32 lines
1.2 KiB
JavaScript
32 lines
1.2 KiB
JavaScript
|
import { ImageCache } from 'react-native-img-cache';
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Notifies about the successful download of an <tt>Image</tt> source. The name
|
||
|
|
* is inspired by <tt>Image</tt>. The downloaded <tt>Image</tt> source is not
|
||
|
|
* available because (1) I do not know how to get it from {@link ImageCache} and
|
||
|
|
* (2) we do not need it bellow. The function was explicitly introduced to cut
|
||
|
|
* down on unnecessary <tt>ImageCache</tt> <tt>observer</tt> instances.
|
||
|
|
*
|
||
|
|
* @private
|
||
|
|
* @returns {void}
|
||
|
|
*/
|
||
|
|
function _onLoad() {
|
||
|
|
// ImageCache requires an observer; otherwise, we do not need it because we
|
||
|
|
// merely want to initiate the download and do not care what happens with it
|
||
|
|
// afterwards.
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Initiates the retrieval of a specific <tt>Image</tt> source (if it has not
|
||
|
|
* been initiated already). Due to limitations of {@link ImageCache}, the source
|
||
|
|
* may have at most one <tt>uri</tt>. The name is inspired by <tt>Image</tt>.
|
||
|
|
*
|
||
|
|
* @param {Object} source - The <tt>Image</tt> source with preferably exactly
|
||
|
|
* one <tt>uri</tt>.
|
||
|
|
* @public
|
||
|
|
* @returns {void}
|
||
|
|
*/
|
||
|
|
export function prefetch(source) {
|
||
|
|
ImageCache.get().on(source, /* observer */ _onLoad, /* immutable */ true);
|
||
|
|
}
|