var items = [];
var columns = [0, 0]; // 设定分两列
var flattenEntry = this.model.flattenEntry.slice(0); // 获取扁平化为两层的目录
var entry = {};
while (flattenEntry.length > 0) {
    entry = flattenEntry.shift();
    if (columns[0] > columns[1]) {
        items.push({
            el: {
                type: "目录区块"
            },
            left: "50%", right: 0,
            top: columns[1]
        });
        columns[1] += 目录区块高度;
    } else {
        items.push({
            el: {
                type: "目录区块"
            },
            left: 0, right: "50%",
            top: columns[0]
        });
        columns[0] += 区块高度;
    }
}

return {
    type: "bi.absolute",
    items: items
};