I am developing a custom web part in which i have to display data from already
existing link web part. I used an ListViewWebPart for the purpose, in which am
facing some problems.

1) The data of links web part does not get displayed if I give view type as
html. But is rendered correctly if the view type is Chart/Grid.
2) I cannot add the listview webpart to web part collection as the code is
inside another custom web part.

Dim spWebPartCollection As SPWebPartCollection
Dim links_web_part As New ListViewWebPart
Dim guid As Guid
Dim spsite As New SPSite(http://xyz:portNumber)
Dim spweb As SPWeb = spsite.OpenWeb()
Dim splist As SPList = spweb.Lists("links_web_part")
links_web_part.ListName = splist.ID.ToString("B").ToUpper()
spweb = SPControl.GetContextSite(Context).OpenWeb()
links_web_part.ViewGuid = splist.DefaultView.ID.ToString("B").ToUpper()
links_web_part.EnableViewState = True
links_web_part.ViewType = ViewType.Html
links_web_part.RenderControl(output)

Any idea of what the problem can be??? I know for sure that the links are
being retrieved.. but how do I display them in web part?