| // Copyright (c) 2012 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 "ash/wm/window_cycle_controller.h" |
| |
| #include <algorithm> |
| |
| #include "ash/session_state_delegate.h" |
| #include "ash/shell.h" |
| #include "ash/shell_window_ids.h" |
| #include "ash/wm/mru_window_tracker.h" |
| #include "ash/wm/window_cycle_list.h" |
| #include "ash/wm/window_util.h" |
| #include "ash/wm/workspace_controller.h" |
| #include "ui/aura/root_window.h" |
| #include "ui/base/events/event.h" |
| #include "ui/base/events/event_handler.h" |
| |
| namespace ash { |
| |
| namespace { |
| |
| // Filter to watch for the termination of a keyboard gesture to cycle through |
| // multiple windows. |
| class WindowCycleEventFilter : public ui::EventHandler { |
| public: |
| WindowCycleEventFilter(); |
| virtual ~WindowCycleEventFilter(); |
| |
| // Overridden from ui::EventHandler: |
| virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE; |
| private: |
| DISALLOW_COPY_AND_ASSIGN(WindowCycleEventFilter); |
| }; |
| |
| // Watch for all keyboard events by filtering the root window. |
| WindowCycleEventFilter::WindowCycleEventFilter() { |
| } |
| |
| WindowCycleEventFilter::~WindowCycleEventFilter() { |
| } |
| |
| void WindowCycleEventFilter::OnKeyEvent(ui::KeyEvent* event) { |
| // Views uses VKEY_MENU for both left and right Alt keys. |
| if (event->key_code() == ui::VKEY_MENU && |
| event->type() == ui::ET_KEY_RELEASED) { |
| Shell::GetInstance()->window_cycle_controller()->AltKeyReleased(); |
| // Warning: |this| will be deleted from here on. |
| } |
| } |
| |
| } // namespace |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // WindowCycleController, public: |
| |
| WindowCycleController::WindowCycleController() { |
| } |
| |
| WindowCycleController::~WindowCycleController() { |
| StopCycling(); |
| } |
| |
| // static |
| bool WindowCycleController::CanCycle() { |
| // Don't allow window cycling if the screen is locked or a modal dialog is |
| // open. |
| return !Shell::GetInstance()->session_state_delegate()->IsScreenLocked() && |
| !Shell::GetInstance()->IsSystemModalWindowOpen(); |
| } |
| |
| void WindowCycleController::HandleCycleWindow(Direction direction, |
| bool is_alt_down) { |
| if (!CanCycle()) |
| return; |
| |
| if (is_alt_down) { |
| if (!IsCycling()) { |
| // This is the start of an alt-tab cycle through multiple windows, so |
| // listen for the alt key being released to stop cycling. |
| StartCycling(); |
| Step(direction); |
| InstallEventFilter(); |
| } else { |
| // We're in the middle of an alt-tab cycle, just step forward. |
| Step(direction); |
| } |
| } else { |
| // This is a simple, single-step window cycle. |
| StartCycling(); |
| Step(direction); |
| StopCycling(); |
| } |
| } |
| |
| void WindowCycleController::HandleLinearCycleWindow() { |
| if (!CanCycle() || IsCycling()) |
| return; |
| |
| // Use the reversed list of windows to prevent a 2-cycle of the most recent |
| // windows occurring. |
| WindowCycleList cycle_list(MruWindowTracker::BuildWindowList(true)); |
| cycle_list.Step(WindowCycleList::FORWARD); |
| } |
| |
| void WindowCycleController::AltKeyReleased() { |
| StopCycling(); |
| } |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // WindowCycleController, private: |
| |
| void WindowCycleController::StartCycling() { |
| windows_.reset(new WindowCycleList(ash::Shell::GetInstance()-> |
| mru_window_tracker()->BuildMruWindowList())); |
| } |
| |
| void WindowCycleController::Step(Direction direction) { |
| DCHECK(windows_.get()); |
| windows_->Step(direction == FORWARD ? WindowCycleList::FORWARD : |
| WindowCycleList::BACKWARD); |
| } |
| |
| void WindowCycleController::StopCycling() { |
| windows_.reset(); |
| // Remove our key event filter. |
| if (event_handler_) { |
| Shell::GetInstance()->RemovePreTargetHandler(event_handler_.get()); |
| event_handler_.reset(); |
| } |
| } |
| |
| void WindowCycleController::InstallEventFilter() { |
| event_handler_.reset(new WindowCycleEventFilter()); |
| Shell::GetInstance()->AddPreTargetHandler(event_handler_.get()); |
| } |
| |
| } // namespace ash |