OAF pageContext.getParameter("View"); return Null when HTML page is loaded

We are using EBS 12.2.11

I need to change the OAF Page where clause based on the LOV selected on the page.

In the controller file I am able to do this when the LOV is changed and the Go button is pressed I can update the where clause and the data returned is correct

sample of controller code

"

String s_view = pageContext.getParameter("View");

        pageContext.writeDiagnostics (this, "s_view = " + s_view, 1);

        if (pageContext.getParameter("Go") != null) {

          pageContext.writeDiagnostics (this, "user pressed the go button", 1);

           if (s_view.equals("6")) {

            pageContext.writeDiagnostics (this, "user selected the My Department Work option", 1);

            OAApplicationModule am = (OAApplicationModule) pageContext.getApplicationModule(webBean);