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      1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include "chrome/common/badge_util.h"
      6 
      7 #include "base/logging.h"
      8 #include "base/strings/utf_string_conversions.h"
      9 #include "grit/ui_resources.h"
     10 #include "third_party/skia/include/core/SkPaint.h"
     11 #include "third_party/skia/include/core/SkTypeface.h"
     12 #include "ui/base/resource/resource_bundle.h"
     13 #include "ui/gfx/canvas.h"
     14 #include "ui/gfx/font.h"
     15 #include "ui/gfx/rect.h"
     16 #include "ui/gfx/size.h"
     17 
     18 namespace {
     19 
     20 // Different platforms need slightly different constants to look good.
     21 #if defined(OS_WIN)
     22 const float kTextSize = 10;
     23 const int kBottomMarginBrowserAction = 0;
     24 const int kBottomMarginPageAction = 2;
     25 const int kPadding = 2;
     26 // The padding between the top of the badge and the top of the text.
     27 const int kTopTextPadding = -1;
     28 #elif defined(OS_MACOSX)
     29 const float kTextSize = 9.0;
     30 const int kBottomMarginBrowserAction = 5;
     31 const int kBottomMarginPageAction = 2;
     32 const int kPadding = 2;
     33 const int kTopTextPadding = 0;
     34 #elif defined(OS_CHROMEOS)
     35 const float kTextSize = 8.0;
     36 const int kBottomMarginBrowserAction = 0;
     37 const int kBottomMarginPageAction = 2;
     38 const int kPadding = 2;
     39 const int kTopTextPadding = 1;
     40 #elif defined(OS_POSIX)
     41 const float kTextSize = 9.0;
     42 const int kBottomMarginBrowserAction = 0;
     43 const int kBottomMarginPageAction = 2;
     44 const int kPadding = 2;
     45 const int kTopTextPadding = 0;
     46 #endif
     47 
     48 const int kBadgeHeight = 11;
     49 const int kMaxTextWidth = 23;
     50 
     51 // The minimum width for center-aligning the badge.
     52 const int kCenterAlignThreshold = 20;
     53 
     54 }  // namespace
     55 
     56 namespace badge_util {
     57 
     58 SkPaint* GetBadgeTextPaintSingleton() {
     59 #if defined(OS_MACOSX)
     60   const char kPreferredTypeface[] = "Helvetica Bold";
     61 #else
     62   const char kPreferredTypeface[] = "Arial";
     63 #endif
     64 
     65   static SkPaint* text_paint = NULL;
     66   if (!text_paint) {
     67     text_paint = new SkPaint;
     68     text_paint->setAntiAlias(true);
     69     text_paint->setTextAlign(SkPaint::kLeft_Align);
     70 
     71     skia::RefPtr<SkTypeface> typeface = skia::AdoptRef(
     72         SkTypeface::CreateFromName(kPreferredTypeface, SkTypeface::kBold));
     73     // Skia doesn't do any font fallback---if the user is missing the font then
     74     // typeface will be NULL. If we don't do manual fallback then we'll crash.
     75     if (typeface) {
     76       text_paint->setFakeBoldText(true);
     77     } else {
     78       // Fall back to the system font. We don't bold it because we aren't sure
     79       // how it will look.
     80       // For the most part this code path will only be hit on Linux systems
     81       // that don't have Arial.
     82       ResourceBundle& rb = ResourceBundle::GetSharedInstance();
     83       const gfx::Font& base_font = rb.GetFont(ResourceBundle::BaseFont);
     84       typeface = skia::AdoptRef(SkTypeface::CreateFromName(
     85           base_font.GetFontName().c_str(), SkTypeface::kNormal));
     86       DCHECK(typeface);
     87     }
     88 
     89     text_paint->setTypeface(typeface.get());
     90     // |text_paint| adds its own ref. Release the ref from CreateFontName.
     91   }
     92   return text_paint;
     93 }
     94 
     95 void PaintBadge(gfx::Canvas* canvas,
     96                 const gfx::Rect& bounds,
     97                 const std::string& text,
     98                 const SkColor& text_color_in,
     99                 const SkColor& background_color_in,
    100                 int icon_width,
    101                 extensions::ActionInfo::Type action_type) {
    102   if (text.empty())
    103     return;
    104 
    105   SkColor text_color = text_color_in;
    106   if (SkColorGetA(text_color_in) == 0x00)
    107     text_color = SK_ColorWHITE;
    108 
    109   SkColor background_color = background_color_in;
    110   if (SkColorGetA(background_color_in) == 0x00)
    111       background_color = SkColorSetARGB(255, 218, 0, 24);
    112 
    113   canvas->Save();
    114 
    115   SkPaint* text_paint = badge_util::GetBadgeTextPaintSingleton();
    116   text_paint->setTextSize(SkFloatToScalar(kTextSize));
    117   text_paint->setColor(text_color);
    118 
    119   // Calculate text width. We clamp it to a max size.
    120   SkScalar sk_text_width = text_paint->measureText(text.c_str(), text.size());
    121   int text_width = std::min(kMaxTextWidth, SkScalarFloorToInt(sk_text_width));
    122 
    123   // Calculate badge size. It is clamped to a min width just because it looks
    124   // silly if it is too skinny.
    125   int badge_width = text_width + kPadding * 2;
    126   // Force the pixel width of badge to be either odd (if the icon width is odd)
    127   // or even otherwise. If there is a mismatch you get http://crbug.com/26400.
    128   if (icon_width != 0 && (badge_width % 2 != icon_width % 2))
    129     badge_width += 1;
    130   badge_width = std::max(kBadgeHeight, badge_width);
    131 
    132   // Paint the badge background color in the right location. It is usually
    133   // right-aligned, but it can also be center-aligned if it is large.
    134   int rect_height = kBadgeHeight;
    135   int bottom_margin =
    136       action_type == extensions::ActionInfo::TYPE_BROWSER ?
    137       kBottomMarginBrowserAction : kBottomMarginPageAction;
    138   int rect_y = bounds.bottom() - bottom_margin - kBadgeHeight;
    139   int rect_width = badge_width;
    140   int rect_x = (badge_width >= kCenterAlignThreshold) ?
    141       bounds.x() + (bounds.width() - badge_width) / 2 :
    142       bounds.right() - badge_width;
    143   gfx::Rect rect(rect_x, rect_y, rect_width, rect_height);
    144 
    145   SkPaint rect_paint;
    146   rect_paint.setStyle(SkPaint::kFill_Style);
    147   rect_paint.setAntiAlias(true);
    148   rect_paint.setColor(background_color);
    149   canvas->DrawRoundRect(rect, 2, rect_paint);
    150 
    151   // Overlay the gradient. It is stretchy, so we do this in three parts.
    152   ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
    153   gfx::ImageSkia* gradient_left = rb.GetImageSkiaNamed(
    154       IDR_BROWSER_ACTION_BADGE_LEFT);
    155   gfx::ImageSkia* gradient_right = rb.GetImageSkiaNamed(
    156       IDR_BROWSER_ACTION_BADGE_RIGHT);
    157   gfx::ImageSkia* gradient_center = rb.GetImageSkiaNamed(
    158       IDR_BROWSER_ACTION_BADGE_CENTER);
    159 
    160   canvas->DrawImageInt(*gradient_left, rect.x(), rect.y());
    161   canvas->TileImageInt(*gradient_center,
    162       rect.x() + gradient_left->width(),
    163       rect.y(),
    164       rect.width() - gradient_left->width() - gradient_right->width(),
    165       rect.height());
    166   canvas->DrawImageInt(*gradient_right,
    167       rect.right() - gradient_right->width(), rect.y());
    168 
    169   // Finally, draw the text centered within the badge. We set a clip in case the
    170   // text was too large.
    171   rect.Inset(kPadding, 0);
    172   canvas->ClipRect(rect);
    173   canvas->sk_canvas()->drawText(
    174       text.c_str(), text.size(),
    175       SkFloatToScalar(rect.x() +
    176                       static_cast<float>(rect.width() - text_width) / 2),
    177       SkFloatToScalar(rect.y() + kTextSize + kTopTextPadding),
    178       *text_paint);
    179   canvas->Restore();
    180 }
    181 
    182 }  // namespace badge_util
    183