MacViews: Use Cocoa folder icons in tree views.

chrome/browser/resource_delegate_mac.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 UI_BASE_RESOURCE_RESOURCE_DELEGATE_MAC_H_

[tapted, 2016/01/14 23:43:50]

include guard isn't right

[karandeepb, 2016/01/18 00:31:17]

Done.

+#define UI_BASE_RESOURCE_RESOURCE_DELEGATE_MAC_H_
+
+#include <map>
+
+#include "base/macros.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/gfx/image/image.h"
+
+#if defined(__OBJC__)
+@class NSString;
+#else
+class NSString;
+#endif
+
+namespace ui {
+
+// A singleton resource bundle delegate. Primary purpose is to intercept certain
+// resource ids and to provide Mac specific assets for them at runtime.
+class UI_BASE_EXPORT MacResourceDelegate : public ui::ResourceBundle::Delegate {
+ public:
+  MacResourceDelegate();
+  ~MacResourceDelegate() override;
+
+  // ui:ResourceBundle::Delegate implementation:
+  base::FilePath GetPathForResourcePack(const base::FilePath& pack_path,
+                                        ui::ScaleFactor scale_factor) override;
+  base::FilePath GetPathForLocalePack(const base::FilePath& pack_path,
+                                      const std::string& locale) override;
+  gfx::Image GetImageNamed(int resource_id) override;
+  gfx::Image GetNativeImageNamed(int resource_id,
+                                 ui::ResourceBundle::ImageRTL rtl) override;
+  base::RefCountedStaticMemory* LoadDataResourceBytes(
+      int resource_id,
+      ui::ScaleFactor scale_factor) override;
+  bool GetRawDataResource(int resource_id,
+                          ui::ScaleFactor scale_factor,
+                          base::StringPiece* value) override;
+  bool GetLocalizedString(int message_id, base::string16* value) override;
+  scoped_ptr<gfx::Font> GetFont(ui::ResourceBundle::FontStyle style) override;
+
+ private:
+  enum IconSize {
+    SMALL,  // 16X16.
+    BIG     // 32X32.
+  };
+
+  class InterceptedIcon {

[tapted, 2016/01/14 23:43:50]

Skia does some crazy stuff around image loading. Typically an image is only
fully loaded (automatically) when it is first drawn to screen, since that
determines whether it needs to load a hi-dpi asset or a regular asset. This
includes fetching the appropriate representation from a wrapped NSImage if
that's required.

So, I don't think this is needed.

[karandeepb, 2016/01/18 00:31:17]

Done.

+   public:
+    explicit InterceptedIcon(NSString* file_type,
+                             bool flip_icon,
+                             IconSize icon_size);
+    ~InterceptedIcon();
+    // Returns the image for this icon. The image is loaded lazily. An empty
+    // image is returned in case the image can't be loaded.
+    const gfx::Image GetImage() const;
+
+   private:
+    // File type to which this icon corresponds.
+    NSString* file_type_;
+    // Image for this icon type.
+    mutable gfx::Image icon_image_;
+    // If true, the icon image is flipped. Used to create images for RTL
+    // contexts.
+    bool flip_icon_;
+    // The desired icon size.
+    IconSize icon_size_;
+    // True if the image has been loaded. For lazy loading of images.
+    mutable bool is_image_loaded_;
+  };
+
+  typedef std::map<int, InterceptedIcon> InterceptedIconsMap;
+
+  // A map from intercepted resource_ids to corresponding InterceptedIcon
+  // resource.
+  InterceptedIconsMap intercepted_icons_map_;

[tapted, 2016/01/14 23:43:50]

I don't think you need this

[karandeepb, 2016/01/18 00:31:17]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(MacResourceDelegate);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_RESOURCE_RESOURCE_DELEGATE_MAC_H_