# ItemKeyedDataSource.LoadInitialCallback

Summary:[Ctors](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback#pubctors)\|[Methods](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback#pubmethods)\|[Inherited Methods](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback#inhmethods)  

# ItemKeyedDataSource.LoadInitialCallback

| The`android.arch`Architecture Components packages are no longer maintained. They have been superseded by the corresponding[androidx.\*](https://developer.android.com/jetpack/androidx/migrate)packages. See[androidx.paging.ItemKeyedDataSource.LoadInitialCallback](https://developer.android.com/reference/androidx/paging/ItemKeyedDataSource.LoadInitialCallback)instead.

`
public
static

abstract
class
ItemKeyedDataSource.LoadInitialCallback
`  
`


``

extends `[LoadCallback](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadCallback)`<Value>


``


`

|---|---|----------------------------------------------------------------------|
| java.lang.Object                                                           |||
| ↳ | [android.arch.paging.ItemKeyedDataSource.LoadCallback](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadCallback)\<Value\> ||
|   | ↳ | android.arch.paging.ItemKeyedDataSource.LoadInitialCallback\<Value\> |

<br />

*** ** * ** ***

Callback for[loadInitial(LoadInitialParams, LoadInitialCallback)](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource#loadInitial(android.arch.paging.ItemKeyedDataSource.LoadInitialParams<Key>, android.arch.paging.ItemKeyedDataSource.LoadInitialCallback<Value>))to return data and, optionally, position/count information.

A callback can be called only once, and will throw if called again.

If you can compute the number of items in the data set before and after the loaded range, call the three parameter[onResult(List, int, int)](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback#onResult(java.util.List<Value>, int, int))to pass that information. You can skip passing this information by calling the single parameter[onResult(List)](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadCallback#onResult(java.util.List<Value>)), either if it's difficult to compute, or if[placeholdersEnabled](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialParams#placeholdersEnabled)is`false`, so the positioning information will be ignored.

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                                                                                       ||
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---|
| ` `[ItemKeyedDataSource.LoadInitialCallback](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback#ItemKeyedDataSource.LoadInitialCallback())`() ` |

|                                                                                                                                   ### Public methods                                                                                                                                   ||
|------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| ` abstract void` | ` `[onResult](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback#onResult(java.util.List<Value>, int, int))`(List<Value> data, int position, int totalCount) ` Called to pass initial load state from a DataSource. |

| ### Inherited methods |
|-----------------------|---|
| From class` `[android.arch.paging.ItemKeyedDataSource.LoadCallback](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadCallback)` ` |------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` abstract void` | ` `[onResult](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadCallback#onResult(java.util.List<Value>))`(List<Value> data) ` Called to pass loaded data from a DataSource. | ||
| From class` java.lang.Object ` |-------------------|-------------------------------| | ` Object`         | ` clone() `                   | | ` boolean`        | ` equals(Object arg0) `       | | ` void`           | ` finalize() `                | | ` final Class<?>` | ` getClass() `                | | ` int`            | ` hashCode() `                | | ` final void`     | ` notify() `                  | | ` final void`     | ` notifyAll() `               | | ` String`         | ` toString() `                | | ` final void`     | ` wait(long arg0, int arg1) ` | | ` final void`     | ` wait(long arg0) `           | | ` final void`     | ` wait() `                    | ||

## Public constructors

### ItemKeyedDataSource.LoadInitialCallback

```
ItemKeyedDataSource.LoadInitialCallback ()
```

<br />

<br />

## Public methods

### onResult

```
void onResult (List<Value> 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 data back through this method.

It is always valid to pass a different amount of data than what is requested. Pass an empty list if there is no more data to load.

<br />

|                                                                                                     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. <br />                                                       |
| `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`. <br />                                          |
| `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`. <br /> |

-

  ## Interfaces

  - [DataSource.InvalidatedCallback](https://developer.android.com/reference/android/arch/paging/DataSource.InvalidatedCallback)
-

  ## Classes

  - [AsyncPagedListDiffer](https://developer.android.com/reference/android/arch/paging/AsyncPagedListDiffer)
  - [DataSource](https://developer.android.com/reference/android/arch/paging/DataSource)
  - [DataSource.Factory](https://developer.android.com/reference/android/arch/paging/DataSource.Factory)
  - [ItemKeyedDataSource](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource)
  - [ItemKeyedDataSource.LoadCallback](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadCallback)
  - [ItemKeyedDataSource.LoadInitialCallback](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialCallback)
  - [ItemKeyedDataSource.LoadInitialParams](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadInitialParams)
  - [ItemKeyedDataSource.LoadParams](https://developer.android.com/reference/android/arch/paging/ItemKeyedDataSource.LoadParams)
  - [LivePagedListBuilder](https://developer.android.com/reference/android/arch/paging/LivePagedListBuilder)
  - [PagedList](https://developer.android.com/reference/android/arch/paging/PagedList)
  - [PagedList.BoundaryCallback](https://developer.android.com/reference/android/arch/paging/PagedList.BoundaryCallback)
  - [PagedList.Builder](https://developer.android.com/reference/android/arch/paging/PagedList.Builder)
  - [PagedList.Callback](https://developer.android.com/reference/android/arch/paging/PagedList.Callback)
  - [PagedList.Config](https://developer.android.com/reference/android/arch/paging/PagedList.Config)
  - [PagedList.Config.Builder](https://developer.android.com/reference/android/arch/paging/PagedList.Config.Builder)
  - [PagedListAdapter](https://developer.android.com/reference/android/arch/paging/PagedListAdapter)
  - [PageKeyedDataSource](https://developer.android.com/reference/android/arch/paging/PageKeyedDataSource)
  - [PageKeyedDataSource.LoadCallback](https://developer.android.com/reference/android/arch/paging/PageKeyedDataSource.LoadCallback)
  - [PageKeyedDataSource.LoadInitialCallback](https://developer.android.com/reference/android/arch/paging/PageKeyedDataSource.LoadInitialCallback)
  - [PageKeyedDataSource.LoadInitialParams](https://developer.android.com/reference/android/arch/paging/PageKeyedDataSource.LoadInitialParams)
  - [PageKeyedDataSource.LoadParams](https://developer.android.com/reference/android/arch/paging/PageKeyedDataSource.LoadParams)
  - [PositionalDataSource](https://developer.android.com/reference/android/arch/paging/PositionalDataSource)
  - [PositionalDataSource.LoadInitialCallback](https://developer.android.com/reference/android/arch/paging/PositionalDataSource.LoadInitialCallback)
  - [PositionalDataSource.LoadInitialParams](https://developer.android.com/reference/android/arch/paging/PositionalDataSource.LoadInitialParams)
  - [PositionalDataSource.LoadRangeCallback](https://developer.android.com/reference/android/arch/paging/PositionalDataSource.LoadRangeCallback)
  - [PositionalDataSource.LoadRangeParams](https://developer.android.com/reference/android/arch/paging/PositionalDataSource.LoadRangeParams)
  - [RxPagedListBuilder](https://developer.android.com/reference/android/arch/paging/RxPagedListBuilder)