Materialized font style for TrayItemMore type system tray rows.

ash/common/system/tray/tray_popup_item_style.h

+// Copyright 2016 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 ASH_COMMON_SYSTEM_TRAY_TRAY_POPUP_ITEM_STYLE_H_
+#define ASH_COMMON_SYSTEM_TRAY_TRAY_POPUP_ITEM_STYLE_H_
+
+#include "base/observer_list.h"
+#include "third_party/skia/include/core/SkColor.h"
+
+namespace ui {
+class NativeTheme;
+}  // namespace ui
+
+namespace views {
+class Label;
+}  // namespace views
+
+namespace ash {
+class TrayPopupItemStyleObserver;
+
+// Central style provider for the system tray menu. Makes it easier to ensure
+// all visuals are consistent and easily updated in one spot instead of being
+// defined in multiple places throughout the code.
+class TrayPopupItemStyle {
+ public:
+  // The different visual styles that a row can have.
+  enum class ColorStyle {
+    // Active and clickable.
+    ACTIVE,
+    // Inactive but clickable.
+    INACTIVE,
+    // Disabled and not clickable.
+    DISABLED,
+  };
+
+  // The different font styles that row text can have.
+  enum class FontStyle {
+    // Header rows for default view and detailed view.
+    TITLE,
+    // Main text used by default view rows.
+    DEFAULT_VIEW_LABEL,
+    // Main text used by detailed view rows.
+    DETAILED_VIEW_LABEL,
+    // System information text (e.g. date/time, battery status, etc).
+    SYSTEM_INFO,

[tdanderson, 2016/09/15 19:49:33]

I'm not super excited about the SYSTEM_INFO name since it's very specific. But
it's fine to leave it as-is, it can hopefully evolve into a better name as
various surfaces start using TrayPopupItemStyle.

[bruthig, 2016/09/15 19:55:08]

Acknowledged.

+    // Sub text within a row (e.g. user name in user row).
+    CAPTION,
+    // Child buttons within rows that have a visible border (e.g. "Sign out",
+    // "Lock", Cast's "Stop", etc).

[tdanderson, 2016/09/15 19:49:34]

Sign out / lock are sort of in flux, just use Cast's "Stop" as an example here.

[bruthig, 2016/09/15 21:17:34]

Done.

+    BUTTON,
+  };
+
+  TrayPopupItemStyle(const ui::NativeTheme* theme, FontStyle font_style);
+  ~TrayPopupItemStyle();
+
+  void AddObserver(TrayPopupItemStyleObserver* observer);
+  void RemoveObserver(TrayPopupItemStyleObserver* observer);
+
+  const ui::NativeTheme* theme() const { return theme_; }
+
+  // Sets the |theme_| and notifies observers.
+  void SetTheme(const ui::NativeTheme* theme);
+
+  ColorStyle color_style() const { return color_style_; }

[tdanderson, 2016/09/15 19:49:33]

The member this returns is non-const, so the accessor should also be non-const
(ditto for line 70).

[bruthig, 2016/09/15 21:17:34]

Discussed offline.  Summary: ColorStyle and FontStyle are pod's and thus are
returned by copy.  This means editing them won't update the TrayPopupItemStyle
and wouldn't violate the const declarations here.

+
+  // Sets the |color_style_| and notifies observers if |color_style_| changed.
+  void SetColorStyle(ColorStyle color_style);
+
+  FontStyle font_style() const { return font_style_; }
+
+  // Sets the |font_style_| notifies observers if |font_style_| changed.
+  void SetFontStyle(FontStyle font_style);
+
+  SkColor GetForegroundColor() const;
+
+  // Configures a Label as per the style (e.g. color, font).
+  void SetupLabel(views::Label* label) const;
+
+ private:
+  void NotifyObserversStyleUpdated();
+
+  // The theme that the styles are dervied from.
+  const ui::NativeTheme* theme_;
+
+  FontStyle font_style_;
+
+  ColorStyle color_style_;
+
+  base::ObserverList<TrayPopupItemStyleObserver> observers_;
+};

[tdanderson, 2016/09/15 19:49:34]

DISALLOW_COPY_AND_ASSIGN?

[bruthig, 2016/09/15 21:17:34]

Done.

+
+}  // namespace ash
+
+#endif  // ASH_COMMON_SYSTEM_TRAY_TRAY_POPUP_ITEM_STYLE_H_