function createWechat (elem, data) {
        var wechat = getElementsByClassName(elem, 'icon-wechat', 'a');

        if (wechat.length === 0) {
            return false;
        }

        var elems = createElementByString('<div class="wechat-qrcode"><h4>' + data.wechatQrcodeTitle + '</h4><div class="qrcode"></div><div class="help">' + data.wechatQrcodeHelper + '</div></div>');
        var qrcode = getElementsByClassName(elems[0], 'qrcode', 'div');

        new QRCode(qrcode[0], {text: data.url, width: data.wechatQrcodeSize, height: data.wechatQrcodeSize});
        wechat[0].appendChild(elems[0]);
    }
Create the wechat icon and QRCode.

@param {Element} elem
@param {Object} data