gwt - MVP - What adjustment must be made to enable a "UiField FlowPanel" to work (rather than "UiField SimplePanel"? -

I changed my "TopPanel" UiField to FlopNell instead of a SimplePanel.
- But, when I do this, the original "setWidget" method in my "View" category is no longer valid.

What adjustments (- how many can be made) can I compile and process the flopannel "@ UIField" correctly?

Here's the "View" square ...

  Public class TopPanel enhances composite tools AcceptsOneWidget {- - - //...prev ... @Euffield // ... PREVE .. SimplePanel TopPanel; //..Trying to do this work ... @UIFIED FLOPANEL TOPPANEL; - - - // ... Should this method be modified or changed to allow FlopNail "UIField" to work? .... @ Override Public Wide Setview (ISWaid W) {topPanel.setWidget (w); }}   
 This UIBinder template is ...  
  & gt; DOCTYPE UI: UiBinder SYSTEM "http://dl.google.com/gwt/DTD/xhtml.ent" & gt; & Lt; Ui: UiBinder xmlns: ui = "kalash: ui: com.google.gwt.uibinder" xmlns: g = "blur: import: com.google.gwt.user.client.ui" & gt; & Lt; UI: style src = "app.css" /> & Lt; G: HTMLPanel width = "50%" height = "50%" & gt; & Lt ;! - & lt; G: SimplePanel UI: Field = "Toppanel" & gt; - & gt; & Lt; G: FlowPanel UI: field = "toppanel" & gt; & Lt; G: button text = "from AAA: go to BBB" UI: field = "top button A" & gt; & Lt; / G: button & gt; & Lt; G: button text = "bbb: go to ccc" UI: field = "top button" & gt; & Lt; / G: button & gt; & Lt; G: button text = "from ccc: go to aaa" UI: field = "top button c" & gt; & Lt; / G: button & gt; & Lt; / H: FlowPanel & gt; & Lt; / G: HTMLPanel & gt; & Lt; / Ui: UiBinder & gt; Try    
 
 
:  
  topPanel.insert ( Instead of   
,  
  topPanel.setWidget (w)