Make touch accessibility gestures work with ChromeVox Next

ui/chromeos/touch_exploration_controller.cc

 // 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 "ui/chromeos/touch_exploration_controller.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/time/default_tick_clock.h"
+#include "ui/accessibility/ax_enums.h"
 #include "ui/aura/client/cursor_client.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/events/event.h"
 #include "ui/events/event_processor.h"
 #include "ui/events/event_utils.h"
 #include "ui/gfx/geometry/rect.h"
 
 #define SET_STATE(state) SetState(state, __func__)
 #define VLOG_EVENT(event) if (VLOG_IS_ON(0)) VlogEvent(event, __func__)
 
 namespace ui {
 
 namespace {
 
 // Delay between adjustment sounds.
 const int kSoundDelayInMS = 150;
 
-// In ChromeOS, VKEY_LWIN is synonymous for the search key.
-const ui::KeyboardCode kChromeOSSearchKey = ui::VKEY_LWIN;
-
 }  // namespace
 
 TouchExplorationController::TouchExplorationController(
     aura::Window* root_window,
     TouchExplorationControllerDelegate* delegate)
     : root_window_(root_window),
       delegate_(delegate),
       state_(NO_FINGERS_DOWN),
       gesture_provider_(new GestureProviderAura(this, this)),
       prev_state_(NO_FINGERS_DOWN),
       VLOG_on_(true),
       tick_clock_(NULL) {
   DCHECK(root_window);
   root_window->GetHost()->GetEventSource()->AddEventRewriter(this);
-  InitializeSwipeGestureMaps();
 }
 
 TouchExplorationController::~TouchExplorationController() {
   root_window_->GetHost()->GetEventSource()->RemoveEventRewriter(this);
 }
 
 ui::EventRewriteStatus TouchExplorationController::RewriteEvent(
     const ui::Event& event,
     std::unique_ptr<ui::Event>* rewritten_event) {
   if (!event.IsTouchEvent()) {
@@ skipping 55 matching lines @@
     if (it == current_touch_ids_.end())
       return ui::EVENT_REWRITE_CONTINUE;
 
     touch_locations_[*it] = location;
   } else {
     NOTREACHED() << "Unexpected event type received: " << event.name();
     return ui::EVENT_REWRITE_CONTINUE;
   }
   VLOG_EVENT(touch_event);
 
+  /**

[David Tseng, 2016/05/05 22:30:39]

nit: remove

[dmazzoni, 2016/05/06 19:06:09]

Done.

   // In order to avoid accidentally double tapping when moving off the edge
   // of the screen, the state will be rewritten to NoFingersDown.
   if ((type == ui::ET_TOUCH_RELEASED || type == ui::ET_TOUCH_CANCELLED) &&
       FindEdgesWithinBounds(touch_event.location(), kLeavingScreenEdge) !=
           NO_EDGE) {
     if (VLOG_on_)
       VLOG(0) << "Leaving screen";
 
     // Indicates to the user that they are leaving the screen.
     delegate_->PlayExitScreenEarcon();
 
     if (current_touch_ids_.size() == 0) {
       SET_STATE(NO_FINGERS_DOWN);
       if (VLOG_on_) {
         VLOG(0) << "Reset to no fingers in Rewrite event because the touch  "
                    "release or cancel was on the edge of the screen.";
       }
       return ui::EVENT_REWRITE_DISCARD;
     }
   }
+  **/

[David Tseng, 2016/05/05 22:30:39]

nit: remove?

[dmazzoni, 2016/05/06 19:06:09]

Done.

 
   // If the user is in a gesture state, or if there is a possiblity that the
   // user will enter it in the future, we send the event to the gesture
   // provider so it can keep track of the state of the fingers. When the user
   // leaves one of these states, SET_STATE will set the gesture provider to
   // NULL.
   if (gesture_provider_.get()) {
     ui::TouchEvent mutable_touch_event = touch_event;
     if (gesture_provider_->OnTouchEvent(&mutable_touch_event)) {
       gesture_provider_->OnTouchEventAck(mutable_touch_event.unique_event_id(),
@@ skipping 634 matching lines @@
 
 // This is an override for a function that is only called for timer-based events
 // like long press. Events that are created synchronously as a result of
 // certain touch events are added to the vector accessible via
 // GetAndResetPendingGestures(). We only care about swipes (which are created
 // synchronously), so we ignore this callback.
 void TouchExplorationController::OnGestureEvent(ui::GestureConsumer* consumer,
                                                 ui::GestureEvent* gesture) {}
 
 void TouchExplorationController::ProcessGestureEvents() {
+  LOG(ERROR) << "ProcessGestureEvents";

[David Tseng, 2016/05/05 22:30:39]

nit: remove

[dmazzoni, 2016/05/06 19:06:09]

Done.

   std::unique_ptr<ScopedVector<ui::GestureEvent>> gestures(
       gesture_provider_->GetAndResetPendingGestures());
   if (gestures) {
     for (ScopedVector<GestureEvent>::iterator i = gestures->begin();
          i != gestures->end();
          ++i) {
       if ((*i)->type() == ui::ET_GESTURE_SWIPE &&
           state_ == GESTURE_IN_PROGRESS) {
         OnSwipeEvent(*i);
         // The tap timer to leave gesture state is ended, and we now wait for
@@ skipping 58 matching lines @@
 void TouchExplorationController::OnSwipeEvent(ui::GestureEvent* swipe_gesture) {
   // A swipe gesture contains details for the direction in which the swipe
   // occurred. TODO(evy) : Research which swipe results users most want and
   // remap these swipes to the best events. Hopefully in the near future
   // there will also be a menu for users to pick custom mappings.
   GestureEventDetails event_details = swipe_gesture->details();
   int num_fingers = event_details.touch_points();
   if (VLOG_on_)
     VLOG(0) << "\nSwipe with " << num_fingers << " fingers.";
 
-  if (num_fingers > 4)
-    return;
+  ui::AXGesture gesture = ui::AX_GESTURE_NONE;
+  if (event_details.swipe_left()) {
+    switch (num_fingers) {
+      case 1: gesture = ui::AX_GESTURE_SWIPE_LEFT_1; break;
+      case 2: gesture = ui::AX_GESTURE_SWIPE_LEFT_2; break;
+      case 3: gesture = ui::AX_GESTURE_SWIPE_LEFT_3; break;
+      case 4: gesture = ui::AX_GESTURE_SWIPE_LEFT_4; break;
+      default: break;
+    }
+  } else if (event_details.swipe_up()) {
+    switch (num_fingers) {
+      case 1: gesture = ui::AX_GESTURE_SWIPE_UP_1; break;
+      case 2: gesture = ui::AX_GESTURE_SWIPE_UP_2; break;
+      case 3: gesture = ui::AX_GESTURE_SWIPE_UP_3; break;
+      case 4: gesture = ui::AX_GESTURE_SWIPE_UP_4; break;
+      default: break;
+    }
+  } else if (event_details.swipe_right()) {
+    switch (num_fingers) {
+      case 1: gesture = ui::AX_GESTURE_SWIPE_RIGHT_1; break;
+      case 2: gesture = ui::AX_GESTURE_SWIPE_RIGHT_2; break;
+      case 3: gesture = ui::AX_GESTURE_SWIPE_RIGHT_3; break;
+      case 4: gesture = ui::AX_GESTURE_SWIPE_RIGHT_4; break;
+      default: break;
+    }
+  } else if (event_details.swipe_down()) {
+    switch (num_fingers) {
+      case 1: gesture = ui::AX_GESTURE_SWIPE_DOWN_1; break;
+      case 2: gesture = ui::AX_GESTURE_SWIPE_DOWN_2; break;
+      case 3: gesture = ui::AX_GESTURE_SWIPE_DOWN_3; break;
+      case 4: gesture = ui::AX_GESTURE_SWIPE_DOWN_4; break;
+      default: break;
+    }
+  }
 
-  if (event_details.swipe_left() &&
-      !left_swipe_gestures_[num_fingers].is_null()) {
-    left_swipe_gestures_[num_fingers].Run();
-  } else if (event_details.swipe_right() &&
-             !right_swipe_gestures_[num_fingers].is_null()) {
-    right_swipe_gestures_[num_fingers].Run();
-  } else if (event_details.swipe_up() &&
-             !up_swipe_gestures_[num_fingers].is_null()) {
-    up_swipe_gestures_[num_fingers].Run();
-  } else if (event_details.swipe_down() &&
-             !down_swipe_gestures_[num_fingers].is_null()) {
-    down_swipe_gestures_[num_fingers].Run();
-  }
+  if (gesture != ui::AX_GESTURE_NONE)
+    delegate_->HandleAccessibilityGesture(gesture);
 }
 
 int TouchExplorationController::FindEdgesWithinBounds(gfx::Point point,
                                                       float bounds) {
   // Since GetBoundsInScreen is in DIPs but point is not, then point needs to be
   // converted.
   root_window_->GetHost()->ConvertPointFromNativeScreen(&point);
   gfx::Rect window = root_window_->GetBoundsInScreen();
 
   float left_edge_limit = window.x() + bounds;
@@ skipping 10 matching lines @@
     result |= LEFT_EDGE;
   if (point.x() > right_edge_limit)
     result |= RIGHT_EDGE;
   if (point.y() < top_edge_limit)
     result |= TOP_EDGE;
   if (point.y() > bottom_edge_limit)
     result |= BOTTOM_EDGE;
   return result;
 }
 
-void TouchExplorationController::DispatchShiftSearchKeyEvent(
-    const ui::KeyboardCode third_key) {
-  // In order to activate the shortcut shift+search+<arrow key>
-  // three KeyPressed events must be dispatched in succession along
-  // with three KeyReleased events.
-
-  ui::KeyEvent shift_down(
-      ui::ET_KEY_PRESSED, ui::VKEY_SHIFT, ui::EF_SHIFT_DOWN);
-  ui::KeyEvent search_down(
-      ui::ET_KEY_PRESSED, kChromeOSSearchKey, ui::EF_SHIFT_DOWN);
-  ui::KeyEvent third_key_down(ui::ET_KEY_PRESSED, third_key, ui::EF_SHIFT_DOWN);
-
-  ui::KeyEvent third_key_up(ui::ET_KEY_RELEASED, third_key, ui::EF_SHIFT_DOWN);
-  ui::KeyEvent search_up(
-      ui::ET_KEY_RELEASED, kChromeOSSearchKey, ui::EF_SHIFT_DOWN);
-  ui ::KeyEvent shift_up(ui::ET_KEY_RELEASED, ui::VKEY_SHIFT, ui::EF_NONE);
-
-  DispatchEvent(&shift_down);
-  DispatchEvent(&search_down);
-  DispatchEvent(&third_key_down);
-  DispatchEvent(&third_key_up);
-  DispatchEvent(&search_up);
-  DispatchEvent(&shift_up);
-}
-
-base::Closure TouchExplorationController::BindShiftSearchKeyEvent(
-    const ui::KeyboardCode third_key) {
-  return base::Bind(&TouchExplorationController::DispatchShiftSearchKeyEvent,
-                    base::Unretained(this),
-                    third_key);
-}
-
 void TouchExplorationController::DispatchKeyWithFlags(
     const ui::KeyboardCode key,
     int flags) {
   ui::KeyEvent key_down(ui::ET_KEY_PRESSED, key, flags);
   ui::KeyEvent key_up(ui::ET_KEY_RELEASED, key, flags);
   DispatchEvent(&key_down);
   DispatchEvent(&key_up);
   if (VLOG_on_) {
     VLOG(0) << "\nKey down: key code : " << key_down.key_code()
             << ", flags: " << key_down.flags()
@@ skipping 151 matching lines @@
     case ONE_FINGER_PASSTHROUGH:
       return "ONE_FINGER_PASSTHROUGH";
     case WAIT_FOR_NO_FINGERS:
       return "WAIT_FOR_NO_FINGERS";
     case TWO_FINGER_TAP:
       return "TWO_FINGER_TAP";
   }
   return "Not a state";
 }
 
-// TODO(evy, lisayin) : Just call abstracted methods on the delegate (e.g.
-// Swipe(Direction direction, int num_fingers)), and add the DispatchXYZ
-// methods to the delegate. Avoid the middle step of dispatching keys at all,
-// and simply have ChromeVox/ChromeOS complete the required action.
-
-void TouchExplorationController::InitializeSwipeGestureMaps() {
-  // Gestures with one finger are used for navigation.
-  left_swipe_gestures_[1] = BindShiftSearchKeyEvent(ui::VKEY_LEFT);
-  right_swipe_gestures_[1] = BindShiftSearchKeyEvent(ui::VKEY_RIGHT);
-  up_swipe_gestures_[1] = BindShiftSearchKeyEvent(ui::VKEY_UP);
-  down_swipe_gestures_[1] = BindShiftSearchKeyEvent(ui::VKEY_DOWN);
-
-  // Gestures with two fingers.
-  left_swipe_gestures_[2] =
-      BindKeyEventWithFlags(ui::VKEY_BROWSER_BACK, ui::EF_NONE);
-  right_swipe_gestures_[2] =
-      BindKeyEventWithFlags(ui::VKEY_BROWSER_FORWARD, ui::EF_NONE);
-  // Jump to top.
-  up_swipe_gestures_[2] = BindShiftSearchKeyEvent(ui::VKEY_A);
-  // Read from here.
-  down_swipe_gestures_[2] = BindShiftSearchKeyEvent(ui::VKEY_R);
-
-  // Gestures with three fingers switch tabs left/right and scroll up/down.
-  left_swipe_gestures_[3] = BindKeyEventWithFlags(
-      ui::VKEY_TAB, ui::EF_CONTROL_DOWN | ui::EF_SHIFT_DOWN);
-  right_swipe_gestures_[3] =
-      BindKeyEventWithFlags(ui::VKEY_TAB, ui::EF_CONTROL_DOWN);
-  up_swipe_gestures_[3] = BindKeyEventWithFlags(ui::VKEY_NEXT, ui::EF_NONE);
-  down_swipe_gestures_[3] = BindKeyEventWithFlags(ui::VKEY_PRIOR, ui::EF_NONE);
-
-  // Gestures with four fingers should probably eventually be used for rare
-  // needs that are hard to access through menus.
-  // Note that brightness levels are here because they can be important for low
-  // vision users. However, none of these mappings are permanent.
-  left_swipe_gestures_[4] =
-      BindKeyEventWithFlags(ui::VKEY_BRIGHTNESS_DOWN, ui::EF_NONE);
-  right_swipe_gestures_[4] =
-      BindKeyEventWithFlags(VKEY_BRIGHTNESS_UP, ui::EF_NONE);
-  up_swipe_gestures_[4] = BindKeyEventWithFlags(VKEY_BROWSER_HOME, ui::EF_NONE);
-  down_swipe_gestures_[4] =
-      BindKeyEventWithFlags(VKEY_BROWSER_REFRESH, ui::EF_NONE);
-}
-
 float TouchExplorationController::GetSplitTapTouchSlop() {
   return gesture_detector_config_.touch_slop * 3;
 }
 
 }  // namespace ui