Change IFWL_Widget to store a single delegate.

xfa/fxfa/app/cxfa_fffielddelegate.cpp

+// Copyright 2016 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "xfa/fxfa/app/cxfa_fffielddelegate.h"
+
+#include "xfa/fxfa/cxfa_eventparam.h"
+
+CXFA_FFFieldDelegate::CXFA_FFFieldDelegate(
+    std::unique_ptr<IFWL_WidgetDelegate> pDelegate,
+    CXFA_FFField* pWidget)
+    : m_pDelegate(std::move(pDelegate)), m_pWidget(pWidget) {}
+
+CXFA_FFFieldDelegate::~CXFA_FFFieldDelegate() {}
+
+void CXFA_FFFieldDelegate::OnProcessMessage(CFWL_Message* pMessage) {}
+
+void CXFA_FFFieldDelegate::OnProcessEvent(CFWL_Event* pEvent) {
+  switch (pEvent->GetClassID()) {
+    case CFWL_EventType::Mouse: {
+      CFWL_EvtMouse* event = static_cast<CFWL_EvtMouse*>(pEvent);
+      if (event->m_dwCmd == FWL_MouseCommand::Enter) {
+        CXFA_EventParam eParam;
+        eParam.m_eType = XFA_EVENT_MouseEnter;
+        eParam.m_pTarget = m_pWidget->GetDataAcc();
+        m_pWidget->GetDataAcc()->ProcessEvent(XFA_ATTRIBUTEENUM_MouseEnter,
+                                              &eParam);
+      } else if (event->m_dwCmd == FWL_MouseCommand::Leave) {
+        CXFA_EventParam eParam;
+        eParam.m_eType = XFA_EVENT_MouseExit;
+        eParam.m_pTarget = m_pWidget->GetDataAcc();
+        m_pWidget->GetDataAcc()->ProcessEvent(XFA_ATTRIBUTEENUM_MouseExit,
+                                              &eParam);
+      } else if (event->m_dwCmd == FWL_MouseCommand::LeftButtonDown) {
+        CXFA_EventParam eParam;
+        eParam.m_eType = XFA_EVENT_MouseDown;
+        eParam.m_pTarget = m_pWidget->GetDataAcc();
+        m_pWidget->GetDataAcc()->ProcessEvent(XFA_ATTRIBUTEENUM_MouseDown,
+                                              &eParam);
+      } else if (event->m_dwCmd == FWL_MouseCommand::LeftButtonUp) {
+        CXFA_EventParam eParam;
+        eParam.m_eType = XFA_EVENT_MouseUp;
+        eParam.m_pTarget = m_pWidget->GetDataAcc();
+        m_pWidget->GetDataAcc()->ProcessEvent(XFA_ATTRIBUTEENUM_MouseUp,
+                                              &eParam);
+      }
+      break;
+    }
+    case CFWL_EventType::Click: {
+      CXFA_EventParam eParam;
+      eParam.m_eType = XFA_EVENT_Click;
+      eParam.m_pTarget = m_pWidget->GetDataAcc();
+      m_pWidget->GetDataAcc()->ProcessEvent(XFA_ATTRIBUTEENUM_Click, &eParam);
+      break;
+    }
+    default:
+      break;
+  }
+}
+
+void CXFA_FFFieldDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                        const CFX_Matrix* pMatrix) {}