fpdfsdk/ differences with XFA (for didactic purposes only).

fpdfsdk/include/formfiller/FFL_IFormFiller.h

Index: fpdfsdk/include/formfiller/FFL_IFormFiller.h
diff --git a/fpdfsdk/include/formfiller/FFL_IFormFiller.h b/fpdfsdk/include/formfiller/FFL_IFormFiller.h
index 3eb4a4689a0aa7d94db9de7a8c2eb65e5bc76117..bfdce10f594d6825cb288305b0cb9f79b33761e7 100644
--- a/fpdfsdk/include/formfiller/FFL_IFormFiller.h
+++ b/fpdfsdk/include/formfiller/FFL_IFormFiller.h
@@ -112,6 +112,28 @@ class CFFL_IFormFiller : public IPWL_Filler_Notify {
                   FX_BOOL& bReset,
                   FX_BOOL& bExit,
                   FX_UINT nFlag);
+#ifdef PDF_ENABLE_XFA
+  void OnClick(CPDFSDK_Widget* pWidget,
+               CPDFSDK_PageView* pPageView,
+               FX_BOOL& bReset,
+               FX_BOOL& bExit,
+               FX_UINT nFlag);
+  void OnFull(CPDFSDK_Widget* pWidget,
+              CPDFSDK_PageView* pPageView,
+              FX_BOOL& bReset,
+              FX_BOOL& bExit,
+              FX_UINT nFlag);
+  void OnPreOpen(CPDFSDK_Widget* pWidget,
+                 CPDFSDK_PageView* pPageView,
+                 FX_BOOL& bReset,
+                 FX_BOOL& bExit,
+                 FX_UINT nFlag);
+  void OnPostOpen(CPDFSDK_Widget* pWidget,
+                  CPDFSDK_PageView* pPageView,
+                  FX_BOOL& bReset,
+                  FX_BOOL& bExit,
+                  FX_UINT nFlag);
+#endif
 
  private:
   using CFFL_Widget2Filler = std::map<CPDFSDK_Annot*, CFFL_FormFiller*>;
@@ -131,8 +153,21 @@ class CFFL_IFormFiller : public IPWL_Filler_Notify {
                          FX_BOOL& bRC,
                          FX_BOOL& bExit,
                          FX_DWORD nFlag) override;
+#ifdef PDF_ENABLE_XFA
+  void OnPopupPreOpen(void* pPrivateData,
+                      FX_BOOL& bExit,
+                      FX_DWORD nFlag) override;
+  void OnPopupPostOpen(void* pPrivateData,
+                       FX_BOOL& bExit,
+                       FX_DWORD nFlag) override;
+#endif
 
   void UnRegisterFormFiller(CPDFSDK_Annot* pAnnot);
+#ifdef PDF_ENABLE_XFA
+  void SetFocusAnnotTab(CPDFSDK_Annot* pWidget,
+                        FX_BOOL bSameField,
+                        FX_BOOL bNext);
+#endif
 
   CPDFDoc_Environment* m_pApp;
   CFFL_Widget2Filler m_Maps;