Package com.bumptech.glide

Class ListPreloader<T>

java.lang.Object

com.bumptech.glide.ListPreloader<T>

Type Parameters:

T - The type of the model being displayed in the list.

All Implemented Interfaces:

AbsListView.OnScrollListener

public class ListPreloader<T>
extends Object
implements AbsListView.OnScrollListener

Loads a few resources ahead in the direction of scrolling in any AbsListView so that images are in the memory cache just before the corresponding view in created in the list. Gives the appearance of an infinitely large image cache, depending on scrolling speed, cpu speed, and cache size.

Must be put using AbsListView.setOnScrollListener(android.widget.AbsListView.OnScrollListener), or have its corresponding methods called from another AbsListView.OnScrollListener to function.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ListPreloader.PreloadModelProvider<U>	An implementation of PreloadModelProvider should provide all the models that should be preloaded.
static interface	ListPreloader.PreloadSizeProvider<T>	An implementation of PreloadSizeProvider should provide the size of the view in the list where the resources will be displayed.

Field Summary

Fields inherited from interface android.widget.AbsListView.OnScrollListener

SCROLL_STATE_FLING, SCROLL_STATE_IDLE, SCROLL_STATE_TOUCH_SCROLL

Constructor Summary

Constructors

Constructor	Description
ListPreloader(RequestManager requestManager, ListPreloader.PreloadModelProvider<T> preloadModelProvider, ListPreloader.PreloadSizeProvider<T> preloadDimensionProvider, int maxPreload)	Constructor for ListPreloader that accepts interfaces for providing the dimensions of images to preload, the list of models to preload for a given position, and the request to use to load images.

Method Summary

Modifier and Type	Method	Description
void	onScroll(AbsListView absListView, int firstVisible, int visibleCount, int totalCount)
void	onScrollStateChanged(AbsListView absListView, int scrollState)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ListPreloader

public ListPreloader(@NonNull
 RequestManager requestManager,
 @NonNull
 ListPreloader.PreloadModelProvider<T> preloadModelProvider,
 @NonNull
 ListPreloader.PreloadSizeProvider<T> preloadDimensionProvider,
 int maxPreload)

Constructor for ListPreloader that accepts interfaces for providing the dimensions of images to preload, the list of models to preload for a given position, and the request to use to load images.

Parameters:

preloadModelProvider - Provides models to load and requests capable of loading them.

preloadDimensionProvider - Provides the dimensions of images to load.

maxPreload - Maximum number of items to preload.

Method Details

onScrollStateChanged

public void onScrollStateChanged(AbsListView absListView,
 int scrollState)

Specified by:

onScrollStateChanged in interface AbsListView.OnScrollListener

onScroll

public void onScroll(AbsListView absListView,
 int firstVisible,
 int visibleCount,
 int totalCount)

Specified by:

onScroll in interface AbsListView.OnScrollListener