Make views::Label and views::Link auto-color themselves to be readable over their background colo...

views/controls/label.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 "views/controls/label.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <vector>
 
 #include "base/i18n/rtl.h"
 #include "base/logging.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/text/text_elider.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/font.h"
 #include "ui/gfx/insets.h"
 #include "views/background.h"
 
-namespace views {
+namespace {
 
 // The colors to use for enabled and disabled labels.
-static SkColor kEnabledColor;
-static SkColor kDisabledColor;
+SkColor kDefaultEnabledColor;

[sky, 2011/10/11 00:42:35]

Having these away from where you initialize them makes it easy to try and use
one and not realize it wasn't initialized. It looks like you only use them in
Init, could they be static there?

[Peter Kasting, 2011/10/11 01:05:47]

Sure.  Moved.  (Also for link.cc.)

+SkColor kDefaultDisabledColor;
+SkColor kDefaultBackgroundColor;
+
+};

[sky, 2011/10/11 00:42:35]

nit: no ;

+
+namespace views {
 
 // static
 const char Label::kViewClassName[] = "views/Label";
 
 const int Label::kFocusBorderPadding = 1;
 
 Label::Label() {
   Init(string16(), GetDefaultFont());
 }
 
@@ skipping 33 matching lines @@
   url_set_ = true;
   text_size_valid_ = false;
   PreferredSizeChanged();
   SchedulePaint();
 }
 
 const GURL Label::GetURL() const {
   return url_set_ ? url_ : GURL(UTF16ToUTF8(text_));
 }
 
-void Label::SetColor(const SkColor& color) {
-  color_ = color;
+void Label::SetEnabledColor(const SkColor& color) {
+  requested_enabled_color_ = color;
+  RecalculateColors();
 }
 
-SkColor Label::GetColor() const {
-  return color_;
+void Label::SetDisabledColor(const SkColor& color) {
+  requested_disabled_color_ = color;
+  RecalculateColors();
 }
 
-void Label::MakeReadableOverBackgroundColor(const SkColor& background_color) {
-  SetColor(color_utils::GetReadableColor(
-      IsEnabled() ? kEnabledColor : kDisabledColor, background_color));
+void Label::SetBackgroundColor(const SkColor& color) {
+  background_color_ = color;
+  RecalculateColors();
 }
 
 void Label::SetHorizontalAlignment(Alignment alignment) {
   // If the View's UI layout is right-to-left and rtl_alignment_mode_ is
   // USE_UI_ALIGNMENT, we need to flip the alignment so that the alignment
   // settings take into account the text directionality.
   if (base::i18n::IsRTL() && (rtl_alignment_mode_ == USE_UI_ALIGNMENT) &&
       (alignment != ALIGN_CENTER))
     alignment = (alignment == ALIGN_LEFT) ? ALIGN_RIGHT : ALIGN_LEFT;
   if (horiz_alignment_ != alignment) {
@@ skipping 104 matching lines @@
   if (!is_multi_line_)
     return View::GetHeightForWidth(w);
 
   w = std::max(0, w - GetInsets().width());
   int h = font_.GetHeight();
   gfx::CanvasSkia::SizeStringInt(text_, font_, &w, &h,
                                  ComputeMultiLineFlags());
   return h + GetInsets().height();
 }
 
-void Label::OnEnabledChanged() {
-  View::OnEnabledChanged();
-  SetColor(IsEnabled() ? kEnabledColor : kDisabledColor);
-}
-
 std::string Label::GetClassName() const {
   return kViewClassName;
 }
 
 bool Label::HitTest(const gfx::Point& l) const {
   return false;
 }
 
 void Label::OnMouseMoved(const MouseEvent& event) {
   UpdateContainsMouse(event);
@@ skipping 28 matching lines @@
 void Label::GetAccessibleState(ui::AccessibleViewState* state) {
   state->role = ui::AccessibilityTypes::ROLE_STATICTEXT;
   state->state = ui::AccessibilityTypes::STATE_READONLY;
   state->name = text_;
 }
 
 void Label::PaintText(gfx::Canvas* canvas,
                       const string16& text,
                       const gfx::Rect& text_bounds,
                       int flags) {
-  canvas->DrawStringInt(text, font_, color_,
-                        text_bounds.x(), text_bounds.y(),
-                        text_bounds.width(), text_bounds.height(), flags);
+  canvas->DrawStringInt(text, font_,
+      IsEnabled() ? actual_enabled_color_ : actual_disabled_color_,
+      text_bounds.x(), text_bounds.y(), text_bounds.width(),
+      text_bounds.height(), flags);
 
   if (HasFocus() || paint_as_focused_) {
     gfx::Rect focus_bounds = text_bounds;
     focus_bounds.Inset(-kFocusBorderPadding, -kFocusBorderPadding);
     canvas->DrawFocusRect(focus_bounds.x(), focus_bounds.y(),
                           focus_bounds.width(), focus_bounds.height());
   }
 }
 
 gfx::Size Label::GetTextSize() const {
@@ skipping 42 matching lines @@
 
 // static
 gfx::Font Label::GetDefaultFont() {
   return ResourceBundle::GetSharedInstance().GetFont(ResourceBundle::BaseFont);
 }
 
 void Label::Init(const string16& text, const gfx::Font& font) {
   static bool initialized = false;
   if (!initialized) {
 #if defined(OS_WIN)
-    kEnabledColor = color_utils::GetSysSkColor(COLOR_WINDOWTEXT);
-    kDisabledColor = color_utils::GetSysSkColor(COLOR_GRAYTEXT);
+    kDefaultEnabledColor = color_utils::GetSysSkColor(COLOR_WINDOWTEXT);
+    kDefaultDisabledColor = color_utils::GetSysSkColor(COLOR_GRAYTEXT);
+    kDefaultBackgroundColor = color_utils::GetSysSkColor(COLOR_WINDOW);
 #else
     // TODO(beng): source from theme provider.
-    kEnabledColor = SK_ColorBLACK;
-    kDisabledColor = SK_ColorGRAY;
+    kDefaultEnabledColor = SK_ColorBLACK;
+    kDefaultDisabledColor = SK_ColorGRAY;
+    kDefaultBackgroundColor = SK_ColorWHITE;
 #endif
 
     initialized = true;
   }
 
   contains_mouse_ = false;
   font_ = font;
   text_size_valid_ = false;
-  SetText(text);
   url_set_ = false;
-  color_ = kEnabledColor;
+  requested_enabled_color_ = kDefaultEnabledColor;
+  requested_disabled_color_ = kDefaultDisabledColor;
+  background_color_ = kDefaultBackgroundColor;
+  auto_color_readability_ = true;
+  RecalculateColors();
   horiz_alignment_ = ALIGN_CENTER;
   is_multi_line_ = false;
   allow_character_break_ = false;
   elide_in_middle_ = false;
   collapse_when_hidden_ = false;
   rtl_alignment_mode_ = USE_UI_ALIGNMENT;
   paint_as_focused_ = false;
   has_focus_border_ = false;
+
+  SetText(text);
+}
+
+void Label::RecalculateColors() {
+  actual_enabled_color_ = auto_color_readability_ ?
+      color_utils::GetReadableColor(requested_enabled_color_,
+                                    background_color_) :
+      requested_enabled_color_;
+  actual_disabled_color_ = auto_color_readability_ ?
+      color_utils::GetReadableColor(requested_disabled_color_,
+                                    background_color_) :
+      requested_disabled_color_;
 }
 
 void Label::UpdateContainsMouse(const MouseEvent& event) {
   SetContainsMouse(GetTextBounds().Contains(event.x(), event.y()));
 }
 
 void Label::SetContainsMouse(bool contains_mouse) {
   if (contains_mouse_ == contains_mouse)
     return;
   contains_mouse_ = contains_mouse;
@@ skipping 103 matching lines @@
   // it is right aligned. Otherwise, its directionality is forced to be LTR.
   if (rtl_alignment_mode_ == AUTO_DETECT_ALIGNMENT) {
     if (horiz_alignment_ == ALIGN_RIGHT)
       *flags |= gfx::Canvas::FORCE_RTL_DIRECTIONALITY;
     else
       *flags |= gfx::Canvas::FORCE_LTR_DIRECTIONALITY;
   }
 }
 
 }  // namespace views