Preview CL for adding an Infobar facility to Google Chrome Frame....

chrome_frame/infobar_manager.h

+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// @file
+// Manager for infobar windows.
+
+#ifndef CHROME_FRAME_INFOBAR_MANAGER_H_
+#define CHROME_FRAME_INFOBAR_MANAGER_H_
+
+#include "base/scoped_ptr.h"
+#include "base/singleton.h"
+#include "base/task_queue.h"
+#include "chrome_frame/infobar_window.h"
+
+// InfobarManager creates and manages infobars, which are displayed at the top
+// or bottom of IE content window.
+class InfobarManager {
+ public:
+  class DisplacedWindowManager;
+
+  // Constructs an InfobarManager for the specified browser (IE6) or browser
+  // tab (IE7+).
+  //
+  // At most one InfobarManager should be constructed per tab or browser.
+  explicit InfobarManager(HWND tab_window);
+
+  // Shows the supplied content in an infobar of the specified type.
+  // Normally, content->InstallInFrame will be called with an interface the
+  // content may use to interact with the Infobar facility.
+  //
+  // IFF Show() returns success, content->Reset() is guaranteed to be called
+  // when the Infobar is no longer visible. The InfobarContent implementation is
+  // responsible for freeing itself and its resources at any time during or
+  // after the call to Reset().
+  HRESULT Show(InfobarContent *content, InfobarType type, int max_height);
+  // Hides the infobar of the specified type.
+  HRESULT Hide(InfobarType type);
+  // Hides all infobars.
+  void HideAll();
+
+ private:
+  // This callback class encapsulates the communication between InfobarWindow
+  // instances and the InfobarManager.
+  class InfobarHostImpl : public InfobarWindow::InfobarHost {
+   public:
+    InfobarHostImpl(InfobarManager *manager);
+    // Implementation of InfobarWindow::InfobarHost.
+    virtual HWND GetContainerWindow();
+    virtual bool UpdateLayout();
+   private:
+    // Not owned by this instance.
+    InfobarManager *manager_;
+  };
+
+  friend class InfobarHostImpl;
+  friend class DisplacedWindowManager;
+
+  // Finds the window to be displaced and instantiate a DisplacedWindowManager
+  // for it if one does not already exist. Returns true if there is a valid
+  // DisplacedWindowManager instance at the end of the call.
+  bool FindDisplacedWindow();
+
+  // These functions are called by the InfobarHostImpl
+  //
+  // Causes a (deferred) re-layout of the Infobars. ReserveSpace will be invoked
+  // on each InfobarWindow instance and the on-screen dimensions of the
+  // displaced window updated accordingly. Returns true if successful, in which
+  // case either a subsequent Hide() or ReserveSpace() is guaranteed.
+  bool UpdateLayout();
+  
+  // Receive notifications from DisplacedWindowManager
+  void AdjustDisplacedWindowDimensions(RECT* rect);
+  void OnDisplacedWindowDestroyed();
+
+  // Delegate for InfobarWindow
+  InfobarHostImpl infobar_host_impl_;
+  // The HWND of the tab window the infobars are associated with.
+  HWND container_window_;
+  // Subclasses and observes changes to the displaced window.
+  DisplacedWindowManager* displaced_window_manager_;
+  // Infobar windows.
+  scoped_ptr<InfobarWindow> infobars_[END_OF_INFOBAR_TYPE];
+
+  DISALLOW_COPY_AND_ASSIGN(InfobarManager);
+};
+
+#endif  // CHROME_FRAME_INFOBAR_MANAGER_H_