MacViews: Use Cocoa folder icons in tree views.

chrome/browser/resource_delegate_mac.mm

+// 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.
+
+#include "chrome/browser/resource_delegate_mac.h"
+
+#import <Cocoa/Cocoa.h>
+
+#include "ui/resources/grit/ui_resources.h"
+#include "ui/views/resources/grit/views_resources.h"
+
+namespace ui {
+
+namespace {
+
+enum IconSize {
+  SMALL,  // 16X16.
+  BIG     // 32X32.

[tapted, 2016/01/18 04:15:42]

`BIG` is unused. I think we want

const int kFolderIconReportedSizeDIP = 16;

But only if 16 is correct. E.g. the raster asset is 19x18 pixels. Ideally, the
size on Mac would "match", but we want ensure there is no distortion. Can you
post some screenshots on the bug?

[karandeepb, 2016/01/18 09:25:40]

Done. Have attached screenshots on the bug report.

+};
+
+// Returns the icon for the given hfs_type defined in Cocoa's IconsCore.h, as a
+// gfx::Image. In case the icon can't be retreived, an empty image is returned.

[tapted, 2016/01/18 04:15:42]

I don't think the "In case the icon..." part is right. Perhaps remove that part
of the comment and DCHECK(icon); after retrieving it from NSWorkspace, since it
should "always" exist.

[karandeepb, 2016/01/18 09:25:40]

Done.

+gfx::Image ImageForHFSType(int hfs_type, IconSize icon_size) {

[tapted, 2016/01/18 04:15:42]

IconSize -> int

[karandeepb, 2016/01/18 09:25:40]

Done.

+  NSImage* icon = [[[NSWorkspace sharedWorkspace]
+      iconForFileType:NSFileTypeForHFSTypeCode(hfs_type)] retain];

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

Can you check if calling retain here is ok? gfx::Image(NSImage *) expects to
take ownership of the NSImage but it doesn't call retain on it.

[tapted, 2016/01/18 04:15:42]

ooh - yeah gfx::Image is weird. the return from iconForFileType will be
autoreleased, so it's weird to retain it here. I think we can instead do `return
gfx::Image([icon retain]);` to keep the weirdness together

[karandeepb, 2016/01/18 09:25:40]

Done.

+  NSSize desired_size;
+  switch (icon_size) {
+    case IconSize::SMALL:
+      desired_size = NSMakeSize(16, 16);
+      break;
+    case IconSize::BIG:
+      desired_size = NSMakeSize(32, 32);
+      break;
+  }
+  [icon setSize:desired_size];
+  return gfx::Image(icon);
+}
+
+}  // namespace
+
+MacResourceDelegate::MacResourceDelegate() {}
+
+MacResourceDelegate::~MacResourceDelegate() {}
+
+base::FilePath MacResourceDelegate::GetPathForResourcePack(
+    const base::FilePath& pack_path,
+    ui::ScaleFactor scale_factor) {
+  return pack_path;
+};
+
+base::FilePath MacResourceDelegate::GetPathForLocalePack(
+    const base::FilePath& pack_path,
+    const std::string& locale) {
+  return pack_path;
+};
+
+gfx::Image MacResourceDelegate::GetImageNamed(int resource_id) {
+  return GetNativeImageNamed(resource_id, ui::ResourceBundle::RTL_DISABLED);
+};
+
+gfx::Image MacResourceDelegate::GetNativeImageNamed(
+    int resource_id,
+    ui::ResourceBundle::ImageRTL rtl) {
+  // Flipped images are not used on Mac.

[tapted, 2016/01/18 04:15:42]

I think it was only used for GTK and we can remove it --
https://codereview.chromium.org/1601583002/

[karandeepb, 2016/01/18 09:25:40]

Will remove once the CL lands.

+  DCHECK_EQ(rtl, ui::ResourceBundle::RTL_DISABLED);
+
+  switch (resource_id) {

[tapted, 2016/01/18 04:15:42]

Needs a comment about why this is correct re: the _RTL assets. E.g. "On Mac,
return the same assets for the _RTL resources. Consistent with, e.g., Safari."

[karandeepb, 2016/01/18 09:25:40]

Done.

+    case IDR_FOLDER_OPEN:
+    case IDR_FOLDER_OPEN_RTL:
+      return ImageForHFSType(kOpenFolderIcon, IconSize::SMALL);
+      break;

[tapted, 2016/01/18 04:15:42]

nit: no break required

[karandeepb, 2016/01/18 09:25:40]

Done.

+    case IDR_FOLDER_CLOSED:
+    case IDR_FOLDER_CLOSED_RTL:
+      return ImageForHFSType(kGenericFolderIcon, IconSize::SMALL);
+      break;

[tapted, 2016/01/18 04:15:42]

nit: no break

[karandeepb, 2016/01/18 09:25:40]

Done.

+  }
+  return gfx::Image();
+};
+
+base::RefCountedStaticMemory* MacResourceDelegate::LoadDataResourceBytes(
+    int resource_id,
+    ui::ScaleFactor scale_factor) {
+  return nullptr;
+};
+
+bool MacResourceDelegate::GetRawDataResource(int resource_id,
+                                             ui::ScaleFactor scale_factor,
+                                             base::StringPiece* value) {
+  return false;
+};
+
+bool MacResourceDelegate::GetLocalizedString(int message_id,
+                                             base::string16* value) {
+  return false;
+};
+
+scoped_ptr<gfx::Font> MacResourceDelegate::GetFont(
+    ui::ResourceBundle::FontStyle style) {
+  return scoped_ptr<gfx::Font>();
+};
+
+}  // namespace ui