Adding functions to the window_list_provider for accessing the activities window list

athena/wm/public/window_list_provider.h

Index: athena/wm/public/window_list_provider.h
diff --git a/athena/wm/public/window_list_provider.h b/athena/wm/public/window_list_provider.h
index d22aa3da376069285b1c1bf0b1a9f556a3f2fb3d..5ba56ed5f41f936bcfd7ff0fe5ed307b4be57437 100644
--- a/athena/wm/public/window_list_provider.h
+++ b/athena/wm/public/window_list_provider.h
@@ -11,12 +11,41 @@
 namespace athena {
 
 // Interface for an ordered list of aura::Window objects.
+// Note that lists returned by GetCurrentWindowList() will not change if any of
+// the other member functions will be called later.
 class ATHENA_EXPORT WindowListProvider {
  public:
   virtual ~WindowListProvider() {}
 
-  // Returns an ordered list of windows.
-  virtual aura::Window::Windows GetWindowList() const = 0;
+  // Returns an ordered list of the current window configuration.
+  virtual aura::Window::Windows GetCurrentWindowList() const = 0;

[oshima, 2014/09/05 23:13:06]

Current implies there is something else. What's the motivation to use "Current"?

[Mr4D (OOO till 08-26), 2014/09/08 17:35:07]

The returned list will not change if the content changes. As such the list will
be an incorrect representation once it did change. I used "Current" to show that
this is capturing the "current" state - but in the future it might be incorrect.

[oshima, 2014/09/09 18:28:37]

That's same with any API that returns list (aura::Window::children(),
shell::GetAllWindows() etc). I still think current is overkill.

[Mr4D (OOO till 08-26), 2014/09/10 00:01:58]

Done.

+
+  // Returns true if the |window| is part of the list.
+  virtual bool IsWindowInList(aura::Window* window) const = 0;

[oshima, 2014/09/05 23:13:06]

I feel method name are too long. How about

Contains
{Move/Stack/Place}Window{FrontOf/BehindTo}?

[Mr4D (OOO till 08-26), 2014/09/08 17:35:07]

Done.

+
+  // Returns true if the given window is a window which can be handled by the
+  // WindowListProvider.
+  virtual bool IsValidWindow(aura::Window* window) const = 0;
+
+  // Adds a |window| to the front of the list. If the |window| is already in the
+  // list it will be moved to the front.
+  virtual void AddWindow(aura::Window* window) = 0;

[oshima, 2014/09/05 23:13:06]

Do you need this? A window must be added by Widget/WindowTreeClient.

[Mr4D (OOO till 08-26), 2014/09/08 17:35:07]

Someone must have the knowledge of where to add an activity, and for the sake of
knowledge encapsulation (what this is about) this knowledge should reside in one
place. Only this way we get a clear separation of the way how it is managed.

We might want to add this later back in again, but for the time being I have
changed it to observe window changes.

[oshima, 2014/09/09 18:28:37]

Adding is implicit now, so having AddWindow is confusing. I agree that we may
need this when we redesign the list management. We can add it when we need it.

[Mr4D (OOO till 08-26), 2014/09/10 00:01:58]

Acknowledged.

+
+  // Moves a given |window| to the front of all windows of the window list.
+  // Note: The window has to be in the list already.
+  virtual void MoveToFront(aura::Window* window) = 0;
+
+  // Moves a given |window| in direct front of a |reference_window|.
+  // Note: The |window| and |reference_window| has to be in the list already.
+  virtual void MoveWindowInFrontOfReferenceWindow(
+      aura::Window* window,
+      aura::Window* reference_window) = 0;
+
+  // Moves a given |window| directly behind a |reference_window|.
+  // Note: The |window| and |reference_window| has to be in the list already.
+  virtual void MoveWindowBehindOfReferenceWindow(
+      aura::Window* window,
+      aura::Window* reference_window) = 0;
 };
 
 }  // namespace athena