How to call SOAP Web Services from Ionic with Complex Parameters

Hi,
I want to call a SOAP Web Service from an ionic app. I saw a nice article by Andrew Mcgivery http://mcgivery.com/soap-web-services-angular-ionic/ @andrewmcgivery

But, it deals with basic xml request. What about when the request is a tree like XML.
The below XML Request works perfectly in SOAPUI.
How to achieve it in inside an Ionic App.

 var sr = '<?xml version="1.0" encoding="utf-8"?>' 
         +'<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:urn="urn:NAMESPACE:7:0">'
         +'<soapenv:Header/>'
         +'<soapenv:Body>'
          +'<urn:FindCertificatesRequest>'
           +'<urn:CertificateSearch>'
            +'<urn:MainDivision>'
             +'<urn:IsoAlphaCountryCode>USA</urn:IsoAlphaCountryCode>'
            +'</urn:MainDivision>'
           +'<urn:Taxpayer>'
             +'<urn:CompanyCode>XXXX</urn:CompanyCode>'
             +'<urn:DivisionCode>XXXX</urn:DivisionCode>'
           +'</urn:Taxpayer>'
           +'<urn:CustomerCode>XXXXXX</urn:CustomerCode>'
           +'<urn:TransactionType>XXXX</urn:TransactionType>'
           +'<urn:CertificateScope>XXXX</urn:CertificateScope>'
          +'</urn:CertificateSearch>'
         +'<urn:SystemContext>'
           +'<urn:Login>'
             +'<urn:UserName>XXXX</urn:UserName>'
             +'<urn:Password>XXXX</urn:Password>'
           +'</urn:Login>'
          +'<urn:AsOfDate>XXXXXX</urn:AsOfDate>'
          +'<urn:Perspective>XXXX</urn:Perspective>'
          +'<urn:MaximumSearchResults>100</urn:MaximumSearchResults>'
         +'</urn:SystemContext>'
        +'</urn:FindCertificatesRequest>'
       +'</soapenv:Body>'
      +'</soapenv:Envelope>';