Step 1 in refactoring NativeThemeWin so that it shares more with the native

theme support in linux and chromeos.

This first change introduces a new common base class for all plaforms called
NativeTheme, and NativeThemeWin now derives from it.  NativeThemeWin will
continue to support its "old" API while the transition to the new API is
ongoing, so that each user of NativeThemeWin can be transitioned carefully.

Once the windows support is complete, the linux and chromeos native themes
will then derive from NativeTheme, and any references do the specific platform
classes will be removed as needed.

TEST=No user visible changes caused by this CL
BUG=None
R=xiyuan@chromium.org

Review URL: http://codereview.chromium.org/6728029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@80314 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 164 insertions, 0 deletions

diff --git a/ui/gfx/native_theme.h b/ui/gfx/native_theme.h
new file mode 100644
index 0000000..807427d
--- /dev/null
+++ b/ui/gfx/native_theme.h
@@ -0,0 +1,164 @@
+// 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.
+
+#ifndef UI_GFX_NATIVE_THEME_H_
+#define UI_GFX_NATIVE_THEME_H_
+#pragma once
+
+#include "skia/ext/platform_canvas.h"
+#include "ui/gfx/native_widget_types.h"
+
+namespace skia {
+class PlatformCanvas;
+}
+
+namespace gfx {
+
+class Rect;
+class Size;
+
+// This class supports drawing UI controls (like buttons, text fields, lists,
+// comboboxes, etc) that look like the native UI controls of the underlying
+// platform, such as Windows or Linux.
+//
+// The supported control types are listed in the Part enum.  These parts can be
+// in any state given by the State enum, where the actual definititon of the
+// state is part-specific.
+//
+// Some parts require more information than simply the state in order to be
+// drawn correctly, and this information is given to the Paint() method via the
+// ExtraParams union.  Each part that requires more information has its own
+// field in the union.
+//
+// NativeTheme also supports getting the default size of a given part with
+// the GetPartSize() method.
+class NativeTheme {
+ public:
+  // The part to be painted / sized.
+  enum Part {
+    kScrollbarDownArrow,
+    kScrollbarLeftArrow,
+    kScrollbarRightArrow,
+    kScrollbarUpArrow,
+    kScrollbarHorizontalThumb,
+    kScrollbarVerticalThumb,
+    kScrollbarHorizontalTrack,
+    kScrollbarVerticalTrack,
+    kCheckbox,
+    kRadio,
+    kPushButton,
+    kTextField,
+    kMenuList,
+    kSliderTrack,
+    kSliderThumb,
+    kInnerSpinButton,
+    kProgressBar,
+    kMaxPart,
+  };
+
+  // The state of the part.
+  enum State {
+    kDisabled,
+    kHovered,
+    kNormal,
+    kPressed,
+    kMaxState,
+  };
+
+  // Each structure below hold extra information needed when painting a given
+  // part.
+
+  struct ScrollbarTrackExtraParams {
+    int track_x;
+    int track_y;
+    int track_width;
+    int track_height;
+  };
+
+  struct ButtonExtraParams {
+    bool checked;
+    bool indeterminate;  // Whether the button state is indeterminate.
+    bool is_default;  // Whether the button is default button.
+    bool has_border;
+    int classic_state;  // Used on Windows when uxtheme is not available.
+    SkColor background_color;
+  };
+
+  struct TextFieldExtraParams {
+    bool is_text_area;
+    bool is_listbox;
+    SkColor background_color;
+  };
+
+  struct MenuListExtraParams {
+    bool has_border;
+    bool has_border_radius;
+    int arrow_x;
+    int arrow_y;
+    SkColor background_color;
+  };
+
+  struct SliderExtraParams {
+    bool vertical;
+    bool in_drag;
+  };
+
+  struct InnerSpinButtonExtraParams {
+    bool spin_up;
+    bool read_only;
+  };
+
+  struct ProgressBarExtraParams {
+    bool determinate;
+    int value_rect_x;
+    int value_rect_y;
+    int value_rect_width;
+    int value_rect_height;
+  };
+
+  union ExtraParams {
+    ScrollbarTrackExtraParams scrollbar_track;
+    ButtonExtraParams button;
+    MenuListExtraParams menu_list;
+    SliderExtraParams slider;
+    TextFieldExtraParams text_field;
+    InnerSpinButtonExtraParams inner_spin;
+    ProgressBarExtraParams progress_bar;
+  };
+
+  // Return the size of the part.
+  virtual Size GetPartSize(Part part) const = 0;
+
+  // Paint the part to the canvas.
+  virtual void Paint(skia::PlatformCanvas* canvas,
+                     Part part,
+                     State state,
+                     const gfx::Rect& rect,
+                     const ExtraParams& extra) const = 0;
+
+  // Supports theme specific colors.
+  void SetScrollbarColors(unsigned inactive_color,
+                          unsigned active_color,
+                          unsigned track_color) const;
+
+  // Returns a shared instance of the native theme.
+  // The retuned object should not be deleted by the caller.  This function
+  // is not thread safe and should only be called from the UI thread.
+  static const NativeTheme* instance();
+
+ protected:
+  NativeTheme() {}
+  virtual ~NativeTheme() {}
+
+ private:
+  static unsigned int thumb_inactive_color_;
+  static unsigned int thumb_active_color_;
+  static unsigned int track_color_;
+
+  DISALLOW_COPY_AND_ASSIGN(NativeTheme);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_NATIVE_THEME_H_