Factor out window creation into base::WindowImpl. This class will be used in...

base/window_impl.h

+// Copyright (c) 2009 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.
+
+#ifndef BASE_WINDOW_IMPL_H_
+#define BASE_WINDOW_IMPL_H_
+
+#include <atlbase.h>
+#include <atlapp.h>
+#include <atlmisc.h>
+#include <atlcrack.h>
+
+#include <string>
+
+#include "base/gfx/native_widget_types.h"
+#include "base/gfx/rect.h"
+#include "base/logging.h"
+
+namespace base {
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// WindowImpl
+//  A convenience class that encapsulates the details of creating and
+//  destroying a HWND.  This class also hosts the windows procedure used by all
+//  Windows.
+//
+///////////////////////////////////////////////////////////////////////////////
+class WindowImpl {
+ public:
+  WindowImpl();
+  virtual ~WindowImpl();
+
+  BEGIN_MSG_MAP_EX(WidgetWin)
+    // No messages to handle
+  END_MSG_MAP()
+
+  // Initialize the Window with a parent and an initial desired size.
+  virtual void Init(HWND parent, const gfx::Rect& bounds);
+
+  // Returns the gfx::NativeView associated with this Window.
+  virtual gfx::NativeView GetNativeView() const;
+
+  // Retrieves the default window icon to use for windows if none is specified.
+  virtual HICON GetDefaultWindowIcon() const;
+
+  // Sets the window styles. This is ONLY used when the window is created.
+  // In other words, if you invoke this after invoking Init, nothing happens.
+  void set_window_style(DWORD style) { window_style_ = style; }
+  DWORD window_style() const { return window_style_; }
+
+  // Sets the extended window styles. See comment about |set_window_style|.
+  void set_window_ex_style(DWORD style) { window_ex_style_ = style; }
+  DWORD window_ex_style() const { return window_ex_style_; }
+
+  // Sets the class style to use. The default is CS_DBLCLKS.
+  void set_initial_class_style(UINT class_style) {
+    // We dynamically generate the class name, so don't register it globally!
+    DCHECK_EQ((class_style & CS_GLOBALCLASS), 0);
+    class_style_ = class_style;
+  }
+  UINT initial_class_style() { return class_style_; }
+
+ protected:
+  // Call close instead of this to Destroy the window.
+  BOOL DestroyWindow();
+
+  // Handles the WndProc callback for this object.
+  virtual LRESULT OnWndProc(UINT message, WPARAM w_param, LPARAM l_param);
+
+ private:
+  friend class ClassRegistrar;
+
+  // The windows procedure used by all Windows.
+  static LRESULT CALLBACK WndProc(HWND window,
+                                  UINT message,
+                                  WPARAM w_param,
+                                  LPARAM l_param);
+
+  // Gets the window class name to use when creating the corresponding HWND.
+  // If necessary, this registers the window class.
+  std::wstring GetWindowClassName();
+
+  // All classes registered by WidgetWin start with this name.
+  static const wchar_t* const kBaseClassName;
+
+  // Window Styles used when creating the window.
+  DWORD window_style_;
+
+  // Window Extended Styles used when creating the window.
+  DWORD window_ex_style_;
+
+  // Style of the class to use.
+  UINT class_style_;
+
+  // Our hwnd.
+  HWND hwnd_;
+
+  DISALLOW_COPY_AND_ASSIGN(WindowImpl);
+};
+
+}  // namespace base
+
+#endif  // BASE_WINDOW_IMPL_H_