Implement cursor compositing mode on Ash

ui/views/corewm/cursor_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 UI_VIEWS_COREWM_CURSOR_MANAGER_H_
 #define UI_VIEWS_COREWM_CURSOR_MANAGER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 43 matching lines @@
   virtual bool IsMouseEventsEnabled() const OVERRIDE;
   virtual void SetDisplay(const gfx::Display& display) OVERRIDE;
   virtual void LockCursor() OVERRIDE;
   virtual void UnlockCursor() OVERRIDE;
   virtual bool IsCursorLocked() const OVERRIDE;
   virtual void AddObserver(
       aura::client::CursorClientObserver* observer) OVERRIDE;
   virtual void RemoveObserver(
       aura::client::CursorClientObserver* observer) OVERRIDE;
 
+  // Toggles native cursor enabled/disabled.
+  // The native cursor is enabled by default.
+  // When disabled, native cursor is hidden even when cursor is visible.

[sky, 2014/02/06 01:33:21]

Doesn't HideCursor/ShowCursor do this? Why do we need this instead of that?

[hshi1, 2014/02/06 01:41:19]

This is intended to hide the native cursor at a lower level (X11) so that it
doesn't interfere with Ash cursor compositing. Otherwise the X11 cursor will be
drawn on top of the Ash desktop and occlude the composited cursor. We can't
simply call HideCursor() here because it will also cause Ash to hide the
composited cursor.

Ultimately I just need the call to arrive in
AshNativeCursorManager::SetNativeCursorEnabled, and this is rather cumbersome to
make several hoops. However I don't know if ash Shell can directly access the
AshNativeCursorManager.

+  void SetNativeCursorEnabled(bool enabled);
+
  private:
   // Overridden from NativeCursorManagerDelegate:
   virtual void CommitCursor(gfx::NativeCursor cursor) OVERRIDE;
   virtual void CommitVisibility(bool visible) OVERRIDE;
   virtual void CommitScale(float scale) OVERRIDE;
   virtual void CommitCursorSet(ui::CursorSetType cursor_set) OVERRIDE;
   virtual void CommitMouseEventsEnabled(bool enabled) OVERRIDE;
 
   scoped_ptr<NativeCursorManager> delegate_;
 
   // Number of times LockCursor() has been invoked without a corresponding
   // UnlockCursor().
   int cursor_lock_count_;
 
   // The current state of the cursor.
   scoped_ptr<internal::CursorState> current_state_;
 
   // The cursor state to restore when the cursor is unlocked.
   scoped_ptr<internal::CursorState> state_on_unlock_;
 
   ObserverList<aura::client::CursorClientObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(CursorManager);
 };
 
 }  // namespace corewm
 }  // namespace views
 
 #endif  // UI_VIEWS_COREWM_CURSOR_MANAGER_H_