@wezom/zz-load/dist/loads/source-img.js

Lazy loader based on IntersectionObserver API

import attrs from '../config/attrs';
export default function (element, resource, _a, loadActions, errorActions) {
	var setSourcesOnlyOnLoad = _a.setSourcesOnlyOnLoad;
	var srcset = element.getAttribute(attrs.sourceSrcSet);
	if (setSourcesOnlyOnLoad) {
		var img = document.createElement('img');
		img.addEventListener('error', function (event) {
			return errorActions(event, resource);
		});
		img.addEventListener('load', function (event) {
			if (srcset) {
				element.srcset = srcset;
			}
			element.src = resource;
			loadActions(event, resource);
		});
		if (srcset) {
			img.srcset = srcset;
		}
		img.src = resource;
	} else {
		element.addEventListener('error', function (event) {
			return errorActions(event, resource);
		});
		element.addEventListener(
			'load',
			function (event) {
				loadActions(event, resource);
			},
			{
				once: true
			}
		);
		if (srcset) {
			element.srcset = srcset;
		}
		element.src = resource;
	}
}