views: Draw underline in menu bar for accelerators.

atom.gyp

@@ -150,6 +150,8 @@
       'atom/browser/ui/views/global_menu_bar_x11.h',
       'atom/browser/ui/views/menu_bar.cc',
       'atom/browser/ui/views/menu_bar.h',
+      'atom/browser/ui/views/submenu_button.cc',
+      'atom/browser/ui/views/submenu_button.h',
       'atom/browser/ui/views/menu_delegate.cc',
       'atom/browser/ui/views/menu_delegate.h',
       'atom/browser/ui/views/menu_layout.cc',

atom/browser/ui/views/menu_bar.cc

@@ -9,11 +9,9 @@
 #endif
 
 #include "atom/browser/ui/views/menu_delegate.h"
-#include "base/strings/string_util.h"
-#include "base/strings/utf_string_conversions.h"
+#include "atom/browser/ui/views/submenu_button.h"
 #include "ui/base/models/menu_model.h"
 #include "ui/views/background.h"
-#include "ui/views/controls/button/menu_button.h"
 #include "ui/views/layout/box_layout.h"
 
 #if defined(OS_WIN)
@@ -32,13 +30,6 @@ const char kViewClassName[] = "AtomMenuBar";
 // Default color of the menu bar.
 const SkColor kDefaultColor = SkColorSetARGB(255, 233, 233, 233);
 
-// Filter out the "&" in menu label.
-base::string16 FilterMenuButtonLabel(const base::string16& label) {
-  base::string16 out;
-  base::RemoveChars(label, base::ASCIIToUTF16("&").c_str(), &out);
-  return out;
-}
-
 #if defined(USE_X11)
 void GetMenuBarColor(SkColor* enabled, SkColor* disabled, SkColor* highlight,
                      SkColor* hover, SkColor* background) {
@@ -79,8 +70,7 @@ void MenuBar::SetMenu(ui::MenuModel* model) {
   RemoveAllChildViews(true);
 
   for (int i = 0; i < model->GetItemCount(); ++i) {
-    views::MenuButton* button = new views::MenuButton(
-        this, FilterMenuButtonLabel(model->GetLabelAt(i)), this, false);
+    SubmenuButton* button = new SubmenuButton(this, model->GetLabelAt(i), this);
     button->set_tag(i);
 
 #if defined(USE_X11)
@@ -88,6 +78,7 @@ void MenuBar::SetMenu(ui::MenuModel* model) {
     button->SetDisabledColor(disabled_color_);
     button->SetHighlightColor(highlight_color_);
     button->SetHoverColor(hover_color_);
+    button->SetUnderlineColor(enabled_color_);
 #endif
 
     AddChildView(button);

atom/browser/ui/views/submenu_button.cc

@@ -0,0 +1,77 @@
+// Copyright (c) 2014 GitHub, Inc. All rights reserved.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#include "atom/browser/ui/views/submenu_button.h"
+
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/text_utils.h"
+
+namespace atom {
+
+namespace {
+
+// Filter out the "&" in menu label.
+base::string16 FilterAccecelator(const base::string16& label) {
+  base::string16 out;
+  base::RemoveChars(label, base::ASCIIToUTF16("&").c_str(), &out);
+  return out;
+}
+
+}  // namespace
+
+SubmenuButton::SubmenuButton(views::ButtonListener* listener,
+                             const base::string16& title,
+                             views::MenuButtonListener* menu_button_listener)
+    : views::MenuButton(listener, FilterAccecelator(title),
+                        menu_button_listener, false),
+      underline_start_(-1),
+      underline_end_(-1),
+      text_width_(0),
+      text_height_(0),
+      underline_color_(SK_ColorBLACK) {
+  GetUnderlinePosition(title, &underline_start_, &underline_end_);
+  gfx::Canvas::SizeStringInt(text(), font_list(), &text_width_,
+                             &text_height_, 0, 0);
+}
+
+SubmenuButton::~SubmenuButton() {
+}
+
+void SubmenuButton::SetUnderlineColor(SkColor color) {
+  underline_color_ = color;
+}
+
+void SubmenuButton::OnPaint(gfx::Canvas* canvas) {
+  views::MenuButton::OnPaint(canvas);
+
+  if (underline_start_ != underline_end_) {
+    int padding = (width() - text_width_) / 2;
+    int underline_height = (height() + text_height_) / 2 - 2;
+    canvas->DrawLine(gfx::Point(underline_start_ + padding, underline_height),
+                     gfx::Point(underline_end_ + padding, underline_height),
+                     underline_color_);
+  }
+}
+
+void SubmenuButton::GetUnderlinePosition(
+    const base::string16& text, int* start, int* end) {
+  int pos, span;
+  gfx::RemoveAcceleratorChar(text, '&', &pos, &span);
+  if (pos > -1 && span != 0) {
+    GetCharacterPosition(text, pos, start);
+    GetCharacterPosition(text, pos + span, end);
+  }
+}
+
+void SubmenuButton::GetCharacterPosition(
+    const base::string16& text, int index, int* pos) {
+  int width, height;
+  gfx::Canvas::SizeStringInt(text.substr(0, index), font_list(), &width,
+                             &height, 0, 0);
+  *pos = width;
+}
+
+}  // namespace atom

atom/browser/ui/views/submenu_button.h

@@ -0,0 +1,42 @@
+// Copyright (c) 2014 GitHub, Inc. All rights reserved.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#ifndef ATOM_BROWSER_UI_VIEWS_SUBMENU_BUTTON_H_
+#define ATOM_BROWSER_UI_VIEWS_SUBMENU_BUTTON_H_
+
+#include "ui/views/controls/button/menu_button.h"
+
+namespace atom {
+
+// Special button that used by menu bar to show submenus.
+class SubmenuButton : public views::MenuButton {
+ public:
+  SubmenuButton(views::ButtonListener* listener,
+                const base::string16& title,
+                views::MenuButtonListener* menu_button_listener);
+  virtual ~SubmenuButton();
+
+  void SetUnderlineColor(SkColor color);
+
+  // views::MenuButton:
+  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
+
+ private:
+  void GetUnderlinePosition(
+      const base::string16& text, int* start, int* end);
+  void GetCharacterPosition(
+      const base::string16& text, int index, int* pos);
+
+  int underline_start_;
+  int underline_end_;
+  int text_width_;
+  int text_height_;
+  SkColor underline_color_;
+
+  DISALLOW_COPY_AND_ASSIGN(SubmenuButton);
+};
+
+}  // namespace atom
+
+#endif  // ATOM_BROWSER_UI_VIEWS_SUBMENU_BUTTON_H_