Support detaching/attaching panels via inter-strip drags.

chrome/browser/ui/panels/panel_titlebar_view_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.
 
 #import "chrome/browser/ui/panels/panel_titlebar_view_cocoa.h"
 
 #include <Carbon/Carbon.h>  // kVK_Escape
 #import <Cocoa/Cocoa.h>
 
 #include "base/logging.h"
@@ skipping 374 matching lines @@
 }
 
 - (void)didChangeMainWindow:(NSNotification*)notification {
   [self setNeedsDisplay:YES];
   [self checkMouseAndUpdateSettingsButtonVisibility];
 }
 
 - (void)mouseDown:(NSEvent*)event {
   if ([controller_ isDraggable]) {
     dragState_ = PANEL_DRAG_CAN_START;
-    dragStartLocation_ = [event locationInWindow];
+    dragStartLocation_ = [NSEvent mouseLocation];
   }
 }
 
 - (void)mouseUp:(NSEvent*)event {
   DCHECK(dragState_ != PANEL_DRAG_IN_PROGRESS);
 
   if ([event clickCount] == 1)
     [controller_ onTitlebarMouseClicked];
 }
 
 - (BOOL)exceedsDragThreshold:(NSPoint)mouseLocation {
   float deltaX = dragStartLocation_.x - mouseLocation.x;
   float deltaY = dragStartLocation_.y - mouseLocation.y;
-  return deltaX > kDragThreshold || deltaY > kDragThreshold;
+  return fabs(deltaX) > kDragThreshold || fabs(deltaY) > kDragThreshold;
 }
 
 - (void)mouseDragged:(NSEvent*)event {
   if (dragState_ == PANEL_DRAG_SUPPRESSED)
     return;
 
   // In addition to events needed to control the drag operation, fetch the right
   // mouse click events and key down events and ignore them, to prevent their
   // accumulation in the queue and "playing out" when the mouse is released.
   const NSUInteger mask =
       NSLeftMouseUpMask | NSLeftMouseDraggedMask | NSKeyUpMask |
       NSRightMouseDownMask | NSKeyDownMask ;
   BOOL keepGoing = YES;
 
   while (keepGoing) {
     base::mac::ScopedNSAutoreleasePool autorelease_pool;
 
     NSEvent* event = [NSApp nextEventMatchingMask:mask
                                         untilDate:[NSDate distantFuture]
                                            inMode:NSDefaultRunLoopMode
                                           dequeue:YES];
 
     switch ([event type]) {
       case NSLeftMouseDragged:
         if (dragState_ == PANEL_DRAG_CAN_START) {
-          if (![self exceedsDragThreshold:[event locationInWindow]])
+          if (![self exceedsDragThreshold:[NSEvent mouseLocation]])
             return;  // Don't start real drag yet.
-          [self startDrag];
+          [self startDrag:dragStartLocation_];
         }
-        [self dragWithDeltaX:[event deltaX]
-                      deltaY:[event deltaY]];
+        if (dragState_ == PANEL_DRAG_IN_PROGRESS)
+          [self drag:[NSEvent mouseLocation]];
         break;
 
       case NSKeyUp:
         if ([event keyCode] == kVK_Escape) {
           [self endDrag:YES];
           keepGoing = NO;
         }
         break;
 
       case NSLeftMouseUp:
@@ skipping 10 matching lines @@
       default:
         // Dequeue and ignore other mouse and key events so the Chrome context
         // menu does not come after right click on a page during Panel
         // rearrangement, or the keystrokes are not 'accumulated' and entered
         // at once when the drag ends.
         break;
     }
   }
 }
 
-- (void)startDrag {
+- (void)startDrag:(NSPoint)mouseLocation {
   DCHECK(dragState_ == PANEL_DRAG_CAN_START);
   dragState_ = PANEL_DRAG_IN_PROGRESS;
-  [controller_ startDrag];
+  [controller_ startDrag:mouseLocation];
 }
 
 - (void)endDrag:(BOOL)cancelled {
   if (dragState_ == PANEL_DRAG_IN_PROGRESS)
     [controller_ endDrag:cancelled];
   dragState_ = PANEL_DRAG_SUPPRESSED;
 }
 
-- (void)dragWithDeltaX:(int)deltaX
-                deltaY:(int)deltaY {
+- (void)drag:(NSPoint)mouseLocation {
   if (dragState_ != PANEL_DRAG_IN_PROGRESS)
     return;
-  [controller_ dragWithDeltaX:deltaX
-                       deltaY:deltaY];
+  [controller_ drag:mouseLocation];
 }
 
 - (void)drawAttention {
   if (isDrawingAttention_)
     return;
   isDrawingAttention_ = YES;
 
   [self startGlintAnimation];
 }
 
@@ skipping 63 matching lines @@
 }
 
 - (NSTextField*)title {
   return title_;
 }
 
 - (void)simulateCloseButtonClick {
   [[closeButton_ cell] performClick:closeButton_];
 }
 
-- (void)pressLeftMouseButtonTitlebar {
-  NSEvent* event = MakeMouseEvent(NSLeftMouseDown, NSZeroPoint, 0);
+- (void)pressLeftMouseButtonTitlebar:(NSPoint)mouseLocation {
+  NSEvent* event = MakeMouseEvent(NSLeftMouseDown,
+      [self convertPoint:mouseLocation fromView:nil], 0);
   [self mouseDown:event];
 }
 
 - (void)releaseLeftMouseButtonTitlebar {
   NSEvent* event = MakeMouseEvent(NSLeftMouseUp, NSZeroPoint, 1);
   [self mouseUp:event];
 }
 
-- (void)dragTitlebarDeltaX:(double)delta_x
-                    deltaY:(double)delta_y {
+- (void)dragTitlebar:(NSPoint)mouseLocation {
   if (dragState_ == PANEL_DRAG_CAN_START)
-    [self startDrag];
-  [self dragWithDeltaX:delta_x
-                deltaY:delta_y];
+    [self startDrag:dragStartLocation_];
+  [self drag:mouseLocation];
 }
 
 - (void)cancelDragTitlebar {
   [self endDrag:YES];
 }
 
 - (void)finishDragTitlebar {
   [self endDrag:NO];
 }
 
 - (void)updateSettingsButtonVisibility:(BOOL)mouseOverWindow {
   // The settings button is visible if the panel is main window or the mouse is
   // over it.
   BOOL shouldShowSettingsButton =
       mouseOverWindow || [[self window] isMainWindow];
   [[settingsButtonWrapper_ animator]
       setAlphaValue:shouldShowSettingsButton ? 1.0 : 0.0];
 }
 
 - (void)checkMouseAndUpdateSettingsButtonVisibility {
   BOOL mouseOverWindow = NSPointInRect([NSEvent mouseLocation],
                                        [[self window] frame]);
   [self updateSettingsButtonVisibility:mouseOverWindow];
 }
 
 @end