Overview

The callback that links AsyncListUtil with the list view.

All methods are called on the main thread.

Summary

Fields

No scroll direction hint available.

Scrolling in descending order (from higher to lower positions in the order of the backing storage).

Scrolling in ascending order (from lower to higher positions in the order of the backing storage).

Constructors

Methods

Compute the range of visible item positions.

outRange[0] is the position of the first visible item (in the order of the backing storage).

outRange[1] is the position of the last visible item (in the order of the backing storage).

Negative positions and positions greater or equal to AsyncListUtil.getItemCount() are invalid. If the returned range contains invalid positions it is ignored (no item will be loaded).

Parameters:

outRange: The visible item range.

Compute a wider range of items that will be loaded for smoother scrolling.

If there is no scroll hint, the default implementation extends the visible range by half its length in both directions. If there is a scroll hint, the range is extended by its full length in the scroll direction, and by half in the other direction.

For example, if range is {100, 200} and scrollHint is AsyncListUtil.ViewCallback.HINT_SCROLL_ASC, then outRange will be {50, 300}.

However, if scrollHint is AsyncListUtil.ViewCallback.HINT_SCROLL_NONE, then outRange will be {50, 250}

Parameters:

range: Visible item range.
outRange: Extended range.
scrollHint: The scroll direction hint.

Called when the entire data set has changed.

Called when an item at the given position is loaded.

Parameters:

position: Item position.