Added arrow key navigation to Overview Mode

ash/wm/overview/window_grid.h

Index: ash/wm/overview/window_grid.h
diff --git a/ash/wm/overview/window_grid.h b/ash/wm/overview/window_grid.h
new file mode 100644
index 0000000000000000000000000000000000000000..d507a26e68d41bd48faa2d187caf87c0bfd624f0
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+++ b/ash/wm/overview/window_grid.h
@@ -0,0 +1,92 @@
+// Copyright 2014 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_OVERVIEW_WINDOW_GRID_H_
+#define ASH_WM_OVERVIEW_WINDOW_GRID_H_
+
+#include <vector>
+
+#include "ash/wm/overview/window_selector.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace aura {
+class Window;
+}
+
+namespace views {
+class Widget;
+}
+
+namespace ash {

[flackr, 2014/05/29 20:04:25]

nit: blank line after non-trivial namespace block opening.

[Nina, 2014/06/02 22:04:38]

Done.

+class WindowSelectorItem;
+
+// Represents a grid of windows in the Overview Mode in a particular root
+// window.
+class WindowGrid {
+ public:
+  WindowGrid(aura::Window* root_window,
+             std::vector<WindowSelectorItem*> window_list);
+  ~WindowGrid();
+
+  // Creates the selection widget, animating it to the specified |direction|.
+  void CreateSelectionWidget(WindowSelector::Direction direction);
+
+  // Moves the selection widget to the specified |direction|. Returns true if,
+  // after moving, the widget is out of bounds.
+  bool Move(WindowSelector::Direction direction);
+
+  // Positions all the windows in the grid.
+  void PositionWindows(bool animate);
+
+  // Removes |window| from the grid, if present. If this action removes a
+  // WindowSelectorItem, return it. Otherwise, return NULL.
+  // RemoveWindow() repositions the items in the grid if necessary.
+  WindowSelectorItem* RemoveWindow(aura::Window* window);
+
+  // Returns the target selected window, or NULL if there is none selected.
+  WindowSelectorItem* SelectedWindow() const;
+
+  // Returns true if the grid no more windows.

[flackr, 2014/05/29 20:04:25]

nit: s/grid no more/grid has no more

[Nina, 2014/06/02 22:04:38]

Done.

+  bool empty() { return window_list_.empty(); }

[flackr, 2014/05/29 20:04:25]

nit: const.

[Nina, 2014/06/02 22:04:38]

Done.

+
+  // Returns true if the selection widget is active.
+  bool is_selecting() { return selection_widget_ != NULL; }

[flackr, 2014/05/29 20:04:25]

nit: const.

[Nina, 2014/06/02 22:04:38]

Done.

+
+  // Returns the root window in which the grid displays the windows.
+  const aura::Window* root_window() { return root_window_; }

[flackr, 2014/05/29 20:04:25]

nit: const.

[Nina, 2014/06/02 22:04:38]

Done.

+
+ private:
+  // Internal function to initialize the selection widget.
+  void InitSelectionWidget(WindowSelector::Direction direction);
+
+  // Updates |selected_index_| according to the specified |direction|. Returns
+  // |true| if the new selection index is out of this window grid bounds.
+  bool MoveSelectedIndex(WindowSelector::Direction direction);
+
+  // Returns the target bounds of the currently selected item.
+  const gfx::Rect GetSelectionBounds() const;
+
+  // Root window the grid is in.
+  aura::Window* root_window_;
+
+  // Vector containing all the windows in this grid.
+  std::vector<WindowSelectorItem*> window_list_;
+
+  // Widget that indicates to the user which is the selected window.
+  scoped_ptr<views::Widget> selection_widget_;
+
+  // Current selected window position.
+  size_t selected_index_;
+
+  // Grid size.
+  size_t num_rows_;

[flackr, 2014/05/29 20:04:25]

Remove this from the class, it's only used once outside of PositionWindows and
can be easily calculated from num_columns.

[Nina, 2014/06/02 22:04:38]

Done.

+  size_t num_columns_;
+
+  DISALLOW_COPY_AND_ASSIGN(WindowGrid);
+};
+
+}  // namespace ash
+
+#endif  // ASH_WM_OVERVIEW_WINDOW_GRID_H_