[Transparency] add javascript function and manifest, OSX Implementation, stubs for Linux/Windows

Author: jefry-vcube

src/api/window/window.cc

@@ -268,6 +268,10 @@ void Window::Call(const std::string& method,
     std::string label;
     if (arguments.GetString(0, &label))
       shell_->window()->SetBadgeLabel(label);
+  } else if (method == "SetTransparent") {
+    bool transparent;
+    if (arguments.GetBoolean(0, &transparent))
+      shell_->window()->SetTransparent(transparent);
   } else if (method == "SetProgressBar") {
     double progress;
     if (arguments.GetDouble(0, &progress))
@@ -315,6 +319,9 @@ void Window::CallSync(const std::string& method,
     gfx::Point position = shell_->window()->GetPosition();
     result->AppendInteger(position.x());
     result->AppendInteger(position.y());
+  } else if (method == "IsTransparent") {
+    bool transparent = shell_->window()->IsTransparent();
+    result->AppendBoolean(transparent);
   } else if (method == "IsDevToolsOpen") {
     result->AppendBoolean(shell_->devToolsOpen());
   } else if (method == "ShowDevTools") {

src/api/window_bindings.js

@@ -249,6 +249,11 @@ Window.prototype.__defineGetter__('isFullscreen', function() {
   var result = CallObjectMethodSync(this, 'IsFullscreen', []);
   return Boolean(result[0]);
 });
+  
+Window.prototype.__defineGetter__('isTransparent', function() {
+  var result = CallObjectMethodSync(this, 'IsTransparent', []);
+  return Boolean(result[0]);
+});
 
 Window.prototype.__defineSetter__('isKioskMode', function(flag) {
   if (flag)
@@ -425,6 +430,10 @@ Window.prototype.setProgressBar = function(progress) {
     throw new String('progress must be a number');
   CallObjectMethod(this, 'SetProgressBar', [ progress ]);
 }
+  
+Window.prototype.setTransparent = function(transparent) {
+  CallObjectMethod(this, 'SetTransparent', [ transparent ]);
+}
 
 Window.prototype.setPosition = function(position) {
   if (position != 'center' && position != 'mouse')

src/browser/native_window.cc

@@ -69,9 +69,11 @@ NativeWindow* NativeWindow::Create(const base::WeakPtr<content::Shell>& shell,
 NativeWindow::NativeWindow(const base::WeakPtr<content::Shell>& shell,
                            base::DictionaryValue* manifest)
     : shell_(shell),
+      transparent_(false),
       has_frame_(true),
       capture_page_helper_(NULL) {
   manifest->GetBoolean(switches::kmFrame, &has_frame_);
+  manifest->GetBoolean(switches::kmTransparent, &transparent_);
 
   LoadAppIconFromPackage(manifest);
 }

src/browser/native_window.h

@@ -88,6 +88,7 @@ class NativeWindow {
   virtual void Restore() = 0;
   virtual void SetFullscreen(bool fullscreen) = 0;
   virtual bool IsFullscreen() = 0;
+  virtual void SetTransparent(bool transparent) = 0;
   virtual void SetSize(const gfx::Size& size) = 0;
   virtual gfx::Size GetSize() = 0;
   virtual void SetMinimumSize(int width, int height) = 0;
@@ -140,6 +141,7 @@ class NativeWindow {
   bool has_frame() const { return has_frame_; }
   const gfx::Image& app_icon() const { return app_icon_; }
   void CapturePage(const std::string& image_format);
+  bool IsTransparent() { return transparent_; }
 
  protected:
   void OnNativeWindowDestory() {
@@ -151,6 +153,8 @@ class NativeWindow {
 
   // Weak reference to parent.
   base::WeakPtr<content::Shell> shell_;
+  
+  bool transparent_;
 
   bool has_frame_;
 

src/browser/native_window_aura.h

@@ -78,6 +78,7 @@ class NativeWindowAura : public NativeWindow,
   virtual void Restore() OVERRIDE;
   virtual void SetFullscreen(bool fullscreen) OVERRIDE;
   virtual bool IsFullscreen() OVERRIDE;
+  virtual void SetTransparent(bool transparent) OVERRIDE;
   virtual void SetSize(const gfx::Size& size) OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
   virtual void SetMinimumSize(int width, int height) OVERRIDE;

src/browser/native_window_gtk.h

@@ -48,6 +48,7 @@ class NativeWindowGtk : public NativeWindow {
   virtual void Restore() OVERRIDE;
   virtual void SetFullscreen(bool fullscreen) OVERRIDE;
   virtual bool IsFullscreen() OVERRIDE;
+  virtual void SetTransparent(bool transparent) OVERRIDE;
   virtual void SetSize(const gfx::Size& size) OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
   virtual void SetMinimumSize(int width, int height) OVERRIDE;

src/browser/native_window_mac.h

@@ -52,6 +52,7 @@ class NativeWindowCocoa : public NativeWindow {
   virtual void Restore() OVERRIDE;
   virtual void SetFullscreen(bool fullscreen) OVERRIDE;
   virtual bool IsFullscreen() OVERRIDE;
+  virtual void SetTransparent(bool transparent) OVERRIDE;
   virtual void SetSize(const gfx::Size& size) OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
   virtual void SetMinimumSize(int width, int height) OVERRIDE;
@@ -111,6 +112,9 @@ class NativeWindowCocoa : public NativeWindow {
 
   // Delegate to the toolbar.
   base::scoped_nsobject<ShellToolbarDelegate> toolbar_delegate_;
+  
+  // Data for transparency
+  NSColor *opaque_color_;
 
   bool is_fullscreen_;
   bool is_kiosk_;

src/browser/native_window_mac.mm

@@ -35,7 +35,7 @@
 #include "content/nw/src/nw_package.h"
 #include "content/nw/src/nw_shell.h"
 #include "content/public/browser/native_web_keyboard_event.h"
-#include "content/public/browser/render_widget_host_view.h"
+#include "content/browser/renderer_host/render_widget_host_view_mac.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/common/draggable_region.h"
 #include "third_party/skia/include/core/SkRegion.h"
@@ -282,7 +282,11 @@ - (void)drawCustomFrameRect:(NSRect)rect forView:(NSView*)view {
   [[NSBezierPath bezierPathWithRoundedRect:[view bounds]
                                    xRadius:cornerRadius
                                    yRadius:cornerRadius] addClip];
-  [[NSColor whiteColor] set];
+  if ([self isOpaque])
+    [[NSColor whiteColor] set];
+  else
+    [[NSColor clearColor] set];
+
   NSRectFill(rect);
 }
 
@@ -385,10 +389,13 @@ - (void)drawRect:(NSRect)dirtyRect {
                       defer:NO];
   }
   window_ = shell_window;
+  opaque_color_ = [window() backgroundColor];
   [shell_window setShell:shell];
   [[window() contentView] setWantsLayer:YES];
   [window() setDelegate:[[NativeWindowDelegate alloc] initWithShell:shell]];
 
+  SetTransparent(transparent_);
+
   // Disable fullscreen button when 'fullscreen' is specified to false.
   bool fullscreen;
   if (!(manifest->GetBoolean(switches::kmFullscreen, &fullscreen) &&
@@ -539,6 +546,26 @@ - (void)drawRect:(NSRect)dirtyRect {
   return is_fullscreen_;
 }
 
+void NativeWindowCocoa::SetTransparent(bool transparent) {
+  
+  if (!transparent_ && transparent) {
+    opaque_color_ = [window() backgroundColor];
+  }
+  
+  [window() setHasShadow:transparent ? NO : YES];
+  [window() setOpaque:transparent ? NO : YES];
+  [window() setBackgroundColor:transparent ? [NSColor clearColor] : opaque_color_];
+
+  content::RenderWidgetHostViewMac* rwhv = static_cast<content::RenderWidgetHostViewMac*>(shell_->web_contents()->GetRenderWidgetHostView());
+
+  if (rwhv) {
+    rwhv->SetBackgroundOpaque(!transparent);
+    [rwhv->background_layer_ setBackgroundColor:CGColorGetConstantColor(transparent ? kCGColorClear : kCGColorWhite)];
+  }
+  
+  transparent_ = transparent;
+  
+}
 void NativeWindowCocoa::SetNonLionFullscreen(bool fullscreen) {
   if (fullscreen == is_fullscreen_)
     return;

src/common/shell_switches.cc

@@ -72,6 +72,7 @@ const char kmResizable[]  = "resizable";
 const char kmAsDesktop[]  = "as_desktop";
 const char kmFullscreen[] = "fullscreen";
 const char kmInitialFocus[] = "focus";
+const char kmTransparent[] = "transparent";
 
 // Make windows icon hide show or hide in taskbar.
 const char kmShowInTaskbar[] = "show_in_taskbar";

src/common/shell_switches.h

@@ -54,6 +54,7 @@ extern const char kmShowInTaskbar[];
 extern const char kmKiosk[];
 extern const char kmAlwaysOnTop[];
 extern const char kmInitialFocus[];
+extern const char kmTransparent[];
 
 extern const char kmWebgl[];
 extern const char kmJava[];