Windows docking should get triggered by pressing against the screen edge

ash/wm/dock/docked_window_layout_manager.h

 // Copyright (c) 2013 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.
 
 #ifndef ASH_WM_DOCK_DOCKED_WINDOW_LAYOUT_MANAGER_H_
 #define ASH_WM_DOCK_DOCKED_WINDOW_LAYOUT_MANAGER_H_
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_layout_manager_observer.h"
 #include "ash/shell_observer.h"
 #include "ash/wm/dock/dock_types.h"
 #include "ash/wm/property_util.h"
+#include "ash/wm/workspace/snap_types.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "ui/aura/client/activation_change_observer.h"
 #include "ui/aura/layout_manager.h"
 #include "ui/aura/window_observer.h"
 #include "ui/gfx/rect.h"
 #include "ui/keyboard/keyboard_controller_observer.h"
@@ skipping 31 matching lines @@
 // TODO(varkha): extend BaseLayoutManager instead of LayoutManager to inherit
 // common functionality.
 class ASH_EXPORT DockedWindowLayoutManager
     : public aura::LayoutManager,
       public ash::ShellObserver,
       public aura::WindowObserver,
       public aura::client::ActivationChangeObserver,
       public keyboard::KeyboardControllerObserver,
       public ash::ShelfLayoutManagerObserver {
  public:
+  // Maximum width of the docked windows area.
+  static const int kMaxDockWidth;
+
   explicit DockedWindowLayoutManager(aura::Window* dock_container);
   virtual ~DockedWindowLayoutManager();
 
   // Disconnects observers before container windows get destroyed.
   void Shutdown();
 
   // Management of the observer list.
   virtual void AddObserver(DockedWindowLayoutManagerObserver* observer);
   virtual void RemoveObserver(DockedWindowLayoutManagerObserver* observer);
 
@@ skipping 13 matching lines @@
 
   ash::Launcher* launcher() { return launcher_; }
   void SetLauncher(ash::Launcher* launcher);
 
   // Calculates if a window is touching the screen edges and returns edge.
   DockedAlignment GetAlignmentOfWindow(const aura::Window* window) const;
 
   // Used to snap docked windows to the side of screen during drag.
   DockedAlignment CalculateAlignment() const;
 
+  // Returns true when a window can be docked. Windows cannot be docked at the
+  // edge used by the launcher shelf or the edge opposite from existing dock.
+  bool CanDockWindow(aura::Window* window, SnapType edge);
+
   aura::Window* dock_container() const { return dock_container_; }
 
   // Returns current bounding rectangle of docked windows area.
   const gfx::Rect& docked_bounds() const { return docked_bounds_; }
 
   // Returns last known coordinates of |dragged_window_| after Relayout.
   const gfx::Rect dragged_bounds() const { return dragged_bounds_;}
 
+  // Returns true if currently dragged window is docked at the screen edge.
+  bool is_dragged_window_docked() const { return is_dragged_window_docked_; }
+
   // aura::LayoutManager:
   virtual void OnWindowResized() OVERRIDE;
   virtual void OnWindowAddedToLayout(aura::Window* child) OVERRIDE;
   virtual void OnWillRemoveWindowFromLayout(aura::Window* child) OVERRIDE {}
   virtual void OnWindowRemovedFromLayout(aura::Window* child) OVERRIDE;
   virtual void OnChildWindowVisibilityChanged(aura::Window* child,
                                               bool visibile) OVERRIDE;
   virtual void SetChildBounds(aura::Window* child,
                               const gfx::Rect& requested_bounds) OVERRIDE;
 
@@ skipping 19 matching lines @@
 
  private:
   FRIEND_TEST_ALL_PREFIXES(DockedWindowResizerTest, AttachTwoWindowsDetachOne);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowResizerTest, AttachWindowMaximizeOther);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowResizerTest, AttachOneTestSticky);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowResizerTest, ResizeTwoWindows);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowResizerTest, DragToShelf);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowLayoutManagerTest, AutoPlacingLeft);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowLayoutManagerTest, AutoPlacingRight);
   FRIEND_TEST_ALL_PREFIXES(DockedWindowLayoutManagerTest,
-                           AutoPlacingLeftSecondScreen);
-  FRIEND_TEST_ALL_PREFIXES(DockedWindowLayoutManagerTest,
                            AutoPlacingRightSecondScreen);
   friend class DockedWindowLayoutManagerTest;
   friend class DockedWindowResizerTest;
 
   // Minimum width of the docked windows area.
   static const int kMinDockWidth;
 
-  // Maximum width of the docked windows area.
-  static const int kMaxDockWidth;
-
   // Width of the gap between the docked windows and a workspace.
   static const int kMinDockGap;
 
   // Minimize / restore window and relayout.
   void MinimizeWindow(aura::Window* window);
   void RestoreWindow(aura::Window* window);
 
   // Updates docked layout state when a window gets inside the dock.
   void OnWindowDocked(aura::Window* window);
 
@@ skipping 66 matching lines @@
   // Observers of dock bounds changes.
   ObserverList<DockedWindowLayoutManagerObserver> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(DockedWindowLayoutManager);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_WM_DOCK_DOCKED_WINDOW_LAYOUT_MANAGER_H_