[SalesForce] visualforce page pdf record data

I have a visualforce renderas=Pdf, I created a button to save them in notes and attachments related list, this work fine, but I can't get the value record information in my attachment.

If you can help, I appreciate.

public class VFController {

 // Constructor - this only really matters if the autoRun function doesn't work right
     public Opportunity o {get; set;}

    public VFController(ApexPages.StandardController stdController) {
        this.o = (Opportunity)stdController.getRecord();
    }

    // Code we will invoke on page load.
    public PageReference autoRun() {

        String theId = ApexPages.currentPage().getParameters().get('id');

        if (theId == null) {
            // Display the Visualforce page's content if no Id is passed over
            return null;
        }

       list<opportunity> oportunidade = [SELECT id, name, Numero_Sequencial__c FROM Opportunity WHERE id =:theId];

        for (Opportunity o: oportunidade) {
            // Do all the dirty work we need the code to do

       PageReference pdf = Page.Footer_Helitene;
             Attachment attach = new Attachment();
             Blob body;
              try {

        // returns the output of the page as a PDF
        body = pdf.getContentAsPDF();

    // need to pass unit test -- current bug    
    } catch (VisualforceException e) {
        body = Blob.valueOf('Some Text');
    }

    attach.name = o.name+'  '+o.Numero_Sequencial__c+'.pdf' ;
     attach.Body = body;
     attach.ParentId = o.id;
     attach.IsPrivate = false;
     attach.ContentType = 'application/pdf';

     insert attach;

        }

        // Redirect the user back to the original page
        PageReference pageRef = new PageReference('/' + theId);
        pageRef.setRedirect(true);
        return pageRef;
    }
}