How to get string from page in webView

I would like to get some values from an opened page in WebView, this link is a sample of page, I would like of the values of Codigo and Total: http://nfe.sefaz.ba.gov.br/servicos/nfce/modulos/geral/NFCEC_consulta_chave_acesso.aspx?p=29200475315333007383655020002774691048579177|2|1|1|0FD0E1BAD2B244C714075C29FF67C0C012297E1B