Make info button appear only when mouse is over the panel or the panel has focus.

chrome/browser/ui/panels/panel_browser_frame_view.cc

 // Copyright (c) 2011 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/panels/panel_browser_frame_view.h"
 
 #include "chrome/browser/themes/theme_service.h"
 #include "chrome/browser/ui/panels/panel.h"
 #include "chrome/browser/ui/panels/panel_browser_view.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "grit/app_resources.h"
 #include "grit/generated_resources.h"
 #include "grit/theme_resources.h"
 #include "grit/theme_resources_standard.h"
 #include "third_party/skia/include/effects/SkGradientShader.h"
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas_skia.h"
 #include "views/controls/button/image_button.h"
 #include "views/controls/label.h"
 #include "views/painter.h"
+#include "views/screen.h"
 #include "views/window/window.h"
 #include "views/window/window_shape.h"
 
 #if defined(OS_LINUX)
 #include "views/window/hit_test.h"
 #endif
 
 namespace {
 
 // The height in pixels of the title bar.
@@ skipping 88 matching lines @@
 
   ResourceBundle& rb = ResourceBundle::GetSharedInstance();
   active_font = new gfx::Font(rb.GetFont(ResourceBundle::BoldFont));
   inactive_font = new gfx::Font(rb.GetFont(ResourceBundle::BaseFont));
 
   LoadImageResources();
 }
 
 } // namespace
 
+// PanelBrowserFrameView::MouseWatcher -----------------------------------------
+
+PanelBrowserFrameView::MouseWatcher::MouseWatcher(PanelBrowserFrameView* view)
+    : view_(view),
+      in_view_(false) {
+  MessageLoopForUI::current()->AddObserver(this);
+}
+
+PanelBrowserFrameView::MouseWatcher::~MouseWatcher() {
+  MessageLoopForUI::current()->RemoveObserver(this);
+}
+
+bool PanelBrowserFrameView::MouseWatcher::IsCursorInViewBounds() const {
+  gfx::Point cursor_point = views::Screen::GetCursorScreenPoint();
+  return view_->browser_view_->GetBounds().Contains(cursor_point.x(),
+                                                    cursor_point.y());
+}
+
+#if defined(OS_WIN)
+void PanelBrowserFrameView::MouseWatcher::DidProcessMessage(const MSG& msg) {
+  switch (msg.message) {
+    case WM_MOUSEMOVE:
+    case WM_NCMOUSEMOVE:
+    case WM_MOUSELEAVE:
+    case WM_NCMOUSELEAVE:
+      HandleGlobalMouseMoveEvent();
+      break;
+    default:
+      break;
+  }
+}
+#else
+void PanelBrowserFrameView::MouseWatcher::DidProcessEvent(GdkEvent* event) {
+  switch (event->type) {
+    case GDK_MOTION_NOTIFY:
+    case GDK_LEAVE_NOTIFY:
+      HandleGlobalMouseMoveEvent();
+      break;
+    default:
+      break;
+  }
+}
+#endif
+
+void PanelBrowserFrameView::MouseWatcher::HandleGlobalMouseMoveEvent() {
+  bool in_view = IsCursorInViewBounds();
+  if (in_view == in_view_)
+    return;
+  in_view_ = in_view;
+  view_->OnMouseEnterOrLeaveWindow(in_view_);
+}
+
+// PanelBrowserFrameView -------------------------------------------------------
+
 PanelBrowserFrameView::PanelBrowserFrameView(BrowserFrame* frame,
                                              PanelBrowserView* browser_view)
     : BrowserNonClientFrameView(),
       frame_(frame),
       browser_view_(browser_view),
       paint_state_(NOT_PAINTED),
       info_button_(NULL),
       close_button_(NULL),
       title_icon_(NULL),
       title_label_(NULL) {
   EnsureResourcesInitialized();
   frame_->set_frame_type(views::Window::FRAME_TYPE_FORCE_CUSTOM);
 
   info_button_ = new views::ImageButton(this);
   info_button_->SetImage(views::CustomButton::BS_NORMAL,
                          info_button_resources.normal_image);
   info_button_->SetImage(views::CustomButton::BS_HOT,
                          info_button_resources.hover_image);
   info_button_->SetImage(views::CustomButton::BS_PUSHED,
                          info_button_resources.pushed_image);
   info_button_->SetTooltipText(
       UTF16ToWide(l10n_util::GetStringUTF16(IDS_ACCNAME_ABOUT_PANEL)));
   info_button_->SetAccessibleName(
       l10n_util::GetStringUTF16(IDS_ACCNAME_ABOUT_PANEL));
-  // TODO(jianli): Hide info button by default and show it when mouse is over
-  // panel.
-  // info_button_->SetVisible(false);
+  info_button_->SetVisible(false);
   AddChildView(info_button_);
 
   close_button_ = new views::ImageButton(this);
   close_button_->SetImage(views::CustomButton::BS_NORMAL,
                           close_button_resources.normal_image);
   close_button_->SetImage(views::CustomButton::BS_HOT,
                           close_button_resources.hover_image);
   close_button_->SetImage(views::CustomButton::BS_PUSHED,
                           close_button_resources.pushed_image);
   close_button_->SetTooltipText(
       UTF16ToWide(l10n_util::GetStringUTF16(IDS_TOOLTIP_CLOSE_TAB)));
   close_button_->SetAccessibleName(
       l10n_util::GetStringUTF16(IDS_ACCNAME_CLOSE));
   AddChildView(close_button_);
 
   title_icon_ = new TabIconView(this);
   title_icon_->set_is_light(true);
   AddChildView(title_icon_);
 
   title_label_ = new views::Label(std::wstring());
   title_label_->SetHorizontalAlignment(views::Label::ALIGN_LEFT);
   AddChildView(title_label_);
+
+  mouse_watcher_.reset(new MouseWatcher(this));
 }
 
 PanelBrowserFrameView::~PanelBrowserFrameView() {
 }
 
 gfx::Rect PanelBrowserFrameView::GetBoundsForTabStrip(
     views::View* tabstrip) const {
   // Panels never show a tab strip.
   NOTREACHED();
   return gfx::Rect();
@@ skipping 281 matching lines @@
       client_view_bounds_.x() - client_edges.left->width(),
       client_area_top, client_edges.left->width(), client_area_height);
 }
 
 void PanelBrowserFrameView::UpdateTitleBar() {
   title_label_->SetText(
       frame_->window_delegate()->GetWindowTitle());
 }
 
 void PanelBrowserFrameView::OnActivationChanged(bool active) {
+  UpdateInfoButtonVisibility(active, mouse_watcher_->IsCursorInViewBounds());
   SchedulePaint();
 }
+
+void PanelBrowserFrameView::OnMouseEnterOrLeaveWindow(bool mouse_entered) {
+  UpdateInfoButtonVisibility(browser_view_->panel()->IsActive(),
+                             mouse_entered);
+}
+
+void PanelBrowserFrameView::UpdateInfoButtonVisibility(bool active,
+                                                       bool cursor_in_view) {
+  info_button_->SetVisible(active || cursor_in_view);
+}