Support dragging panels to stack and snap.

chrome/browser/ui/views/panels/panel_view.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/ui/views/panels/panel_view.h"
 
 #include <map>
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/panels/panel.h"
 #include "chrome/browser/ui/panels/panel_bounds_animation.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
+#include "chrome/browser/ui/panels/stacked_panel_collection.h"
 #include "chrome/browser/ui/views/panels/panel_frame_view.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/path.h"
 #include "ui/gfx/screen.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/webview/webview.h"
@@ skipping 549 matching lines @@
     const gfx::Size& window_size) const {
   gfx::Size frame = GetFrameView()->NonClientAreaSize();
   return gfx::Size(window_size.width() - frame.width(),
                    window_size.height() - frame.height());
 }
 
 int PanelView::TitleOnlyHeight() const {
   return panel::kTitlebarHeight;
 }
 
+void PanelView::UpdatePanelStackingProperty() {
+#if defined(OS_WIN) && !defined(USE_AURA)
+  StackedPanelCollection* stack = NULL;
+  if (panel_->collection()->type() == PanelCollection::STACKED)
+    stack = static_cast<StackedPanelCollection*>(panel_->collection());
+  HWND owner = stack ? stack->GetNativeWindow() : NULL;
+  if (owner)
+    UpdateWindowAttribute(GWL_EXSTYLE, 0, WS_EX_APPWINDOW, false);

[Dmitry Titov, 2013/01/09 02:29:50]

Please add a comment here, to explain why this is done.

[jianli, 2013/01/09 21:00:59]

Done.

+  else
+    UpdateWindowAttribute(GWL_EXSTYLE, WS_EX_APPWINDOW, 0, false);
+  ::SetWindowLong(GetNativePanelHandle(),
+                  GWL_HWNDPARENT,
+                  reinterpret_cast<LONG>(owner));
+#else
+  NOTIMPLEMENTED();
+#endif
+}
+
 void PanelView::AttachWebContents(content::WebContents* contents) {
   web_view_->SetWebContents(contents);
 }
 
 void PanelView::DetachWebContents(content::WebContents* contents) {
   web_view_->SetWebContents(NULL);
 }
 
 NativePanelTesting* PanelView::CreateNativePanelTesting() {
   return new NativePanelTestingWin(this);
@@ skipping 327 matching lines @@
   DCHECK(thickness_for_mouse_resizing > 0);
   SkRegion* region = new SkRegion;
   region->op(0, 0, thickness_for_mouse_resizing, height, SkRegion::kUnion_Op);
   region->op(width - thickness_for_mouse_resizing, 0, width, height,
       SkRegion::kUnion_Op);
   region->op(0, height - thickness_for_mouse_resizing, width, height,
       SkRegion::kUnion_Op);
   web_contents->GetRenderViewHost()->GetView()->SetClickthroughRegion(region);
 #endif
 }