data |
List : List of items loaded from the DataSource. If this is empty, the DataSource
is treated as empty, and no further loads will occur. |
position |
int : Position of the item at the front of the list. If there are N
items before the items in data that can be provided by this DataSource,
pass N .
|
Interfaces
Classes
- AsyncPagedListDiffer
- DataSource
- DataSource.Factory
- ItemKeyedDataSource
- ItemKeyedDataSource.LoadCallback
- ItemKeyedDataSource.LoadInitialCallback
- ItemKeyedDataSource.LoadInitialParams
- ItemKeyedDataSource.LoadParams
- LivePagedListBuilder
- PagedList
- PagedList.BoundaryCallback
- PagedList.Builder
- PagedList.Callback
- PagedList.Config
- PagedList.Config.Builder
- PagedListAdapter
- PageKeyedDataSource
- PageKeyedDataSource.LoadCallback
- PageKeyedDataSource.LoadInitialCallback
- PageKeyedDataSource.LoadInitialParams
- PageKeyedDataSource.LoadParams
- PositionalDataSource
- PositionalDataSource.LoadInitialCallback
- PositionalDataSource.LoadInitialParams
- PositionalDataSource.LoadRangeCallback
- PositionalDataSource.LoadRangeParams
- RxPagedListBuilder