Moves common code in ash/wm/overview to ash/common/wm/overview

ash/wm/overview/window_grid.h

-// 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 <stddef.h>
-
-#include <memory>
-#include <set>
-#include <vector>
-
-#include "ash/common/wm_window_observer.h"
-#include "ash/wm/overview/window_selector.h"
-#include "base/macros.h"
-#include "base/memory/scoped_vector.h"
-
-namespace views {
-class Widget;
-}
-
-namespace ash {
-
-class WindowSelectorItem;
-
-// Represents a grid of windows in the Overview Mode in a particular root
-// window, and manages a selection widget that can be moved with the arrow keys.
-// The idea behind the movement strategy is that it should be possible to access
-// any window pressing a given arrow key repeatedly.
-// +-------+  +-------+  +-------+
-// |   0   |  |   1   |  |   2   |
-// +-------+  +-------+  +-------+
-// +-------+  +-------+  +-------+
-// |   3   |  |   4   |  |   5   |
-// +-------+  +-------+  +-------+
-// +-------+
-// |   6   |
-// +-------+
-// Example sequences:
-//  - Going right to left
-//    0, 1, 2, 3, 4, 5, 6
-//  - Going "top" to "bottom"
-//    0, 3, 6, 1, 4, 2, 5
-// The selector is switched to the next window grid (if available) or wrapped if
-// it reaches the end of its movement sequence.
-class ASH_EXPORT WindowGrid : public WmWindowObserver {
- public:
-  WindowGrid(WmWindow* root_window,
-             const std::vector<WmWindow*>& window_list,
-             WindowSelector* window_selector);
-  ~WindowGrid() override;
-
-  // Prepares the windows in this grid for overview. This will restore all
-  // minimized windows and ensure they are visible.
-  void PrepareForOverview();
-
-  // Positions all the windows in rows of equal height scaling each window to
-  // fit that height.
-  // Layout is done in 2 stages maintaining fixed MRU ordering.
-  // 1. Optimal height is determined. In this stage |height| is bisected to find
-  //    maximum height which still allows all the windows to fit.
-  // 2. Row widths are balanced. In this stage the available width is reduced
-  //    until some windows are no longer fitting or until the difference between
-  //    the narrowest and the widest rows starts growing.
-  // Overall this achieves the goals of maximum size for previews (or maximum
-  // row height which is equivalent assuming fixed height), balanced rows and
-  // minimal wasted space.
-  // Optionally animates the windows to their targets when |animate| is true.
-  void PositionWindowsMD(bool animate);
-
-  // Positions all the windows in the grid.
-  // Optionally animates the windows to their targets when |animate| is true.
-  void PositionWindows(bool animate);
-
-  // Updates |selected_index_| according to the specified |direction| and calls
-  // MoveSelectionWidget(). Returns |true| if the new selection index is out of
-  // this window grid bounds.
-  bool Move(WindowSelector::Direction direction, bool animate);
-
-  // Returns the target selected window, or NULL if there is none selected.
-  WindowSelectorItem* SelectedWindow() const;
-
-  // Returns true if a window is contained in any of the WindowSelectorItems
-  // this grid owns.
-  bool Contains(const WmWindow* window) const;
-
-  // Dims the items whose titles do not contain |pattern| and prevents their
-  // selection. The pattern has its accents removed and is converted to
-  // lowercase in a l10n sensitive context.
-  // If |pattern| is empty, no item is dimmed.
-  void FilterItems(const base::string16& pattern);
-
-  // Returns true if the grid has no more windows.
-  bool empty() const { return window_list_.empty(); }
-
-  // Returns how many window selector items are in the grid.
-  size_t size() const { return window_list_.size(); }
-
-  // Returns true if the selection widget is active.
-  bool is_selecting() const { return selection_widget_ != nullptr; }
-
-  // Returns the root window in which the grid displays the windows.
-  const WmWindow* root_window() const { return root_window_; }
-
-  const std::vector<WindowSelectorItem*>& window_list() const {
-    return window_list_.get();
-  }
-
-  // WmWindowObserver:
-  void OnWindowDestroying(WmWindow* window) override;
-  // TODO(flackr): Handle window bounds changed in WindowSelectorItem.
-  void OnWindowBoundsChanged(WmWindow* window,
-                             const gfx::Rect& old_bounds,
-                             const gfx::Rect& new_bounds) override;
-
- private:
-  friend class WindowSelectorTest;
-
-  // Initializes the screen shield widget.
-  void InitShieldWidget();
-
-  // Internal function to initialize the selection widget.
-  void InitSelectionWidget(WindowSelector::Direction direction);
-
-  // Moves the selection widget to the specified |direction|.
-  void MoveSelectionWidget(WindowSelector::Direction direction,
-                           bool recreate_selection_widget,
-                           bool out_of_bounds,
-                           bool animate);
-
-  // Moves the selection widget to the targeted window.
-  void MoveSelectionWidgetToTarget(bool animate);
-
-  // Attempts to fit all |rects| inside |bounds|. The method ensures that
-  // the |rects| vector has appropriate size and populates it with the values
-  // placing Rects next to each other left-to-right in rows of equal |height|.
-  // While fitting |rects| several metrics are collected that can be used by the
-  // caller. |max_bottom| specifies the bottom that the rects are extending to.
-  // |min_right| and |max_right| report the right bound of the narrowest and the
-  // widest rows respectively. In-values of the |max_bottom|, |min_right| and
-  // |max_right| parameters are ignored and their values are always initialized
-  // inside this method. Returns true on success and false otherwise.
-  bool FitWindowRectsInBounds(const gfx::Rect& bounds,
-                              int height,
-                              std::vector<gfx::Rect>* rects,
-                              int* max_bottom,
-                              int* min_right,
-                              int* max_right);
-
-  // Returns the target bounds of the currently selected item.
-  const gfx::Rect GetSelectionBounds() const;
-
-  // Root window the grid is in.
-  WmWindow* root_window_;
-
-  // Pointer to the window selector that spawned this grid.
-  WindowSelector* window_selector_;
-
-  // Vector containing all the windows in this grid.
-  ScopedVector<WindowSelectorItem> window_list_;
-
-  // Vector containing the observed windows.
-  std::set<WmWindow*> observed_windows_;
-
-  // Widget that darkens the screen background.
-  std::unique_ptr<views::Widget> shield_widget_;
-
-  // Widget that indicates to the user which is the selected window.
-  std::unique_ptr<views::Widget> selection_widget_;
-
-  // Current selected window position.
-  size_t selected_index_;
-
-  // Number of columns in the grid.
-  size_t num_columns_;
-
-  DISALLOW_COPY_AND_ASSIGN(WindowGrid);
-};
-
-}  // namespace ash
-
-#endif  // ASH_WM_OVERVIEW_WINDOW_GRID_H_