extensions/browser/extension_icon_placeholder.cc

   1 // Copyright 2015 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 "extensions/browser/extension_icon_placeholder.h"
   6
   7 #include "base/strings/string_util.h"
   8 #include "base/strings/utf_string_conversions.h"
   9 #include "extensions/grit/extensions_browser_resources.h"
  10 #include "ui/base/resource/resource_bundle.h"
  11 #include "ui/gfx/canvas.h"
  12 #include "ui/gfx/codec/png_codec.h"
  13 #include "ui/gfx/geometry/rect.h"
  14 #include "ui/gfx/geometry/size.h"
  15 #include "ui/gfx/image/canvas_image_source.h"
  16 #include "ui/gfx/image/image_skia.h"
  17
  18 namespace extensions {
  19
  20 namespace {
  21
  22 // Returns the FontStyle to use for the given icon |size|.
  23 ui::ResourceBundle::FontStyle GetFontStyleForIconSize(
  24     extension_misc::ExtensionIcons size) {
  25   switch (size) {
  26     case extension_misc::EXTENSION_ICON_INVALID:
  27     case extension_misc::EXTENSION_ICON_BITTY:
  28       return ui::ResourceBundle::SmallFont;
  29     case extension_misc::EXTENSION_ICON_ACTION:
  30     case extension_misc::EXTENSION_ICON_SMALLISH:
  31     case extension_misc::EXTENSION_ICON_SMALL:
  32       return ui::ResourceBundle::MediumFont;
  33     case extension_misc::EXTENSION_ICON_MEDIUM:
  34     case extension_misc::EXTENSION_ICON_LARGE:
  35     case extension_misc::EXTENSION_ICON_EXTRA_LARGE:
  36     case extension_misc::EXTENSION_ICON_GIGANTOR:
  37       return ui::ResourceBundle::LargeFont;
  38   }
  39   NOTREACHED();
  40   return ui::ResourceBundle::MediumFont;
  41 }
  42
  43 // Returns the background image to use for the given icon |size|.
  44 gfx::Image GetBackgroundImageForIconSize(extension_misc::ExtensionIcons size) {
  45   int resource_id = 0;
  46   // Right now, we have resources for a 19x19 (action) and a 48x48 (extensions
  47   // page icon). The implementation of the placeholder scales these correctly,
  48   // so it's not a big deal to use these for other sizes, but if it's something
  49   // that will be done frequently, we should probably make a devoted asset for
  50   // that size.
  51   switch (size) {
  52     case extension_misc::EXTENSION_ICON_INVALID:
  53     case extension_misc::EXTENSION_ICON_BITTY:
  54     case extension_misc::EXTENSION_ICON_ACTION:
  55     case extension_misc::EXTENSION_ICON_SMALLISH:
  56     case extension_misc::EXTENSION_ICON_SMALL:
  57       resource_id = IDR_EXTENSION_ACTION_PLAIN_BACKGROUND;
  58       break;
  59     case extension_misc::EXTENSION_ICON_MEDIUM:
  60     case extension_misc::EXTENSION_ICON_LARGE:
  61     case extension_misc::EXTENSION_ICON_EXTRA_LARGE:
  62     case extension_misc::EXTENSION_ICON_GIGANTOR:
  63       resource_id = IDR_EXTENSION_ICON_PLAIN_BACKGROUND;
  64       break;
  65   }
  66   return ui::ResourceBundle::GetSharedInstance().GetImageNamed(resource_id);
  67 }
  68
  69 }  // namespace
  70
  71 ExtensionIconPlaceholder::ExtensionIconPlaceholder(
  72     extension_misc::ExtensionIcons size,
  73     const std::string& letter)
  74     : gfx::CanvasImageSource(gfx::Size(size, size), false),
  75       icon_size_(size),
  76       letter_(base::UTF8ToUTF16(letter.substr(0, 1))),
  77       base_image_(GetBackgroundImageForIconSize(size)) {
  78 }
  79
  80 ExtensionIconPlaceholder::~ExtensionIconPlaceholder() {
  81 }
  82
  83 gfx::Image ExtensionIconPlaceholder::CreateImage(
  84     extension_misc::ExtensionIcons size,
  85     const std::string& name) {
  86   return gfx::Image(gfx::ImageSkia(new ExtensionIconPlaceholder(size, name),
  87                                    gfx::Size(size, size)));
  88 }
  89
  90 void ExtensionIconPlaceholder::Draw(gfx::Canvas* canvas) {
  91   // Draw the background image, correctly scaled.
  92   canvas->DrawImageInt(*base_image_.ToImageSkia(), 0, 0,
  93                        base_image_.Size().width(), base_image_.Size().height(),
  94                        0, 0, size().width(), size().height(), true);
  95   gfx::Rect bounds(size().width(), size().height());
  96   // Draw the letter on top.
  97   canvas->DrawStringRectWithFlags(
  98       letter_, ui::ResourceBundle::GetSharedInstance().GetFontList(
  99                    GetFontStyleForIconSize(icon_size_)),
 100       SK_ColorWHITE, bounds, gfx::Canvas::TEXT_ALIGN_CENTER);
 101 }
 102
 103 }  // namespace extensions