Drop shadows for packaged apps on the OSX App Launcher.

ui/app_list/cocoa/apps_grid_view_item.mm

Index: ui/app_list/cocoa/apps_grid_view_item.mm
diff --git a/ui/app_list/cocoa/apps_grid_view_item.mm b/ui/app_list/cocoa/apps_grid_view_item.mm
index e09065257b1f1e7df94c847077757df45f404750..44484875a4b703391117aef7f4faf2afbed94b0f 100644
--- a/ui/app_list/cocoa/apps_grid_view_item.mm
+++ b/ui/app_list/cocoa/apps_grid_view_item.mm
@@ -14,6 +14,7 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/image/image_skia_util_mac.h"
 #include "ui/gfx/font.h"
+#include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"
 
 namespace {
 
@@ -90,6 +91,18 @@ void ItemModelObserverBridge::ItemPercentDownloadedChanged() {
 
 @end
 
+@interface AppsGridItemButtonCell : NSButtonCell {
+ @private
+  BOOL hasShadow_;
+}
+
+@property(assign, nonatomic) BOOL hasShadow;
+
+@end
+
+@interface AppsGridItemButton : NSButton;
+@end
+
 @implementation AppsGridItemBackgroundView
 
 - (NSButton*)button {
@@ -149,8 +162,8 @@ void ItemModelObserverBridge::ItemPercentDownloadedChanged() {
 
 - (id)initWithSize:(NSSize)tileSize {
   if ((self = [super init])) {
-    scoped_nsobject<NSButton> prototypeButton(
-        [[NSButton alloc] initWithFrame:NSMakeRect(
+    scoped_nsobject<AppsGridItemButton> prototypeButton(
+        [[AppsGridItemButton alloc] initWithFrame:NSMakeRect(
             0, 0, tileSize.width, tileSize.height - kTileTopPadding)]);
 
     // This NSButton style always positions the icon at the very top of the
@@ -182,6 +195,7 @@ void ItemModelObserverBridge::ItemPercentDownloadedChanged() {
   NSButton* button = [self button];
   [button setTitle:base::SysUTF8ToNSString(itemModel->title())];
   [button setImage:gfx::NSImageFromImageSkia(itemModel->icon())];
+  [[button cell] setHasShadow:itemModel->has_shadow()];
   observerBridge_.reset(new app_list::ItemModelObserverBridge(self, itemModel));
 
   if (trackingArea_.get())
@@ -225,3 +239,39 @@ void ItemModelObserverBridge::ItemPercentDownloadedChanged() {
 }
 
 @end
+
+@implementation AppsGridItemButton
+
++ (Class)cellClass {
+  return [AppsGridItemButtonCell class];
+}
+
+@end
+
+@implementation AppsGridItemButtonCell
+
+@synthesize hasShadow = hasShadow_;
+
+- (void)drawImage:(NSImage*)image
+        withFrame:(NSRect)frame
+           inView:(NSView*)controlView {
+  if (!hasShadow_) {
+    [super drawImage:image
+           withFrame:frame
+              inView:controlView];
+    return;
+  }
+
+  scoped_nsobject<NSShadow> shadow([[NSShadow alloc] init]);
+  gfx::ScopedNSGraphicsContextSaveGState context;
+  [shadow setShadowOffset:NSMakeSize(0, -2)];
+  [shadow setShadowBlurRadius:2.0];
+  [shadow setShadowColor:[[NSColor blackColor] colorWithAlphaComponent:0.14]];

[tapted, 2013/05/17 14:50:39]

note: source for these numbers
https://code.google.com/p/chromium/codesearch#chromium/src/ui/app_list/views/...

  const gfx::ShadowValue kIconShadows[] = {
    gfx::ShadowValue(gfx::Point(0, 2), 2, SkColorSetARGB(0x24, 0, 0, 0)),
  };
  icon_shadows_.assign(kIconShadows, kIconShadows + arraysize(kIconShadows));

[sail, 2013/05/17 17:41:33]

A more direct way to do this is [NSColor colorWithCalibratedWhite:0 alpha:0.14]

[tapted, 2013/05/17 23:39:30]

Done.

+  [shadow set];
+
+  [super drawImage:image
+         withFrame:frame
+            inView:controlView];
+}
+
+@end