ash/accelerators/magnifier_key_scroller.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ash/accelerators/magnifier_key_scroller.h"
   6
   7 #include "ash/accelerators/key_hold_detector.h"
   8 #include "ash/ash_switches.h"
   9 #include "ash/magnifier/magnification_controller.h"
  10 #include "ash/shell.h"
  11 #include "base/command_line.h"
  12
  13 namespace ash {
  14 namespace {
  15 bool magnifier_key_scroller_enabled = false;
  16 }
  17
  18 // static
  19 bool MagnifierKeyScroller::IsEnabled() {
  20   bool has_switch = false;
  21 #if defined(OS_CHROMEOS)
  22   has_switch = base::CommandLine::ForCurrentProcess()->HasSwitch(
  23       switches::kAshEnableMagnifierKeyScroller);
  24 #endif
  25
  26   return (magnifier_key_scroller_enabled || has_switch) &&
  27       ash::Shell::GetInstance()->magnification_controller()->IsEnabled();
  28 }
  29
  30 // static
  31 void MagnifierKeyScroller::SetEnabled(bool enabled) {
  32   magnifier_key_scroller_enabled = enabled;
  33 }
  34
  35 // static
  36 scoped_ptr<ui::EventHandler> MagnifierKeyScroller::CreateHandler() {
  37   scoped_ptr<KeyHoldDetector::Delegate> delegate(new MagnifierKeyScroller());
  38   return scoped_ptr<ui::EventHandler>(new KeyHoldDetector(delegate.Pass()));
  39 }
  40
  41 bool MagnifierKeyScroller::ShouldProcessEvent(const ui::KeyEvent* event) const {
  42   return IsEnabled() &&
  43       (event->key_code() == ui::VKEY_UP ||
  44        event->key_code() == ui::VKEY_DOWN ||
  45        event->key_code() == ui::VKEY_LEFT ||
  46        event->key_code() == ui::VKEY_RIGHT);
  47 }
  48
  49 bool MagnifierKeyScroller::IsStartEvent(const ui::KeyEvent* event) const {
  50   return event->type() == ui::ET_KEY_PRESSED &&
  51       event->flags() & ui::EF_SHIFT_DOWN;
  52 }
  53
  54 void MagnifierKeyScroller::OnKeyHold(const ui::KeyEvent* event) {
  55   MagnificationController* controller =
  56       Shell::GetInstance()->magnification_controller();
  57   switch (event->key_code()) {
  58     case ui::VKEY_UP:
  59       controller->SetScrollDirection(MagnificationController::SCROLL_UP);
  60       break;
  61     case ui::VKEY_DOWN:
  62       controller->SetScrollDirection(MagnificationController::SCROLL_DOWN);
  63       break;
  64     case ui::VKEY_LEFT:
  65       controller->SetScrollDirection(MagnificationController::SCROLL_LEFT);
  66       break;
  67     case ui::VKEY_RIGHT:
  68       controller->SetScrollDirection(MagnificationController::SCROLL_RIGHT);
  69       break;
  70     default:
  71       NOTREACHED() << "Unknown keyboard_code:" << event->key_code();
  72   }
  73 }
  74
  75 void MagnifierKeyScroller::OnKeyUnhold(const ui::KeyEvent* event) {
  76   MagnificationController* controller =
  77       Shell::GetInstance()->magnification_controller();
  78   controller->SetScrollDirection(MagnificationController::SCROLL_NONE);
  79 }
  80
  81 MagnifierKeyScroller::MagnifierKeyScroller() {}
  82
  83 MagnifierKeyScroller::~MagnifierKeyScroller() {}
  84
  85 }  // namespace ash