Corner Passthrough for Accessibility

ui/chromeos/touch_exploration_controller.h

Index: ui/chromeos/touch_exploration_controller.h
diff --git a/ui/chromeos/touch_exploration_controller.h b/ui/chromeos/touch_exploration_controller.h
index 12f0bfa2fcebe0e32d1289d5343f9a0d1dfb0552..2cc4fc856af0d8d9ce8cc4445c17334dcbd01461 100644
--- a/ui/chromeos/touch_exploration_controller.h
+++ b/ui/chromeos/touch_exploration_controller.h
@@ -39,6 +39,11 @@ class TouchExplorationControllerDelegate {
   // Takes an int from 0.0 to 100.0 that indicates the percent the volume
   // should be set to.
   virtual void SetOutputLevel(int volume) = 0;
+
+  // This function should be called whenever the delegate should play an earcon.

[dmazzoni, 2014/07/28 05:32:44]

Update this comment; now the function is just for one specific earcon.

[lisayin, 2014/07/28 16:28:54]

Done.

+  // In the future a parameter can be passed to indicate what sound should be
+  // played.
+  virtual void PlayCornerPassthroughEarcon() = 0;
 };
 
 // TouchExplorationController is used in tandem with "Spoken Feedback" to
@@ -56,7 +61,9 @@ class TouchExplorationControllerDelegate {
 // right would correspond to the keyboard short cut shift+search+right.
 // When two or more fingers are pressed initially, from then on the events
 // are passed through, but with the initial finger removed - so if you swipe
-// down with two fingers, the running app will see a one-finger swipe. Slide
+// down with two fingers, the running app will see a one-finger swipe. If the
+// user holds down the corner of the screen until an earcon sounds, all
+// subsequent fingers will also be passed through in a similar manner. Slide
 // gestures performed on the edge of the screen can change settings
 // continuously. For example, sliding a finger along the right side of the
 // screen will change the volume.
@@ -165,6 +172,8 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
       const ui::TouchEvent& event, scoped_ptr<ui::Event>* rewritten_event);
   ui::EventRewriteStatus InTwoToOneFinger(
       const ui::TouchEvent& event, scoped_ptr<ui::Event>* rewritten_event);
+  ui::EventRewriteStatus InCornerPassthrough(
+      const ui::TouchEvent& event, scoped_ptr<ui::Event>* rewritten_event);
   ui::EventRewriteStatus InPassthrough(
       const ui::TouchEvent& event, scoped_ptr<ui::Event>* rewritten_event);
   ui::EventRewriteStatus InGestureInProgress(
@@ -176,12 +185,21 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
   ui::EventRewriteStatus InSlideGesture(
       const ui::TouchEvent& event, scoped_ptr<ui::Event>* rewritten_event);
 
-  // This timer is started every time we get the first press event, and
-  // it fires after the double-click timeout elapses (300 ms by default).
+  // This timer is started every time we get the first press event and the
+  // finger is not in the corner of the screen.
+  // It fires after the double-click timeout elapses (300 ms by default).
   // If the user taps and releases within 300 ms and doesn't press again,
-  // we treat that as a single mouse move (touch exploration) event.
+  // we treat that as a single mouse move (touch exploration) event. If the user
+  // completes a swipe gesture within 300 ms, then the gesture is processed.
   void OnTapTimerFired();
 
+  // This timer is started every timer we get the first press event and the
+  // finger is in the corner of the screen.
+  // It fires after the long_press timeout elapses (500 ms by default). If the
+  // user is still in the corner by the time this timre fires, all subsequent
+  // fingers added on the screen will be passed through.
+  void OnLongPressTimerFired();
+
   // Dispatch a new event outside of the event rewriting flow.
   void DispatchEvent(ui::Event* event);
 
@@ -285,6 +303,11 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
     // happens until all fingers are up.
     TWO_TO_ONE_FINGER,
 
+    // If the user has pressed and held down the left corner past long press,
+    // then as long as they are holding the corner, all subsequent fingers
+    // registered will be in passthrough.
+    CORNER_PASSTHROUGH,
+
     // If the user is in TWO_TO_ONE_FINGER with two fingers down and presses
     // a third finger, every finger and touch event is passed through until
     // all fingers are released.
@@ -309,6 +332,8 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
     TOP_EDGE = 1 << 1,
     LEFT_EDGE = 1 << 2,
     BOTTOM_EDGE = 1 << 3,
+    BOTTOM_LEFT_CORNER = LEFT_EDGE | BOTTOM_EDGE,
+    BOTTOM_RIGHT_CORNER = RIGHT_EDGE | BOTTOM_EDGE,
   };
 
   // Given a point, if it is within the given bounds of an edge, returns the
@@ -355,7 +380,10 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
   // the location and id of the touch release is from here.
   scoped_ptr<ui::TouchEvent> last_two_to_one_;
 
-  // A timer to fire the mouse move event after the double-tap delay.
+  // A timer that fires after a long press delay.
+  base::OneShotTimer<TouchExplorationController> long_press_timer_;
+
+  // A timer that fires after a double tap delay.
   base::OneShotTimer<TouchExplorationController> tap_timer_;
 
   // A timer to fire an indicating sound when sliding to change volume.
@@ -381,6 +409,10 @@ class UI_CHROMEOS_EXPORT TouchExplorationController
   // This toggles whether VLOGS are turned on or not.
   bool VLOG_on_;
 
+  // Indicates if a finger is in the lower left corner waiting for the timer to
+  // run out.
+  bool waiting_for_corner_passthrough_;
+
   DISALLOW_COPY_AND_ASSIGN(TouchExplorationController);
 };