Support detaching/attaching panels via inter-strip drags.

chrome/browser/ui/panels/panel_window_controller_cocoa.mm

 // Copyright (c) 2012 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/ui/panels/panel_window_controller_cocoa.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/logging.h"
 #include "base/mac/bundle_locations.h"
@@ skipping 40 matching lines @@
 // Replicate specific 10.6 SDK declarations for building with prior SDKs.
 #if !defined(MAC_OS_X_VERSION_10_6) || \
     MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_6
 
 enum {
   NSWindowCollectionBehaviorParticipatesInCycle = 1 << 5
 };
 
 #endif  // MAC_OS_X_VERSION_10_6
 
+namespace {
+
+// Converts a point from the Cocoa screen coordinates (with (0,0) in the
+// low-left corner of the primary screen) to the platfrom-independent screen
+// coordinates (with the (0,0) in the top-left corner).
+gfx::Point ConvertPointFromCocoaCoordinates(NSPoint point) {
+  // Flip coordinates based on the primary screen.
+  NSScreen* screen = [[NSScreen screens] objectAtIndex:0];
+
+  return gfx::Point(point.x, NSHeight([screen frame]) - point.y);
+}
+
+}  // namespace
+
 @implementation PanelWindowCocoaImpl
 - (NSRect)constrainFrameRect:(NSRect)frameRect toScreen:(NSScreen *)screen {
   return frameRect;
 }
 
 - (BOOL)canBecomeKeyWindow {
   PanelWindowControllerCocoa* controller =
       static_cast<PanelWindowControllerCocoa*>([self delegate]);
   return [controller canBecomeKeyWindow];
 }
@@ skipping 324 matching lines @@
 
   [NSMenu popUpContextMenu:[settingsMenuController menu]
                  withEvent:[NSApp currentEvent]
                    forView:button];
 }
 
 - (BOOL)isDraggable {
   return windowShim_->panel()->draggable();
 }
 
-- (void)startDrag {
+- (void)startDrag:(NSPoint)mouseLocation {
   animateOnBoundsChange_ = NO;
-  windowShim_->panel()->manager()->StartDragging(windowShim_->panel());
+  windowShim_->panel()->manager()->StartDragging(
+      windowShim_->panel(), ConvertPointFromCocoaCoordinates(mouseLocation));
 }
 
 - (void)endDrag:(BOOL)cancelled {
   animateOnBoundsChange_ = YES;
   windowShim_->panel()->manager()->EndDragging(cancelled);
 }
 
-- (void)dragWithDeltaX:(int)deltaX
-                deltaY:(int)deltaY {
-  windowShim_->panel()->manager()->Drag(deltaX, deltaY);
+- (void)drag:(NSPoint)mouseLocation {
+  windowShim_->panel()->manager()->Drag(
+      ConvertPointFromCocoaCoordinates(mouseLocation));
 }
 
 - (void)setPanelFrame:(NSRect)frame
               animate:(BOOL)animate {
   // Setup the whole window as the tracking area so that we can get notified
   // when the mouse enters or leaves the window. This will make us be able to
   // show or hide settings button accordingly.
   NSRect localBounds = frame;
   localBounds.origin = NSZeroPoint;
   windowTrackingArea_.reset(
@@ skipping 189 matching lines @@
 }
 
 - (BOOL)canBecomeKeyWindow {
   // Panel can only gain focus if it is expanded. Minimized panels do not
   // participate in Cmd-~ rotation.
   // TODO(dimich): If it will be ever desired to expand/focus the Panel on
   // keyboard navigation or via main menu, the care should be taken to avoid
   // cases when minimized Panel is getting keyboard input, invisibly.
   return windowShim_->panel()->expansion_state() == Panel::EXPANDED;
 }
+
+- (void)setAlwaysOnTop:(bool)onTop {
+  NSWindow* window = [self window];
+  [window setLevel:(onTop ? NSStatusWindowLevel : NSNormalWindowLevel)];
+}
 @end