define(function (require) {
    // List layout
    var layout = require('../../util/layout');
    var formatUtil = require('../../util/format');
    var graphic = require('../../util/graphic');
    function positionGroup(group, model, api) {
        layout.positionGroup(
            group, model.getBoxLayoutParams(),
            {
                width: api.getWidth(),
                height: api.getHeight()
            },
            model.get('padding')
        );
    }
    return {
        /**
         * Layout list like component.
         * It will box layout each items in group of component and then position the whole group in the viewport
         * @param {module:zrender/group/Group} group
         * @param {module:echarts/model/Component} componentModel
         * @param {module:echarts/ExtensionAPI}
         */
        layout: function (group, componentModel, api) {
            var rect = layout.getLayoutRect(componentModel.getBoxLayoutParams(), {
                width: api.getWidth(),
                height: api.getHeight()
            }, componentModel.get('padding'));
            layout.box(
                componentModel.get('orient'),
                group,
                componentModel.get('itemGap'),
                rect.width,
                rect.height
            );
            positionGroup(group, componentModel, api);
        },
        addBackground: function (group, componentModel) {
            var padding = formatUtil.normalizeCssArray(
                componentModel.get('padding')
            );
            var boundingRect = group.getBoundingRect();
            var style = componentModel.getItemStyle(['color', 'opacity']);
            style.fill = componentModel.get('backgroundColor');
            var rect = new graphic.Rect({
                shape: {
                    x: boundingRect.x - padding[3],
                    y: boundingRect.y - padding[0],
                    width: boundingRect.width + padding[1] + padding[3],
                    height: boundingRect.height + padding[0] + padding[2]
                },
                style: style,
                silent: true,
                z2: -1
            });
            graphic.subPixelOptimizeRect(rect);
            group.add(rect);
        }
    };
}); 
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