blob: 6c9ae9f03b428de7d91bcbb0bb17aea9c8cc6c26 [file] [log] [blame]
// 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.
#include <memory>
#include <vector>
#include "ash/ash_export.h"
#include "ash/wm/window_cycle_controller.h"
#include "base/macros.h"
#include "base/scoped_observer.h"
#include "base/timer/timer.h"
#include "ui/aura/window_observer.h"
#include "ui/display/display_observer.h"
namespace aura {
class Window;
namespace display {
class Screen;
namespace views {
class Widget;
namespace ash {
class WindowCycleView;
// Tracks a set of Windows that can be stepped through. This class is used by
// the WindowCycleController.
class ASH_EXPORT WindowCycleList : public aura::WindowObserver,
public display::DisplayObserver {
using WindowList = std::vector<aura::Window*>;
explicit WindowCycleList(const WindowList& windows);
~WindowCycleList() override;
bool empty() const { return windows_.empty(); }
// Cycles to the next or previous window based on |direction|.
void Step(WindowCycleController::Direction direction);
int current_index() const { return current_index_; }
void set_user_did_accept(bool user_did_accept) {
user_did_accept_ = user_did_accept;
friend class WindowCycleControllerTest;
static void DisableInitialDelayForTesting();
const views::Widget* widget() const { return cycle_ui_widget_; }
const WindowList& windows() const { return windows_; }
// aura::WindowObserver overrides:
// There is a chance a window is destroyed, for example by JS code. We need to
// take care of that even if it is not intended for the user to close a window
// while window cycling.
void OnWindowDestroying(aura::Window* window) override;
// display::DisplayObserver overrides:
void OnDisplayMetricsChanged(const display::Display& display,
uint32_t changed_metrics) override;
// Returns true if the window list overlay should be shown.
bool ShouldShowUi();
// Initializes and shows |cycle_view_|.
void InitWindowCycleView();
// List of weak pointers to windows to use while cycling with the keyboard.
// List is built when the user initiates the gesture (i.e. hits alt-tab the
// first time) and is emptied when the gesture is complete (i.e. releases the
// alt key).
WindowList windows_;
// Current position in the |windows_|. Can be used to query selection depth,
// i.e., the position of an active window in a global MRU ordering.
int current_index_ = 0;
// True if the user accepted the window switch (as opposed to cancelling or
// interrupting the interaction).
bool user_did_accept_ = false;
// The top level View for the window cycle UI. May be null if the UI is not
// showing.
WindowCycleView* cycle_view_ = nullptr;
// The widget that hosts the window cycle UI.
views::Widget* cycle_ui_widget_ = nullptr;
// The window list will dismiss if the display metrics change.
ScopedObserver<display::Screen, display::DisplayObserver> screen_observer_;
// A timer to delay showing the UI. Quick Alt+Tab should not flash a UI.
base::OneShotTimer show_ui_timer_;
} // namespace ash